Foundations of Amateur Radio (Onno (VK6FLAB))

A little while ago I had the chance to use a mobile radio with high power. I used it to learn about the coverage of our local repeater, but also to hear what the effects were when two local radios were both using the same repeater and high power at the same time.

I made all manner of observations and wondered how much of what I observed was real and how much was a case of me adding two and two together and coming up with five. Immediately after I made those observations I received emails from around the globe explaining in great detail what was going on.

Suffice to say that there was some disagreement among the emails, but overall they lead to a few new things that I'd not considered.

One comment was that the two radios, not quite side-by-side, but in two cars nearby was similar to the operating environment of a repeater, that is a receiver and a transmitter sitting in close proximity. Initially I didn't cotton on to the analogy and it took several readings to understand, but the outcome is that, as I suspected, the receiver is being overloaded by a local transmitter which is putting out a big signal that is overwhelming the electronics in the receiver, something that a repeater deals with every time you key it up. The short version of this is called de-sensing. I'm still reading about how it exactly works on the inside, something for another day.

In a repeater the issue is dealt with by filtering the outgoing signal and filtering the incoming signal, making sure that only the desired information makes it to where it needs to go. Two random radios bolted to two cars don't have any such filtering and no way to reject the unwanted signals. Adding filters to both cars might fix the issue, but then we weren't trying to fix anything, just to learn what was going on.

Another thing I learnt was that FM receivers don't need an AGC, since the volume of a signal is related to how much it deviates from the central signal, not how much signal there is, which is why the microphone gain setting on your radio determines the volume, not the level of power. To be clear, enough of your signal needs to get to the other end for it to work, but after that, you're just wasting electrons. If you need a visual for that in FM the height of the signal doesn't matter once it's high enough, the wobble determines how much volume there is. In AM, there is no wobble, the height determines the volume.

Incidentally, if not enough of your signal gets to the other end, then your weak signal might be overtaken by another signal and the so-called "FM capture effect" happens, where the low signal gets effectively rejected in favour of the higher one.

Interestingly Amateur Radios can have an FM AGC which can be used to determine the signal strength, which makes your S-meter behave more like it does on HF, but if you recall, an S-meter is really a guess-o-meter since every manufacturer has their own "standard" and two radios are unlikely to experience the same S-level for the same signal. Don't misunderstand, I'm not maligning the S-meter, just pointing out that your S-5 and my S-5 are unlikely to be the same.

So, the more I peel away from my little mobile experiment, the more I unearth in the wake of the experiment. Such is the joy of Amateur Radio. Be curious, investigate and learn.

I'm Onno VK6FLAB

Get on air and make some noise is a phrase I use often to encourage amateurs to be active on-air and use the bands that are available to us.

One thing that's often glossed over is how to actually make that noise. It can be scary to make that first contact.

If you've got your radio installed, your antenna erected, your operating position set-up just right and you're ready to actually key your microphone, how do you do that and how do you get the attention of those around you?

First things first.

You need to establish if your radio is actually working as expected. If you're using a UHF or VHF radio, often the simplest way is to find a local repeater, key-up your radio and give your callsign. The result should be at least a carrier, a beep or a callsign in Morse-code. Some repeaters even have a voice ident, so you can hear that your action of keying the push-to-talk had an effect. If that isn't working, then there are lots of things you can troubleshoot, but that's for another day.

If you want to do the same on HF, unless you happen to be in a position that there is a repeater within propagation distance, generally only on the 6m and 10m bands, then you're essentially out of luck. There isn't a beep, or a carrier, or a voice-ident to be found. This means we have to solve the problem in a different way.

First of all, if you cannot hear any stations, the chances of someone hearing you are slim. So, the first thing to do is to check that the squelch on your radio is set to allow all signals to arrive at your speaker. Then find a band where it's noisy. When I say noisy, find one where there is lots of hiss. Generally speaking an open band, one where propagation is getting a signal to you, makes noise, lots of noise. There are exceptions to this, but for now, find the noise.

Depending on how you have your antenna set-up, you need to make sure that you're using the right antenna for the band you're using. Some antennas work on multiple bands, others only on one, it depends entirely on what you have got hanging off the end of your radio.

Once you've found the noisiest band, go hunting for beeps, as-in Morse-code beeps, or voices, or digital sounds. Find a signal, find evidence of activity. If you have multiple noisy bands, check them all.

You might recall that this is all dependent on the ionosphere, so depending on what's going on with the sun, things will change, sometimes within a minute, an hour, or weeks. Generally there is a difference between day and night and sunrise and sunset, so experiment.

Once you've found some activity, you need to find someone to talk to. If the voice you hear is weak, look for a strong one. The stronger the better. While this isn't universally true, it's a good starting experience. Every radio and antenna combination has a sweet spot on where you know that they can hear you, but you don't know yet what that sweet spot is, so trial and error is the way to go.

HF is not like the local repeater. The people on HF can be anywhere on the planet. They might be there for the first time, or for the third time that day having been on air for sixty years, it's hard to tell.

A good analogy is to think of a sport stadium with a hundred thousand people in it. There are people all around you and you're trying to make contact with one of them. You can pick their frequency, but they're likely to be talking to someone else. You might be interrupting a daily chat, a regular net, or happen upon a contest or a special event station. You don't know which one it is and sometimes you can't hear both sides of the conversation. So, before you key your microphone and make some noise, listen to what is going on.

Once you've figured out that the station you're hearing might be amenable to talking, wait for a break in the conversation, key your microphone and just say your callsign phonetically, once. If there's no break, that's a good indication that the other station doesn't want to talk to you, unless there is an endless stream of stations, in which case the going might be tough and you might be there for a while.

If the other station acknowledges your call, great, you just made contact. Confirm that you have their callsign and that they have yours, write it down with the time and frequency, then start with exchanging information, start with a signal report. In the beginning, less is more. Your first name and city is often more than enough.

All we're doing is establishing that we can talk to someone and that they can talk to us. Don't overdo it, get a feeling for what's going on.

Then do it again.

And again.

Before long you'll have some experience on how to get on air and make some noise and you can start learning about improving your skills, becoming familiar with your radio and being an active amateur.

Hopefully that wasn't so scary, and remember, every amateur had to make their first contact one day, even those who have been on-air for longer than you've been alive.

I'm Onno VK6FLAB

Today in Amateur Radio is no different from yesterday, last year, last decade or longer. The hobby today is filled with people who are here to have fun, learn stuff and experiment. This hasn't changed since our hobby came into being.

You can argue that the hobby has seen a great many changes. We have seen spark-gap transmitters, valves, transistors, miniaturisation, chips and now software defined radios. The experimental nature of our pursuit has not changed.

We still spend time looking for cool stuff to do and people to do it with.

And that's the single point I'd like to make.

Finding people "to do it with".

If you're a new amateur you might look to a club or your fellow classmates to combine your efforts. This can be a great way to forge life-long friendships and it's a sure fire way to find exposure to other ideas and activities.

There might come a time when you find yourself at a loss what to do next, or who to do it with. You might lament that the group you're hanging out with are not doing fun stuff anymore, or that activities never quite happen or any number of observations that make it less fun to be part of amateur radio.

I've now been here for a little while and I've noticed that some of my fellow amateurs have fallen by the way-side. Of course family and changing interests will account for some of that, but often it's a lack of something to do that makes people fade away.

There is nothing stopping you from organising your own event. You can plan a camp-out, or an antenna testing day, or a DX activity, a contest, an activation, some software hacking, or hardware building, soldering training, learning how to log, how to do a QSO, or any number of other things.

If you tell the community about it, you're likely to be surprised by some other amateur who was just thinking to do the same thing.

So, don't wait for someone else to do your fun activity. If you focus on doing things that you enjoy, you might find a few like-minded friends who will participate.

I'm keen to hear your ideas and activities, so drop me a line.

I'm Onno VK6FLAB

If you walk into your radio shack and switch on a light, the result is instantaneous, one moment it's dark, the next it's not. What if I told you that as immediate as it appears, there is actually a small delay between you closing the circuit and the light coming on. Likely the distance between your switch and your light is less than say 10 meters, so the delay is likely to be less than 33 nanoseconds, not something you'd notice unless you're out to measure it.

What if your light switch is 3,200 km away? That's the length of the first transatlantic telegraph cable in 1858.

Let's start with the notion that between the action of closing a switch, or applying a voltage at one end of the cable and it being seen at the other end takes time. If we ignore the wire for a moment, pretending that both ends are separated by vacuum, then the delay between the two ends is just over 10 milliseconds because that's how long it takes travelling at the speed of light. One of the effects of using a cable is that it slows things down. In case you're curious, the so-called Velocity Factor describes by how much. A common Velocity Factor of 66 would slow this down by 66%.

This means that there is a time when there is voltage at one end and no voltage at the other.

There are a few other significant and frequency dependent things going on, we'll get to them, but before we go any further, it's important to consider a couple of related issues.

Ohm's Law, which describes the relationship between voltage, current and resistance in an electrical circuit was first introduced in 1827 by Georg Ohm in his book: "The Galvanic Chain, Mathematically Worked Out". Initially, his work was not well received and his rival, Professor of Physics Georg Friedrich Pohl went so far as to describe it as "an unmistakable failure", convincing the German Minister for Education that "a physicist who professed such heresies was unworthy to teach science."

Although today Ohm's Law is part and parcel of being an amateur, it wasn't until 1841 that the Royal Society in London recognised the significance of his discovery, awarding the Society's oldest and most prestigious award, the Copley Medal, in recognition for "researches into the laws of electric currents".

I'll point out that Ohm only received recognition because his work was changing the way people were starting to build electrical engines and word of mouth eventually pressured the Royal Society into the formal recognition he deserved.

I also mentioned the speed of light in relation to the delay between applying a voltage and it being seen at the other end, but it wasn't until 1862 when James Clerk Maxwell published a series of papers called "On Physical Lines of Force" that light speed was actually derived when he combined electricity and magnetism and proved that light was an electromagnetic wave, and that there were other "invisible" waves, which Heinrich Rudolph Hertz discovered as radio waves in 1888.

How we understand transmission lines today went through a similar discovery process. Your radio is typically connected to an antenna using a length of coaxial cable, which is a description for the shape the cable has, but the nature of the cable, what it does, is what's known as a transmission line.

If you looked at the submarine telegraph cable of 1858, you'd recognise it as coaxial cable, but at the time there wasn't much knowledge about conductance, capacitance, resistance and inductance, let alone frequency dependencies. James Clerk Maxwell's equations weren't fully formed until 1865, seven years after the first transatlantic telegraph cable was commissioned and the telegraph equations didn't exist until 1876, 18 years after the first telegram between the UK and the USA.

In 1854 physicist William Thomson, was asked for his opinion on some experiments by Michael Faraday who had demonstrated that the construction of the transatlantic telegraph cable would limit the rate or bandwidth at which messages could be sent. Today we know William Thomson as the First Lord Kelvin, yes, the one we named the temperature scale after. Mr. Thomson was a prolific scientist from a very young age.

Over a month, using the analogy with the heat transfer theory of Joseph Fourier, Thomson proposed "The Law of Squares", an initial explanation for why signals sent across undersea cables appeared to be smeared across time, also known as dispersion of the signal, to such an extent that dits and dahs started to overlap, requiring the operator to slow down in order for their message to be readable at the other end and as a result, message speed for the first cable was measured in minutes per word, rather than words per minute.

Today we know this phenomenon as intersymbol interference.

It wasn't until 1876 that Oliver Heaviside discovered how to counter this phenomenon using loading coils based on his description of what we now call the Heaviside condition where you can, at least mathematically, create a telegraph cable without dispersion. It was Heaviside's transmission line model that first demonstrated frequency dependencies and this model can be applied to anything from low frequency power lines, audio frequency telephone lines, and radio frequency transmission lines.

Thomson worked out that, against the general consensus of the day, doubling the line would actually quadruple the delay needed. It turns out that the length of the line was so significant that the second cable laid in 1865, 560 km shorter, outperformed the original cable by almost ten times, even though it was almost identical in construction, providing physical proof of Thomson's work.

It has been said that the 1858 transatlantic telegraph cable was the scientific equivalent of landing man on the Moon. I'm not sure if that adequately explains just how far into the unknown we jumped. Perhaps if we blindfolded Neil Armstrong whilst he was landing the Eagle...

I'm Onno VK6FLAB

Today I'm operating portable, in fact I'm operating portable every day. Though I'd have to confess, some days more than others.

I have to do this by necessity. There is lots of RF noise at home, so I'm forced to physically move away from the interference and set up elsewhere.

You can do this as simply or as complex as you like. I've done it with a bag that contained my radio, a battery and a wire antenna that I strung between two trees.

I've also gone portable with my car, camping gear, a trailer full of radio gear, a wind up mast and a rotatable dipole with a generator to provide power.

And everything in between.

My point is that for every circumstance there is a different set of tools that will solve your problem.

Several amateurs I've spoken to are quite unsure about this portable adventure and are not really geared up for such shenanigans even if they're interested to get out and about.

So what is involved with going portable?

The essence of any station is the antenna. If you know where you're going to operate and why, you can figure out what kind and how much of an antenna you need to bring. Likely a mast and rotator are not part of the deal, but I have set up a yagi on mast in a park for a contest.

If you don't know where you're going to be, you need to come up with a solution that is more flexible. Either a self supporting vertical with something like a squid pole or a wire antenna that you can throw into a tree.

The next challenge is power. Are you going to operate for a little while or are you going to set up for 48 hours to participate in a contest. Are you going to be using low power, 5 watts, or are you in a position where you can give an amplifier a workout?

Batteries, generators, your car or a solar panel, all of these can power your radio in different situations.

Are you planning to make a few contacts, or are you expecting a huge pileup to get your blood pumping? Logging for either requires a different solution.

You should always, always consider the weather when you're operating portable. Sun, wind, rain, storm, hot and cold all have different implications for you personally and the wear and tear of your equipment. So prepare yourself.

Just like when you started your shack, you had to figure out what goes where and how will I use it?

Portable operation is no different.

A tip for new players, less is more. You have to carry all this stuff, so expect to make compromises. You won't be able to take everything in your shack, unless you already built it in the back of your vehicle, in which case I'd like an invite to come and visit.

I'm Onno VK6FLAB

This is episode 236 or so of my weekly contribution to this hobby. As you may have heard me say over the past few weeks, this is now available as a podcast which you can subscribe to. It's available at http://podcasts.itmaze.com.au and you can also search for my callsign, VK6FLAB on iTunes and find it there.

I'm mentioning this because each podcast also contains a transcript, which you can use to search the content. I've been doing this podcast since May 2011 and in that time I've covered many topics.

I get wonderful feedback from you about each segment, thank you, and I also get requests for content. Often new listeners ask me if I could talk about XYZ topic, and I'm finding more and more that in fact I have talked about such a topic.

That's not to say that I won't revisit a topic if I have information to add. For example, I was in the process of researching baluns, got distracted by word-use and will revisit. As I'm doing the research I'm realising that the rabbit hole goes deep on that particular topic, so I'm not yet at a point where I can say much about it other than to think of a balun as a maths tool for feed-point impedance, that is to say, a 6 to 1 balun will transform a 300 Ohm feed-point to a 50 Ohm one, similarly a 9 to 1 will do the same for a 450 Ohm feed-point. All fine and dandy, but why would you need a 1 to 1 balun. Or what's the difference between a voltage balun and a current balun, not to mention the bandwidth, the different material types, and on it goes.

So, I'm not yet at the point where I can distil the information to a three minute segment, but I will.

I've also discussed cows and lightning in the past. If you remember, if a cow is facing the impact point of lightning, they can die from the current that flows along their body from their front legs to their rear legs. Which is why you want a single point earth in your station.

I hope that you'll take the opportunity to have a look-see across the previous editions of this segment and find something to your liking.

I'm Onno VK6FLAB.

This and previous editions can be found online at http://podcasts.itmaze.com.au/ and are also available for download from iTunes and other podcast directories. Just search for my callsign.

Life is messy. This is not a revelation. We attempt to organise this chaos by using all kinds of magic incantations, to-do lists, new year resolutions, plans, projects and anything else you might have in your arsenal. The same chaos reigns, in how we make progress. Some days are harder than others. I'm mentioning this because I've seen a couple of amateurs share all the things they didn't achieve last year. If we used that metric, I could point out that I didn't win the lotto, likely, neither did you, or your friends. I didn't get on HF to make a contact, I didn't put up a 6BTV antenna, the list is never ending.

In other words, it's easy to say what you didn't do. What if you turned this upside down? I hosted my weekly radio net for its thirteenth year, I had my beacon heard more times than I have bandwidth available to check right now, I started a project that looks like it's going to keep me busy for some time to come. I've been working my way through a full system crash and I can see light out the end of the tunnel, six months later.

So, don't beat yourself up about all the things you didn't do.

Speaking of that, making plans is fine, but don't use the to-do list as a way to describe all the things you didn't do, instead, think of it as an inspiration for what to do when you're bored.

Chaotic aspects of life aside, the same disorder reigns supreme in the software world. GNU Radio on which I'm basing the "Bald Yak" project is just as chaotic. New versions are released regularly. Right now it's at version 3.10.something. On my Mac, it's 3.10.11.0, on my Debian machine it's 3.10.5.1. Depending on which operating system you use it's different, there's a wiki table, but that's out of date, before you ask, yes, I've requested an account on the GNU Radio wiki so I can fix it.

This only scratches the surface of things that are, for want of a better word, disharmonious. This might be perceived as chaos, but the reality is that this exists throughout the computing world. If you're not a software developer you might have only scratched the surface of this, trying to open a document written for a different version of your word processor, installing a new operating system and finding software that was working perfectly before, suddenly doesn't.

GNU Radio is a complex beast. The latest release has 5,570 files, making nearly 80,000 lines of source and related code. The git repository shows 579 authors and I will point out that it's likely there are more, since the project was first released in 2001, but the git repository only goes back to 2006.

Said differently this is a big project that nobody is likely to hold entirely inside their brain. It means that things change without everyone involved knowing about it. I'm raising this because we're diving into a complex environment that we're using to build ourselves a new thing.

At this point you might want to run for the hills. I understand.

One of the great things about society is our ability to abstract. It's why I'm typing on a keyboard with letters of the alphabet and not punching holes into cardboard. It's why I'm looking at a screen with graphics and controlling images with my finger, rather than looking at dozens of blinkenlights that provide a lifetime of memories.

GNU Radio is the abstraction of radio. That's the whole point. It allows us to pick up a signal block, tell it to make a kilohertz tone, connect it to my loudspeaker so sound comes out. It looks simple on the outside, but underlying that is a level of complexity that you will only encounter when it comes to raise its chaotic head.

This all to say that I did make some progress. When you play an audio tape at half speed, or play a single at 33 RPM instead of 45 RPM, the result is that the audio is slower, but it also means that the audio is lower in frequency. It led me to wonder if I can use that phenomenon to help me hear better. What if I could play audio slower and have my ears be able to hear better. Right now, anything above 2 kHz is hard to hear. I keep asking my partner, "Say again?", "Sorry, what?", "Sorry, I didn't hear that."

Hearing aids seem to attempt to deal with the problem by amplifying the sounds you cannot hear. This results in squealing and all manner of other unpleasantness. It also doesn't seem to help me. Instead I wondered if I could halve a 4 kHz tone to 2 kHz, I could hear it. So, if I play audio at half speed, I can hear more. Unfortunately it would also mean that I would be running behind all the time. So, what if I could play at half speed and remove half the audio samples? I can confirm that with simple tones this works and I did this inside GNU Radio with pretty much one block, "Keep M in N samples", in this case, keep one in two. I halved the sample rate and all was well.

Why is this significant?

Well, aside from that it might help me hear better, it represents the first time I had an idea that I could try out in realtime and see what it did. For a bunch of reasons I haven't yet moved on to actually hearing it, by setting the source as the microphone and the sink as my headphones, but that's on the cards soon.

Making progress is a series of chaotic steps that take you on a journey. If you're lucky, the journey will get you where you want to go.

I'm Onno VK6FLAB

One of the regular topics of conversation in amateur radio, especially for those new to the community, is where to start? The sheer volume of available options is often overwhelming. If you've never encountered the complexity associated with this amazing hobby the experience can be disheartening and even demoralising.

In my early years I was results driven. Getting on air, making noise, logging a contact, adding a country, winning a contest, rinse and repeat, get better, do more. There have been numerous occasions when I came home from one of my adventures disappointed, sometimes bitterly so.

That happened for quite some time, until one day I realised that the journey in and of itself is the reward.

That might sound disingenuous, so let me illustrate.

This week I set-up an automatic beacon in my shack that can be heard by stations around the planet, letting me know just how far my signal can travel at any particular moment, using my own station antenna and local propagation. As projects go, it continues to be an adventure.

As you might recall, I like low power operation, truth be told, I love low power. The smaller, the better. Less is more and all that. I recently completed the first leg of a journey to set-up a permanent beacon. For years I'd been dabbling around the edges. On the weekend, whilst I was in my shack, I'd regularly set-up my computer and radio, set it to WSPR beacon and see what stations heard me. I couldn't turn my radio below 5 Watts, so that's what I used. Before you start, yes, I could turn down the volume, but that involves math and I wanted a result, now.

It filled a gap using WSPR, Weak Signal Propagation Reporter, like that. For a while, I improved on things by having a receiver set-up that monitored the bands all day every day and recently I turned it back on, with limited success, more on that shortly.

What I really wanted was to see where my signal was going, not what I could hear. I received a few emails suggesting that a ZachTek WSPR Desktop transmitter, built and sold by Harry, SM7PNV, would be just the ticket. It's a little metal box with USB and SMA connectors. One SMA for the supplied GPS antenna, used for location and time, the other for a transmit antenna. USB provides serial for configuration and power if it's operating in stand-alone mode. Yes, you can operate it without needing a computer and if you want it does band-hopping. After configuring it with things like your callsign and bands, you can plug-in the GPS, your antenna and power it via USB and it will run as an automatic 200 milliwatt WSPR beacon.

That device in turn prompted a journey to discover a more appropriate antenna, since my current station antenna uses an automatic tuner that won't get triggered by this tiny transmitter. That caused an exploration in how and where to mount any new antenna, with a side-trip into finding a specific anti-seize compound locally. To pick the mounting hardware, I had to get into wind loading, how strong my satellite dish mount might be, how to install and tune a multi-band antenna. The list just keeps growing and that voyage continues.

I'm tracking the requirements with a project specific check-list, just to make sure that I don't miss any steps and have a place to document new discoveries when they invariably hit me in the face. So-far, so-good.

The WSPR monitor receiver is currently connected to a generic telescopic dipole, mounted indoors, which in the past gave me a much better result than my station vertical, so I should be able to keep both running.

Next on the list is to construct a live propagation map for my station, then a way to switch modes on that map, so I can tell if it's worth calling CQ without going blue in the face. I'm also working on a WSPR transmitter for 2m and 70cm, because they are under served in my neck of the woods.

The takeaway from all this is that whilst there are many steps, and truth be told, that list is growing as I learn, each step is tiny and doable. The only thing that separates me from someone who doesn't know where to start, is this.

I started. You can too. Anywhere. Doesn't matter. Pick anything that tickles your fancy. Start digging. It's a hobby, not a profession. What ever floats your boat, what ever makes you excited, what ever you're interested in, pick it and do something, anything.

That's how you get anywhere in Amateur Radio, and Open Source, and life for that matter, just start.

I'm Onno VK6FLAB

When you start life you learn early on the difference between being told about an experience and the actual experience. There's a saying that comes to mind, I use it regularly in my day job: In theory there is no difference between theory and practice, while in practice there is.

I thought I'd do the quote justice to see where it came from, not from Einstein, who was three years old at the time it was coined and neither Yogi Berra or Richard Feynman had been born. Quote Investigator puts it in the Yale Literary Magazine of February 1882 and attributes it to Benjamin Brewster, but I digress.

A little while ago the regulator in Australia altered the rules of engagement in relation to amateur radio for people holding the license that I do. All Australian amateurs are now permitted to transmit digital modes. Not that this should have been any impediment to the exploration of the receive side, but I had a few other things on my plate to try. Still do.

Over the weekend I sat in my driveway with my radio and had the urge to see if I could actually do some PSK31, a digital mode that had a low entry barrier, since there were defined frequencies, and I could use a decoder on my phone.

So, I set about doing just that. I had already programmed in the various frequencies into my radio the week before. I hadn't actually heard any signals, but that didn't deter me. I set about getting myself set-up for what I'm calling a driveway hack.

Picture this. A folding table with my radio. A stool next to it with me on it. The radio connected to an antenna, a vertical that was attached to a neighbour's roof with a magnetic mount and my phone running DroidPSK. I was tuned to the 10m PSK frequency, had the volume turned up, holding my phone next to the speaker, watching the waterfall.

Nothing.

I called up a mate who had this all working and we set about trouble shooting my set up.

He made some transmissions; nothing.

I listened to the 10m beacon, loud and clear.

He made some more transmissions, still nothing.

Then we realised while I was switching back and forth between the beacon and the PSK frequency that his radio was set up for a different standard PSK frequency. Gotta love standards, there's one for every occasion. Changed my frequency and for the first time I could actually see stuff in the waterfall display on my phone.

If you've never seen a waterfall display, it's a tool that helps visualise the signal strength of a chunk of spectrum over time. It's pretty nifty and a waterfall displays a lot of information.

Starting with colour, the idea is that a colour represents a particular signal strength. Red for full signal, yellow for half, blue for the lowest detected signal and black for no signal. Fill in the gaps with the colours of the rainbow.

If you represent a line made of dots with the start of the line at say 0 Hz and the end of the line at say 3 kHz, you could split the line into 300 dots, and each dot could be coloured to represent the average signal strength for a little 10 Hz slice of spectrum.

If you wait a second, move the line you drew down and then measure again, you'd end up with two lines. The line from now at the top, the line from a second ago below it. If you do this every second, you'll end up with lines flowing off the bottom of the screen, the oldest lines at the bottom and the newest ones at the top.

That is a waterfall display. Over time you'll start to recognise what a particular signal looks like on the waterfall and there are even modes where you can draw on the waterfall, but I'll leave that for another day.

As I said, I could now finally see signals on my waterfall display.

I'm not going to dig too deep here, because there's much confusion in the language surrounding all this and I intend to get the names straight in my mind before I express them here, but after figuring out that you have to tell DroidPSK which signal you want to decode, I finally managed to decode the transmission from my friend.

After putting on some headphones and realising that the clicks I was hearing from my phone were actually artefacts from the speaker, I also managed to transmit a CQ signal which my friend decoded. He then acknowledged my callsign in his next transmission.

So, I now have two screen shots, his and mine, showing that we both saw each other using 10m PSK31. There wasn't a signal strength exchange, mainly because I have yet to figure out how to determine that and where it's visible, but for all the things that matter, I managed a contact with PSK31 thanks to Randall VK6WR, very exciting!

Since then I've started experimenting with decoding WebSDR, that's HF signals coming in via the internet and being decoded on my computer from the web audio. I'm still working on that, but there is so much to learn and play with and a transmitter isn't yet needed to have fun. I should mention that you can also decode satellite signals like this.

Digital modes, just when you thought that the rabbit hole couldn't get any deeper.

I'm Onno VK6FLAB

The story goes that the name of our hobby, at least in some parts of the world, ham radio, stems from the notion that we as a community were perceived as being ham-fisted in our ability to operate a Morse key. We apparently claimed that slur and made it our own. I've never actually been able to verify this narrative, but it goes to the heart of what it is to be part of the hobby of amateur radio, as opposed to Professional radio, which is what I once heard someone refer to themselves as.

This notion that we are playing outside our sandbox, that we're doing something less than real, that we're somehow not whole as a result is absurd, especially in the context of how we are an integral part of how spectrum is allocated around the globe. It's fun to remember that playing outside the box, trialling things, exploring, inventing and learning, is the reason we're here.

The whole thing is incremental, much like learning to walk, sometimes you fall flat on your face, yet here you are perambulating like a champ. As an aside, did you know that how you get up off the floor is pretty much how you learnt to do it as a toddler, it might not be the most efficient, but it's how you do it. Speaking of falling down, making mistakes on-air is part and parcel of being an amateur. There's no protocol police, nobody to issue a fine if you make a mistake, just dust yourself off and try again.

The urge to optimise pervades our hobby. We optimise our antennas, our gear, the time and band we choose to communicate on, the modes we use, the places we operate from, even how we participate in contests, all of it is a cycle of optimisation.

During contests I've regularly attempted to flex my imagination to optimise my activities. For example, the VK Shires contest rewards you for combinations of shires, so, I created a map of all the shires, then looked for places to activate, preferably on or near borders, so I could change shire with minimal effort. There are contests that reward different maidenhead locators, so I set about finding spots where you could activate four at once. By the way, a maidenhead locator is an amateur radio geo-locator which I'll dig into some other time. Contesters regularly use multiple radios to optimise their ability to talk to stations that double their points, so-called multipliers.

Over the years I've come across many different excuses for getting on-air and making noise. Popular activities like Parks On The Air, or POTA, Summits On The Air or SOTA, and plenty of others are all programs that aim to get you out of your shack, set up your station at a particular location and make contact with anyone and everyone. On occasion you'll hear a station combining activities, doing both a POTA and a SOTA activation because the summit is inside the boundaries of a national park.

Ian M0TRT took this idea to a whole new level. He wondered if you could qualify for multiple programs simultaneously and if so, how many. Gathering data from Summits, Parks, Islands, Beaches and Bunkers on the Air, together with UK Castle and Lighthouse awards and adding World Wide Flora and Fauna or WWFF, eight programs in all, he set about exploring. For some programs like Castles, Lighthouses and Bunkers you need to be within 1 km of the entity and summits need to be activated within 25 meters altitude from the peak. For other programs, beaches, parks and islands plenty of extra work was needed. Ian's code is available on GitHub, in the "weeaaoa" or "Worked Everything Everywhere All At Once Award" repository.

If you have time to head out to the beach just east of Devil's Point near Plymouth you'll be able to activate 21 different programs at the same time. The Maidenhead locator is IO70WI06.

As with any outdoor amateur radio activity, take nothing but pictures, leave nothing but footprints and kill nothing but time. Be mindful of creating obstacles and trip hazards for your fellow humans and be prepared to have a park ranger turn up as soon as you sit down.

Oh, and if you think that's not in the spirit of amateur radio, you haven't been paying attention.

I'm Onno VK6FLAB

Today I was looking around my shack and noticed that I have lots of different amateur radio tools that go beyond the simple bits and pieces that I started with, namely a radio, battery, power supply, coax and antenna.

While I have no illusion that my gear is complete, or even representative of all of the stuff that you might need or come across, I think that it's worth while to mention a few bits and pieces that you may not have considered.

I think the first thing I got that wasn't part of the basic kit, was a dummy load. It's only a little one, rated at 50 Watts or so, but seeing that I'm only using 5, that's more than enough. I use it to check things like VOX sensitivity, that is, I want to set-up a way to talk into my radio without having to push a button - for when I'm doing a contest, and I don't actually want to transmit any signal while testing, so I plug in the dummy load and test with that. I also use it to plug into the end of a piece of coax that I'm testing. I can tell you, it's helped me find some dodgy coax over the years.

I have a range of adaptors, from PL259, SO239, N-type, SMA, BNC, male-to-male, male-to-female, female-to-female, all different permutations. They're all in one box and I have that with me whenever I go portable, it's saved my bacon more times than I can remember.

I have a multi-meter, the most often used part of it is the continuity beep. You can set it to beep if there is a short, which is great for testing power leads, coax shorts and the like.

I splurged and purchased an antenna analyser. It's helping me understand the errors of my ways while building antennas, though I confess that on more than one occasion it added to the confusion.

I have a coax cutter, a pair of high quality pliers, though one of my so called friends left it in the rain one day, so they're less quality than they were, an Anderson Powerpole crimper, a gas soldering iron - so you can solder in the field, a third-hand, since holding something while soldering is an excellent way to get a scar to impress your friends. On my workbench I have a lighted magnifying glass, since the older I get the harder it is to focus on small things. I have a bag of clip-on torroids which I use in places where operating surprises me with bonus RF interference.

I also have stuff like cable-ties, electrical tape, self-amalgamating tape and a fair bit of rope.

You'll notice that I don't have an SWR meter, I figured that the one in my radio and the antenna analyser combined were enough.

I'm sure there are other things that I take for granted, but the items I've outlined are in regular use.

I'm Onno VK6FLAB

There is a persistent perception among a small part of the amateur community that you need to build, buy or use antennas with a perfect 1:1 SWR to get the best results. Sometimes a contest erupts with who can get the lowest SWR.

Without getting technical, since that could take hours and you have better things to do. A 50 Ohm dummy load has a perfect SWR of 1:1 and you should already know that a proper dummy load doesn't radiate, so while it has a perfect SWR it's not a perfect antenna.

If your SWR meter reads 1.5:1, you're losing 3% of your signal, at 2:1 it's 11%, so just because the SWR is 2, doesn't mean you've got a dud antenna.

Now I should point out that this can be a particularly dense topic if you get into the finer detail and if you do a search for "Understanding SWR by Example", you'll come across a delightful and very detailed document written by Darrin K5DVW and published in QST magazine that goes into pictures, graphs and explanations and also discusses ladder line.

So, you can now stop hunting for the perfect 1:1 SWR and learn what your SWR meter is telling you.

I'm Onno VK6FLAB

A recurring question for people who are not yet, or newly licensed is something along the lines of: I have a friend who is 400 kilometres away, can I talk to them on my hand-held 2m radio?

This particular question arrives in different forms, but generally along the lines of attempting to communicate between point A and point B at some or other distance.

The responses, on social media at least, less so on-air, are often very technical, or offer the advice to get a license, or to get a clue, or the question is ignored or dismissed. That's not helpful, or fair. The person asking the question has expressed an interest in our hobby and is looking for help.

As a basic set of answers, if you're both standing on the ground, you'll generally be able to talk about 5km using your hand-held. Stuff between you like buildings and hills will lower that distance. If you both stand on a hill, you can talk further away. As an aside, you can talk to the International Space Station with a 2m, 144 MHz hand-held because there is nothing between you and it when it's overhead, even though it's 350 km away.

If you cannot see between the two, then an intermediate radio, a repeater, can facilitate the connection. It needs to have visibility to both radios at the same time. The higher the middle point, the further the distance. For example an antenna at 350m above the ground has a so-called radio horizon of 77km and I should point out that that's actually 15% further than actual line of sight. As long as both ends are within that radius, you should be pretty much good to go.

You can theoretically string together a whole bunch of repeaters, along a road for example, but more often than not, for distances greater than line of sight you need to invoke radio frequencies that your 2m hand-held won't do. These frequencies are generally referred to as HF and is generally anything between 3 and 30 MHz. Radio transmissions on these frequencies mainly use the ionosphere to make contact possible and you can make contacts from as close as next-door, to as far as the opposite side of the world.

The ionosphere is subject to weather in much the same way as clouds and rain. The variation in the ionosphere is driven by the sun, not by wind and humidity, and it varies throughout the day as the sun rises and sets. Communication varies depending on where the sun is and several other factors well outside this explanation. As the ionosphere changes, usable frequencies change. Something that worked one moment might not the next because the ionosphere changed.

As a licensed radio amateur you have access to many different frequencies and depending on the state of the ionosphere you can change frequency as required to alter your station to suit the conditions. You can think of it as adjusting your sail depending on the wind direction, to get from A to B.

One final point. Antennas are many and varied. They are designed for specific purpose and will react differently depending on how they're designed, built, installed and used, so the variation you're stepping into is enormous.

This hobby is nothing like dialling a phone number and making a connection, it's all about the experience and the learning. If that tickles your fancy, you're already halfway to becoming an amateur. Welcome.

I'm Onno VK6FLAB

Several years ago I participated in a local contest. Over a 24 hour period I activated my mobile station in about 30 different locations. On my car, my vertical antenna screwed into a boot-lip mount connected to an antenna tuner or ATU, and my radio. I used rope to guy the antenna, threaded through the rear windows and held tight by closing the car boot.

Setting up consisted of parking the car, triggering the ATU to tune the antenna system and calling CQ. Moving to the next location consisted of driving there and setting up again.

Although this worked really well, I'm skipping over what I'm interested in exploring today.

The phrase "triggering the ATU to tune the antenna system" hides a lot of complexity. It was a surprise to me that there were several locations where the ATU just wouldn't tune. Despite my best efforts I was unable to get the system to a point where the radio was happy. In some cases I tuned off frequency and put up with a poor SWR. In others I physically had to move the car and park somewhere else.

In every case it was completely unknown if a particular location was going to be a problem. I recall for example parking in an empty nondescript car-park and having to drive around to find a location where my set-up would work. Afterwards I considered that the car-park was potentially built on top of an iron ore deposit, an old industrial area, or a pipe-line, all of which were a good possibility.

The point of this is that an antenna doesn't exist in isolation, it's called a system for a reason. We talk about the theoretical isotropic antenna and add disclaimers about that it cannot physically exist because it's infinitely small. One often overlooked aspect of an isotropic antenna is that it's in free space.

Free space is defined as space that contains no electromagnetic or gravitational fields and used as a reference. It's a theoretical place. On Earth there is no such thing, there's a planet under your feet, but even in outer space there are both gravitational and electromagnetic fields that impact on an antenna and its performance.

Staying nearer to home, recently we had a discussion about how close two antennas can be together. A suggested rule of thumb was that they need to be at least one banana or 30 cm away from each other.

Similarly when we erect a dipole, there's recommendations around needing to have it mounted more than half a wavelength over the ground. Some sources say higher. I'll ask the first obvious question. Is that dipole completely straight? In other words, should the centre be half a wavelength above the ground, or should the ends, and how far should the ends be from their mounts?

My point is that every antenna exists within the context of its environment and together it's a system. Some environments help the performance of your antenna system and some don't. Depending on frequency, this might not be the same for any location, or antenna design.

To be clear, an antenna system consists of the antenna, the feed line and the clips that hold it, the tuner, the radio and its power supply, the mount and the space around it, the radials, the tower, the pigeon poop on the wire, all of it.

Until recently my process to get any antenna to perform in a reasonable manner was to set it up, connect an antenna analyser, scan the appropriate range, tweak the antenna, scan again, rinse and repeat until it arrived at something approaching useful, or until it was good enough.

If you recall, I recently added some loading coils to a telescopic antenna to attempt to make it resonant on 10m, so I could connect my Weak Signal Propagation Reporter or WSPR beacon to it directly and leave it running independently from my main station.

I used the antenna analyser method, got it to the point where I had an antenna with a nice dip right at the required frequency and then watched it go completely sideways when I mounted the antenna in the window.

Having spent several hours getting to that point, I walked away and left it for another day. Today was that day. I again started on the floor of my shack and got nothing but an infinite SWR and no amount of tweaking could fix it. Right until the coax fell out of the SMA connector I was scratching my head.

After removing the faulty coax lead, I again tweaked the antenna and instead of using my antenna analyser, I fired up my NanoVNA, a tiny handheld open-hardware Vector Network Analyser or VNA. If you're not familiar, it's a standalone palm sized device with an LCD display and battery which will allow you to test most of your RF equipment. This little box came to me via a generous gift from a fellow amateur. It can repeatedly scan a range of frequencies and report in near real-time what's going on. Instead of waiting a minute after each adjustment, I could wait less than a second and immediately see the effect.

This has been a game changer.

I could mount the antenna against a metal surface and immediately see what the impact was. I could see the difference between it being mounted horizontally, where it would sag, to it being vertical where it stayed straight. I could see the steepness of the SWR plot, see how the low point moved around, up and down the band, see what the depth or lowest SWR was at any point. I could see my hand approaching the antenna, how nearby metal objects affect the antenna, what made it better and what made it worse.

The reason that I'm talking about this is because it's the very first time that I was able to actually get a feel for what affects an antenna, in what way and by how much.

To describe an analogy, it's like watching someone play a theremin and hearing how their hands affect the sound. If you're not familiar, a theremin is an electronic musical instrument controlled without physical contact by the performer, named after its inventor, Leon Theremin who patented it in 1928. From the outside it looks like a metal antenna that you bring your hands near to change the field. The changes are converted into sound.

The NanoVNA gives you the same level of feedback, but does so visually in a quantitative way, providing you with the insight to adjust your antenna to your liking and taking into account its entire environment.

Does this mean that I'm telling you to go out and buy one today? Well, that's not up to me, but I am intensely grateful for it arriving at my doorstep.

I'm Onno VK6FLAB

One of the first questions a new amateur asks is "Which radio should I buy?" It's a topic I've discussed at length and the answer "It depends." is unhelpful without doing more research, but after you've done the work, you'll be able to answer it for yourself.

A question that is just as important, but not asked nearly enough, frankly, I've not heard it in the decade I've been part of this community, is: "How should I build my shack?" The answer is just as useful, "It depends."

So, let's explore what precisely your shack design depends on. Let me start with pointing out that I'm not here to give you answers, you can watch hundreds of YouTube videos, read a gazillion web-pages and get no closer than discover how others have answered this question. It wasn't until recently that I understood that it was a question at all, but airing my frustration at the level of dysfunction of my shack unearthed it and in attempting to answer my own question, I started to explore the landscape.

As with choosing a first radio, one of the very first answers you need for yourself about the ideal shack is: "What do you want to use it for?"

That in and of itself is not enough. I had an answer for that, I want to operate my weekly net, I want to do casual HF contesting, have a beacon running and have space for experimentation. It wasn't until Ben VK6NCB suggested that I dedicate a single radio to the weekly net and the contesting and use the other for experimentation, that I discovered that this wasn't going to work for me.

I want to be able to use both my radios at the same time, in a so-called Single Operator Two Radio setup, or SO2R. This will allow me to extend the boundaries of my comfort zone and in doing so, will give me plenty of new things to learn.

So, the question: "What do you want to use your shack for?" is probably the single most important thing you need to discover. If you're like me, the obvious answer is: "Everything!", but reality soon sets in and you might start to create an actual list of things that you want to do. Prompted by Ben's suggestion, I was able to articulate for the very first time something that I didn't want to do. I didn't want to set a radio aside for experimentation. So when you're considering what you want to achieve, also think about what you don't want.

For example, I have no interest in using the 6 meter band at this time. Not because it's a bad band, far from it, it's because I'm not permitted to use it with my current license. Same for the 23 cm band. This means that I don't have to find ways of making my shack accommodate those two bands. My current license permits me access to precisely six bands and the station I'm building only needs to access those bands at the moment. That brings me to the next question for the ideal shack design.

"How long do you expect the layout to last?"

For example, are you going to build a new building for your shack, for the next 50 years, or is it something that's going to last for the weekend? Is your shack going to be moved, or is it something a little more permanent? Are you going to change your needs and should you incorporate some of that into your design, or are you perfectly happy with what you're doing today? You have to remember, this is your shack, not mine, not your friends, yours. It means that it needs to accommodate what you want.

The next question, boring as it might be, "How much money are you going to spend?"

Building a whole new shack out of a catalogue is perfectly fine, but you might discover that the gear you have today is ample to get your shack started. You might leave space for a different piece of kit, or you might decide that the shack needs changing when a new shiny piece of equipment arrives in a nondescript brown box.

Some other things to consider are, "What operating actually looks like?"

I've seen shack videos that look like a tour through a radio museum with more radios than I have keys on my keyboard, sometimes all connected, other times, just stored on shelves to look at.

Are you going to have more than one radio operating at the same time and if so, how are you planning to control them? How many antennas are connected to this shack and how do you track which antenna is connected to which radio?

What are you going to do about power? Does everything run on mains power, or are you going to build a 13.8 Volt supply for all your gear?

Where are you planning to put computer screens, what about keyboard, mouse, Morse key and antenna switching controls? In other words, "What do the ergonomics of your shack look like?"

Remember, there is no right answer. The answer you come up with is yours and yours alone. Look at things that work for you and take note of things that make you wince when you see it in another shack somewhere. That's not to say that you should be dismissive, rather, use the opportunity to ask the shack owner why they made that choice. Who knows, it might cover something you hadn't considered yet.

So, what does your ideal shack look like?

I'm Onno VK6FLAB

Antennas and propagation are the two single most discussed topics in our hobby, that and how an FT8 contact isn't real. Not a day goes by without some conversation about what antenna is the best one and by how much? In my opinion it's a futile effort made all the worse by so called experts explaining in undeniable gobbledegook, or sometimes even using science, just how any particular antenna is a compromise.

The truth is that most conductive materials radiate to more or lesser degree. Sometimes there is enough of that to make it outside your backyard into the antenna of a fellow hobbyist. To make a point, as is my wont, over the past months I've been conducting an experiment. It's the first in a series all related to antennas and propagation. As has been said, the difference between fiddling and science, is writing it down, so this is me writing it down.

I'm using the tools available to me to explore the various attributes of my station and how it affects what's possible. I will observe that this is within the dynamic nature of the environment, so the solar cycle, solar events, thunderstorms and noise are making an impact. No doubt I'll create a visualisation that links some of those extra variables, but for now I'm just noting that these external events affect what I'm doing.

You might recall that I took delivery of a WSPR beacon a few months ago. If you're unfamiliar, WSPR or Weak Signal Propagation Reporter, is a tool that allows a station to transmit a time synchronised signal on a specific frequency, so other stations can look for, and attempt to decode it. Think of it as a timed Morse code signal and you'll have a pretty close understanding of what it does.

The beacon I purchased was a 200 milliwatt, ZachTek 80To10 desktop transmitter, built by Harry, SM7PNV. It can operate on all the HF bands I'm licensed for and can run all day, every day. It's time-synchronised using a supplied GPS antenna and powered by a Micro USB cable. It's currently connected to my vertical antenna.

That vertical antenna is a homebrew helically wound whip, tuned for the 40m band, clamped to the side of my metal patio roof. It's fed by an SGC-237 antenna coupler which is held by magnets to the roof. A 75 Ohm, RG6 quad shield coax cable, about 20m long, left over from my satellite dish installation days, is connected via several adaptors and coax switches to the beacon.

This is not a fancy set-up by any stretch of the imagination, but it's my station and what I use to get on air to make noise and that's the whole point of this exercise. You might recall that one of the reasons I want to learn Morse is so I can hear an NCDXF beacon and know which one I'm hearing on my own station. In many ways, this is a different way to approach the same problem.

Said plainly, "How do I determine what propagation is like for me, right now, on my own gear?"

There are countless tools available, from the Voice of America VOACAP propagation prediction, through the graphs and charts on clublog.org to the Space Weather Services run by the Bureau of Meteorology in Australia.

All of these tools have one thing in common, they don't use your own gear.

Unsurprisingly, you're likely to wonder what it is that I can achieve with a mere 200 milliwatt transmitter and a vertical. Turns out, quite a lot. As of right now, my WSPR beacon has been heard multiple times over the past three months in the Canary Islands, over 15 thousand kilometres away. The Watts per Kilometre calculation puts that at over 76 thousand kilometres per Watt, not bad for a little amateur station located in the middle of a residential suburb. Did I mention that this was on the 10m band?

I was asked if I would put a pin in my DXCC map, tracking the countries for each of these WSPR reports and my answer to that is "No". This is not a contact, this is a propagation ping. I suppose that I could, if I really wanted to argue the point, which I don't, use a pin if I had a reciprocal report from the other station within a set period of time, but that's not why I'm doing this. The purpose of this exercise is to discover what my station is capable of, what propagation is like, how it changes over time, how uniform my radiation pattern is and how much of the globe can hear my signal.

One observation to make is that much of the West Coast of the United States is a similar distance away from me, but so far there are no reports from that continent. As a quick and dirty test, I'm using my Yaesu radio and 5 Watts for the next day to see if this is an edge case, or if there is something else going on. For example, my house has a peak metal roof, to the West of my antenna. Is it possible that it's affecting the radiation pattern, or is there something else going on, like the neighbour's house that sits to the East?

For all I know the noise floor in the Canary Islands is significantly better than anywhere in the USA, but only time will tell.

I've recently taken delivery of a multi-band vertical antenna which I'm planning to use to replace my current vertical. The main reason being that my antenna coupler cannot tune with 200 milliwatts and to do band-hopping I'd have to re-tune manually each time, not something that is sustainable 24 hours a day.

No doubt that change will bring other discoveries, but then, I'm keeping track.

The intent of all of this is that you can experiment with your own station, test ideas, trial a set-up, keep a log and discover new things that your station presents to you. Amateur Radio is never just about one thing, it's always a dozen different things, all at the same time.

What are you going to discover next?

I'm Onno VK6FLAB

Recently the Australian Space Weather Forecasting Centre issued an alert for a Coronal Mass Ejection or CME expected to impact Earth within 24 to 36 hours. This was presented within the context of seeing the resulting Aurora, but as a user of the HF radio spectrum, I'm subscribed to their email list, not for the pretty pictures, though I would be delighted to actually see them with my mark one eyeball, I'm on the list for the impact on propagation for my hobby.

As a good citizen I shared the alert with my community both via email and social media and as a result I received some questions and comments. One question was, "What does this mean?", one comment was "it's not going to impact the United States."

My response was to point out that HF propagation and the impact of the Sun is a very deep rabbit hole and encouraged further research by supplying several links, including a very detailed video by Rohde and Schwarz titled "Understanding HF Propagation", very, highly, recommended.

Whilst watching that video I discovered that the Solar Flux Index is measured using a receiver tuned to 2800 MHz or 2.8 GHz. Being in the business of having receivers scattered around my shack, I asked myself if I had something that was able to receive on that frequency. My RTL-SDR dongle doesn't cut it without extra hardware, it tops out at 1.75 GHz. However, my PlutoSDR has a standard frequency range that goes up to 3.8 GHz out - of the box - and with some tweaks can make it to 6 GHz, so well and truly within range.

Now, before I move on, I should mention that an RTL-SDR is a cheap, as-in $20, USB computer accessory that looks like a thumb-drive and is ostensibly built to receive digital television, or DVB-T signals. I've spoken about this previously. It can be used to receive radio frequencies outside the purpose it was built for. The PlutoSDR, or to give its official name the ADALM-PLUTO, on the other hand, something which I've also spoken about, is a single board Linux computer made by some smart people at Analog Devices, specifically for the purposes of learning and experimentation with receiving and transmitting RF. It comes with all manner of documentation and software and to be honest, I'm a little bit in love with mine.

Back to measuring stuff. In this case I'm attempting to measure the power levels of radio frequencies at 2.8 GHz. I know of a simple tool called rtl_power that can measure RF power over time and started investigating if that tool had been hacked to be able to use the PlutoSDR, rather than the RTL-SDR dongle. It might have been, but I've not yet discovered it, however, that in turn led me to several other tools, most of which I'm still investigating.

What it does tell me is that I'm not the first person to tread these paths, much has happened and been documented in the analogue sphere, some has been done using digital I/Q data and a transverter, a device that can multiply radio frequencies to make them appear in a different part of the radio spectrum, but I'm not yet sure if anyone has made a Solar Flux Index device out of a PlutoSDR.

I recalled a wonderful little tool that I've also talked about before, there's a theme here, I'm sure, but the tool, "csdr", written by Andras HA7ILM, which allows you to do all manner of interesting things to a stream of raw data, specifically RF raw data. It has a function called logpower_cf which Andras describes as "useful for drawing power spectrum graphs", which is precisely what I'm looking for.

Armed with that I'm now in the process of building a compiled version using Docker, so I can run csdr on my PlutoSDR and perhaps generate a power spectrum graph for 2.8 GHz. Of course that will now require that I learn how to extract raw data, known as I/Q data from the PlutoSDR command-line, process it through the logpower_cf function, output an image and hopefully show the result as a web-page. At the moment I'm still in the weeds with a Makefile, but that's not unusual.

Needless to say that I'm working on it and the result will no doubt turn up on my github page when it's done. In the most innocent terms possible, how hard can it be?

One takeaway that really needs to be expressed out loud, even if I've hinted at it. All the bits I've talked about here are things I've already been playing with. It wasn't until I came across a salient piece of information about the Solar Flux Index and how it was measured that all the puzzle pieces came together, the PlutoSDR, csdr, rtl-power, logpower_cf, the SFI and a web-server, that I could even imagine this happening.

The point being that even if you have all of the puzzle pieces in your hands, it might still take one missing piece of information for your brain to go "Ah-ha, wow, yes, this makes sense, I can do this."

So, keep collecting puzzle pieces, relevant to your own interests and one day you too will get to this point.

I'm Onno VK6FLAB

Recently I talked about making a propagation map in your mind by listening to the various NCDXF beacons across the globe on various HF bands. You're not limited to listening to a beacon to learn what propagation is like.

If I tell you that listening to a band gives you an indication on what's going on, you're likely to respond with: "Duh".

But what if I suggest that instead of listening to a DX station running a pile-up, you instead listen to the stations calling?

Back in January 2014, episode 133, when this series was still called "What use is an F-call?", I explained what "Listening 10-up" means and how you operate in a so-called split mode. As you might recall, working split is about dealing with the phenomenon that a weak DX station working in some desirable location is likely to be overwhelmed by stronger signals, to the point of no longer being heard. It's a good skill to learn and you should try and work both sides, being the station calling a DX, but also being the one getting swamped.

As I said, normally you're the one calling the DX station and you don't particularly care about the other stations swamping the band.

What if you did?

What if you used their signals to figure out where propagation was happening? If you did that, you could perhaps point your antenna in the correct direction, or specifically focus on calling for stations in that area, or listen out for stations in that region in other parts of the band.

The thing is, propagation doesn't care what the signal is. As long as you can decode it in what ever way you prefer, Mark I ear-drum, or some fancy decoder, it doesn't matter. If you can hear the signal, it means it's getting from them to you.

I should note a word of caution here.

It's taken me several years to realise that I could often hear many stations that had no chance of hearing me. I'd crank up the volume on the radio, listen out for anything and try to work what I heard. Sometimes you get a great result, and you shouldn't discount those, but often all I got for my trouble is a sore head from decoding mush.

What I learned, especially as a low power operator - I use 5 Watts - if the other station isn't coming in with a reasonable signal strength, S5 or higher, then there's little point.

There is a concept of reciprocity. The idea is that if you can hear them, you can work them. For some power levels that might actually be true, but for the rest of us, a fine grain of salt should be added to the mix. Before you start in on me telling me I'm wrong, perhaps consider the variations in local environment, antenna differences, not to mention variation in the Ionosphere or alligators, all mouth and no ears running several kilowatts.

The take-away in all this should be that propagation is everywhere. You can use it to hunt for likely contenders and no signal on the band should be ignored as a potential source of propagation information.

One final thought. You can also reverse this. Turn on a web based receiver in some desirable part of the world, pick a frequency and then using your radio, call CQ and see if you can hear yourself across the web.

I'm Onno VK6FLAB

In the past little while you've heard me talk about WSPR, Weak Signal Propagation Reporter and I've told you about signals I've heard across the planet. The longest distance at the time was a HF report, 18656 km from Perth to Pennsylvania, very nice indeed.

I switched to monitoring 6m, 2m and 70cm about a month or so ago.

My reports had been pretty minimal, from my QTH to the suburb next-door and then two suburbs away. Proof that a station is working, but hardly anything to celebrate or even mention.

The other day I came across a report a little further away, Perth to Adelaide, 2142 km away. Not world record beating, or even earth shattering, but proof that 6m propagation does have its moments now and then.

Then a surprise contact, Perth to The Rock, not the one in the middle, or the one with the wave, the one on the Olympic Highway between Wagga Wagga and Albury, 2899 km away with 20 Watts on 6m.

My reports aren't particularly far or amazing. You might recall Wally VK6YS who made a contact on 6m between Perth and Israel. He'd been at it for a little while, longer than I've been an amateur, but not quite as long as I've been the apple in the eye of my mother. 38 years it took for Wally to make that contact.

So why am I making any mention of my little achievement?

Simple really, my station and Wally's station are nothing alike. He had a large beam on 6m located on a property with few noise sources and his patience paid off.

My station consists of a 10m antenna, that is, it's not 10m tall, it's resonant on 10m, and happens to also manage 2m. I've not actually checked to see what 6m on this antenna looks like, perhaps a project for another day, but it sits there, clamped to a metal pergola at the peak of a corrugated iron roof and connected via 20m or so of RG58 coax, cheap RG58 coax, connected to my radio that I use to host F-troop most weeks.

I have to restart my WSPR node monitoring software several times a week since the Windows XP notepad computer it's running on crashes regularly. I have to remember to open the squelch when I finish F-troop and connect the WSPR node back up and I have to make sure that there's enough empty disk-space to make sure that I can actually log stuff.

This isn't a sob-sob story, woe is me, my station isn't a massive station. It's more about that you can achieve these kinds of things with small and minimal resources.

One of my friends is doing really well with a USB TV dongle decoding WSPR on a Raspberry Pi, others are using thousands of dollars of gear and everything in between.

The point is that you too can get started without massive expense. A simple radio, something to run WSPR, which can be a Raspberry Pi, an antenna of sorts and you're on the way to check out what propagation is like around your QTH in your neck of the woods.

Amateur radio doesn't have to be expensive, it doesn't have to be extensive, it doesn't even have to be elaborate, it can just be enough.

I'm Onno VK6FLAB

Over the past year and a half I've been working on a secret project. Today I'd like to share what I've been up to. To set the scene, I'm not doing this on my own, a fellow co-conspirator is Randall VK6WR who became an amateur about 20 months ago. Randall has a long association with the Engineering Development Array and the Murchison Wide Field Array, two of several radio telescopes that are built on one of the few radio quiet areas in the world and located near the future home of the Square Kilometre Array, the SKA.

One day Randall and I started talking, as you do, new amateur, new topics, interesting new fields and ideas. We hit on the idea that radio astronomy telescopes are able to receive 2m signals. This started a discussion about using a radio telescope to receive a moon-bounce signal.

So, the idea was born. Can we create a 5 Watt signal, bounce it off the moon and have it be heard by a radio telescope?

Randall and I have been working on that on and off since our first discussion.

Let me start by pointing out that we've not managed this yet, but we think it's a project worth doing, to forge cross skill exploration by various different groups. I have a strong background in IT and a few years as a radio amateur; Randall brings with him a wealth of radio astronomy engineering expertise, not to mention signal processing, communications and myriad other skills.

We started to do this on the quiet, why talk about something that hasn't happened, might never happen, could be done by someone else who'd claim the glory before we did, and so-on.

I've come to the realisation that while those things all hold true, this is a non-trivial project to achieve and anyone who puts in the work and gets there is welcome to claim the glory.

So, in the 20 months gone by, while both working full time we've done lots of things.

Let's set the parameters. When we first started, both of us were holders of an amateur foundation license. This means hand-keyed Morse, 10 Watts and band restrictions. Because I'm me, I decided that the difference between 10 Watt and 5 Watt wasn't significant enough to make or break this, so we went with 5 Watts QRP. Our license precludes the use of WSJT modes, invented by another radio astronomer, Joe K1JT, so the signal had to be something else. We settled on a manual slow Morse signal. We're using a radio telescope at one end, so it had to be on 144 MHz.

Those decisions made, our first project was to attempt to calculate if we could actually achieve this. Conventional wisdom says no, but our ongoing calculations revised several times since our original effort, show that we're right at the edge of what is possible.

We then started the process of determining if the radio telescope could actually hear moon bounce radio signals. We have a limited field of view, roughly 20 degrees around vertical, so the moon has to essentially be above the telescope. The galactic centre is a very noisy place from a radio perspective, so it has to be at least 20 degrees away from the moon. Similarly the sun, also very noisy, needs to be 20 degrees away from the moon.

That started a process of me learning Python, so I could use Astropy to create a table with observation times that match those criteria. I'm still working on that. Having been a programmer for 35 or so years, I'm not a fan.

We did some manual calculations to do some test runs and had two amateurs send a signal to the moon, which for several reasons, we were not able to detect.

Traditional Earth Moon Earth, EME, communications benefit from ground gain, something like 3 to 5 dB of gain based on the path essentially ducting across the earth, but that requires the moon to be near the horizon, so not relevant for our project, since the moon needs to be overhead. Of course, it might mean that I need to travel half-way across the globe, so I can get the gain, but that's another project for another day.

We get some effective gain from having a very stable signal. You might recall I purchased a high stability compensated crystal module, a TCXO, for my radio a while back, this project is why I did that. Another thing I purchased at the time is mechanical filters which also provide a little effective gain.

We started the process of acquiring some high gain 144 MHz Yagi antennas, but through some miscommunication with the amateur who was selling them at a really nice price, we missed out and haven't yet bit the bullet on another set.

Initially when Randall and I started this, we were working on it on our own, we tried to learn as much as we could and test the waters ourselves. We've been at it now for a while and it's become apparent that this is going to be something that is likely to involve several other amateurs. Some have already been helping, Allen, Allan, Keith, Alek, Leigh and Marcin all contributed time and material. No doubt this list will grow as the project continues.

At the moment I'm still trying to write code to create a calendar of dates that will suit the radio telescope with the restrictions we have in relation to the moon, sun and galactic centre, so we can actually prove that the telescope can hear an amateur radio signal.

We'll need to source some high gain antennas, likely more than two.

Once we've done a one-way test, that is, me sending and the radio telescope hearing, we'd like to do the same but between two QRP stations.

No doubt the road ahead is paved with spikes, potholes and road-blocks, but as adventures go, this one has been sustaining me for nearly two years and so-far it's showing no signs of abating.

I'm Onno VK6FLAB

The ultimate radio shack is a nirvana that most amateurs I've met strive for all their life. One of the many views I've heard on the topic keeps speaking to me, one of minimalism, less is more, what is the absolute minimum that you can use and still call yourself an amateur?

As you know, I've recently moved and my shack was packed up into some boxes and is now slowly being unearthed. At the moment there are two antennas, a radio and a power supply. Keen observers will note that this is the same as it was last week.

I've left well enough alone because of two reasons, one being that I'm trying to catch up on lost work during the move and the time where my internet connection was less than optimal, the other reason being that I've been attempting to work out what I actually want from my shack.

Unlike my previous QTH, my current location affords me more flexibility, much more, as in four to six times more space to call my own. That's not to say that I was previously living in a shoebox and now I'm in a mansion, just that the distribution of space this time around is working out very well.

So, I could go crazy, install computers, screens, multiple radios, a work bench, a soldering station, a weather monitoring station, a contest computer and the likes, or I could spend some time enjoying the breathing space around me and contemplate what I should do with this new found freedom.

Initially I pictured setting up a dedicated DX cluster screen, a propagation screen, write some scripts to show the current maps using something like a raspberry pi, set up a dedicated space for doing contests and figure out how to mount several HF antennas, but the more I think about this, the more I wonder if this is what I really want.

I've said many times that I adore contesting, it's a pull, a challenge, a bridge I have to cross, a mountain to climb, whatever the metaphor you see, but is that all there is about amateur radio that I enjoy? I know that I'm working on several bits of software, another DX project, some research and other activities, all related to amateur radio, but not specifically contesting.

The thing I'd like to attempt to avoid, perhaps foolishly, given my less than latent hoarding tendencies, is the clutter that I see in other shacks. They're perfectly homely places, comfortable, full of interesting things, but I'm wondering what a minimalist shack might be instead, think of it as a "tiny houses" equivalent of getting rid of clutter in my life.

What minimalist successes and failures can you share that helped you along the way?

I'm Onno VK6FLAB

This podcast began life under the name "What use is an F-call?" and was renamed to "Foundations of Amateur Radio" after 206 episodes. To mark what is effectively this, the 500th episode, I considered a retrospective, highlighting some of the things that have happened over the past decade of my life as a radio amateur. I considered marking it by giving individual credit to all those amateurs who have helped me along the way by contacting me, documenting things, asking questions, sharing their experiences or participating in events I attended. Whilst all these have merit, and I should take this opportunity to thank you personally for your contribution, great or small, to amateur radio, to my experience and that of the community. Thank you for making it possible for me to make 500 episodes, for welcoming me into the community, for being a fellow amateur. Thank you.

During the week I received an email from Sunil VU3ZAN who shared with me something evocative with the encouragement to bring it the attention and appreciation it deserves.

By way of introduction, on the 13th of June 2002, Ken, W6NKE became a silent key. Ken was an amateur, an active one by all accounts. I never met Ken, but his activity list is long and varied. Ken became interested in ham radio as a teenager in the 1930s. He was a long time advocate of CW and during WWII he taught Morse code to Navy operators. In 1975 he founded The Sherlock Holmes Wireless Society and was editor of its newsletter, now called "The Log of the Canonical Hams". He received his Investiture from The Baker Street Irregulars in 1981. Ken was an early member of the International Morse Preservation Society or FISTS, he held number 0818. He was the President of Chapter 2 of the Old Old Timers Club, the OOTC for many years. In addition to drawing cover art, Ken also wrote. Lots. 73 magazine features plenty of Ken's articles with titles like: "Inexpensive Vertical", "Don't Bug me Dad" and "The DX Hunter".

Ken was also a poet, which brings us to the way that I think is appropriate to mark the 500th episode of this podcast. I'm confident that you can relate to this contribution by Ken to amateur radio, published in Volume 1, Number 3 of 73 magazine in December 1960.

The Vagabond HAM, by Ken Johnson W6NKE (SK)

A vagabond's life is the life I live Along with others, ready to give A friendly laugh and a word of cheer To each vagabond friend, both far and near.

I travel the air waves, day or night To visit places I'll never sight From the rail of a ship, or from a plane Yet I'll visit them all again and again.

I never hear from a far off land That my pulse doesn't quicken. With careful hand I tune my receiver and VFO dial To make a new friend and chat for awhile.

Africa, Asia, they're all quite near In as easy reach as my radio gear With the flip of a switch, the turn of a knob I can work a ZL, a friend named Bob.

There's an LU4, a fellow that's grand Who's described to me his native land 'Till I can hear the birds, and feel the breeze As it blows from the slopes of the mighty Andes.

I learned of the surf, and a coral strand, The smell of hybiscus where palm trees stand 'Neath a tropical moon, silver and bright From an FO8 that I worked one night.

I've thrilled to the tales of night birds' screams In the depths of the jungle where death-laden streams Flow'neath verdant growth of browns and greens From a DU6 in the Philippines.

The moors of Scotland, a little French Shrine, German castles on the River Rhine Of these things I've learned, over the air Without ever leaving my ham shack chair.

There's a KL7 on top of the world To whom the Northern Lights are a banner unfurled That sweeps across the Arctic night Makes the frozen sky a thing of delight.

Tales of silver and gold and precious stones Ancient temples and molding bones Where the natives, I'm told, are tall and tan By an XE3 down in Yucatan.

My vagabond trips over the air Will take me, well, just anywhere Where other vagabonds and I will meet From a tropical isle, to a city street.

My vagabond's life will continue, I know Through the fabulous hobby of ham radio And one day from out at the world's end We'll meet on the air, my Vagabond friend.

I'm Onno VK6FLAB

Note: The spelling of the poem is as published in 73 magazine.

A little while ago I mentioned in passing that I was considering implementing a parrot repeater to help determine how your radio is performing. Discussion afterwards revealed that not everyone had the same picture in mind, so I thought I'd share with you some of what I'm considering and why.

Most of the modern radio landscape revolves around hooking a computer up to some type of radio frequency capable device. Commonly it's the audio and control signals that travel between computer and radio, but there are plenty of examples where raw data makes the journey, like in the case of an RTL-SDR dongle.

That journey is increasingly made using USB, the cable, not the sideband, and limits are based around the maximum speed that a Universal Serial Bus has. Essentially the amount of data that you can process is limited by how fast your computer can talk to the radio.

For my parrot repeater, I'm imagining a device that can receive RF from any radio and process that signal to determine what the centre frequency is, the deviation, stability, the mode, what ever parameters I end up being able to determine, a whole other discussion on its own. In response, the idea is that the device generates a report and either presents that using text to speech, or as a web-page, or both.

Using traditional methods, this would involve a radio, a computer, some software, connections between the radio and the computer, not to mention power for both the computer and the radio, an antenna and perhaps an amplifier. The picture I have in mind is not anything like that. I'm imagining a single device that takes power and does all I've described inside the one device. No external computer, no audio cables, no control cables, no hard drives, not anything, just a PlutoSDR and a power source connected to an antenna or two.

You might think that's fanciful. As it happens, we already have some of that today. When I run dump1090 on my PlutoSDR, it presents itself to the world as a website that I can visit to see which aeroplanes are within range, where they are exactly on a map, what messages they're sending and where they're going. All of the processing is done inside the PlutoSDR. All I have to do is give it power and an internet connection.

This is possible because the PlutoSDR is essentially a computer with RF. It runs Linux and you can write software for it. Unlike my Yaesu FT-857d, which also has a computer on board, rudimentary to be sure, but a computer none the less, it cannot be altered. I cannot load my own piece of software, launch a web browser and point it at my Yaesu, not without connecting an external computer that in turn needs to be connected to the radio. I might add, that this is is how many repeaters work and how devices that implement AllStar and Echolink manage to make the jump between the Internet and the world of RF.

If your eyes are not lighting up right now, let me see if I can put it in different terms.

The PlutoSDR has the ability to access signals between 70 MHz and 6 GHz. It can do so in chunks of 56 MHz. Said differently, if you were able to consider all of the amateur HF spectrum, from zero to 54 MHz, you could fit all of it inside one chunk of 56 MHz that the PlutoSDR is capable of. You couldn't send it anywhere, since you're limited to how fast a USB cable is, but you could technically process that inside the PlutoSDR itself.

To get the PlutoSDR to see the amateur HF bands you could connect it to a transverter, in much the same way that today many 2m handheld radio owners use a transverter to get to 23cm, except in this case, we're going the other way.

In order to actually use this massive amount of information, you're going to need to do some serious signal processing. Accessing 56 MHz of raw data is hard work, even if you don't have to get it across a serial connection. As it happens, the PlutoSDR also comes with an FPGA. As I've mentioned previously, it's like having a programmable circuit board, which can be programmed to do that signal processing for you. It has the capability to massage that massive chunk of data into something more reasonable. For example, you might be able to use it to extract each of the amateur bands individually and represent them as an image that you might show to the world as a waterfall on a web browser.

Now to be clear, I'm not saying that any of this exists just yet, or fits within the existing hardware constraints. I'm only starting on this journey. I'll be learning much along the way. No doubt I'll be using existing examples, tweaking them to the point that I understand what they do and how they work. I've already been talking about some of this for years. As you might have discovered, this adventure is long with many different side quests and at the rate I'm going I'm confident that this represents the breadth and depth of what amateur radio means to me.

So, if you're wondering why I'm excited, it's because the amateur radio world of opportunity is getting bigger, not smaller.

I'm Onno VK6FLAB

Recently I made a point of coming up with three different names for License Classes in Australia. I proposed Low Power, Medium Power and High Power and then went on to suggest that this could also be a mechanism to update the framework that is Amateur Licensing in Australia. As it turns out, I'm told that this idea is mostly already active in the United Kingdom.

My idea started as a response to an increasing clamour for more privileges for Foundation Licenses. These calls include demands for digital modes and more power. I understand this demand, though I don't particularly share it.

I think that licenses evolve and the world in which they operate changes and that digital modes are an example of that.

I have a much bigger problem with the way that licensees are using their level of license to look down on those who have "only" achieved their Foundation or Standard call. I have personally been told that I should get rid of my silly license and upgrade and it's unusual to meet a new Amateur who doesn't straight off the bat ask me why I haven't upgraded yet.

I've seen the same behaviour toward Standard licensees and I think it's a fundamentally wrong attitude and approach to have.

In my opinion this is a hobby for participants to do what they want to do within the constraints that they have. For some that means getting a higher level of responsibility, for others it means spending time doing deep learning and investigating the boundaries of their achievement.

The notion that there are different levels of license is completely arbitrary and the idea that some are better than others is ludicrous in my opinion. Just because I have a Foundation License, doesn't mean that I am ignorant and just because others have an Advanced License, doesn't make them all-knowing or expert.

If that wasn't enough, the boundaries between license classes are completely subjective, drawn from historic demarcations between VHF and HF, between Build and Buy and between Morse-Code and Not. These lines are getting so silly that they have become meaningless, to the point of absurdity.

If I as a Foundation License holder can go to a shop and buy a Software Defined Radio, then update the software on that radio by using my skills as a programmer, I have fundamentally changed the way the radio operates, even-though I didn't once touch a soldering iron, or open the case. Our regulations have nothing to say on the subject, nor is there any sane way to police such an activity and nor should there be - this is an experimental hobby after-all.

If I buy a radio in kit form and get it shipped to me, put it all together and turn it on, did I build something, or buy a commercially available radio? Where's the line between building and buying commercially available and what at the end of the day does it really matter?

What is so special about the 20m band that prevents me as a mere Foundation Licensee to access that band and what is so amazing about digital modes that make it that I'm not allowed to use it, even though all digital modes are really just analogue audio and there is no certification, training or assessment related to digital modes for any class of license?

My point is that the current licensing system is in my opinion obsolete, it's broken and the persistent baying from the sidelines by Amateurs who think that I'm demanding more privileges is getting tiresome. It's ludicrous to think that we should remain back in the 1970's, when Novice Licenses were introduced, perhaps while we're at it, should we go back to a spark-gap transmitter too?

The idea that your enjoyment in the hobby is affected by my privileges is absurd to the level of being offensive and if you're threatened by my participation in the hobby, it seems to me that I must be making valid points.

I don't want more privileges. I'm happy with what I have. What I want to do is make this hobby better, make it relevant, make it useful, make it accessible and make it stronger.

That's why I proposed to make three license classes, Low Power, Medium Power and High Power, to make some common-sense where none currently appears to exist.

I'm Onno VK6FLAB

Today I'm going to spend a little longer with you than usual, but then, I think this is important and it's good to end the year on a bang.

Have you ever attempted to make contact with a specific DXCC entity and spent some time exploring the band plan to discover what the best frequency might be to achieve that? If you got right into it, you might have gone so far as to attempt to locate the band plan that applies to your particular target. If you have, what I'm about to discuss will not come as a surprise. If not, strap yourself in.

When you get your license you're hopefully presented with a current band plan that is relevant to your license conditions. It shows what frequencies are available to you, which modes you can use where, and what power levels and bandwidth are permitted. It should also show you if you're the primary user or not on a particular band. If you're not sure what that means, some frequency ranges are allocated to multiple users and amateur radio as one such user is expected to share. If you're a primary user you have priority, but if you're not, you need to give way to other traffic.

It should come as no surprise that this is heavily regulated but as a surprise to some, it changes regularly.

Across the world, frequency allocation is coordinated by the International Telecommunications Union, the ITU, and specifically for amateur radio, by the International Amateur Radio Union, the IARU. It coordinates frequencies with each peak amateur radio body. The ITU divides the world into three regions, Region 1, 2 and 3, each with its own band plan. Within each region, a country has the ability to allocate frequencies as it sees fit - presumably as long as it complies with the ITU requirements. As a result, there's not one single picture of how frequencies are allocated.

And this is where the fun starts.

In Australia there's an official legislated band plan, cunningly titled F2021L00617. It contains the frequencies for all the radio spectrum users as well as a column for each ITU region. The document is 200 pages long, and comes with an astounding array of footnotes and exclusions. It's dated 21 May 2021. There's a simplified version published by the Wireless Institute of Australia, which comes as a 32 page PDF. It was last updated in September 2020. When I say "simplified", I'm of course kidding. It doesn't include the 60m band which according to the regulator is actually an amateur band today. The 13cm band according to the WIA shows a gap between 2302 and 2400, where the regulator shows it as a continuous allocation between 2300 and 2450 MHz. The point being, who's right? What can you actually use?

Oh, the WIA does have a different page that shows that 6m "has had some additions", but they haven't bothered to update their actual band plan.

To make life easier, the regulator includes helpful footnotes like "AUS87". This is particularly useful if you want to search their PDF to determine what this actually says, since it only appears 156 times and it's not a link within the document. In case you're curious, it's related to three radio astronomy facilities operated by the Commonwealth Scientific and Industrial Research Organisation, better known as the CSIRO, two by the University of Tasmania and one by the Canberra Deep Space Network. Interestingly the Australian Square Kilometer Array and the Murchison Widefield Array don't feature in those particular exclusions, they're covered by footnote AUS103.

If that wasn't enough. The regulator has no time for specific amateur use. You can find the word Amateur 204 times but there's no differentiation between the different classes of license which means that you need to go back to the WIA document to figure out which license class is allowed where, which of course means that you end up in no-mans land if you want to discover who is permitted to transmit on 2350 MHz.

If we look further afield, in the USA the ARRL publishes half a dozen different versions, each with different colours, since black and white, grey scale, colour and web-colour are all important attributes to differentiate an official document. Of course, those versions are now all six years out of date, having been revised on the 22nd of September 2017. The most recent version, in a completely different format, only in one colour, has all the relevant information. It shows a revised date of 10 February 2023, that or, 2 October 2023 because of course nobody outside the US is ever going to want to refer to that document - seeing as there's only amateurs in the USA, well at least according to the ARRL.

Interestingly the US Department of Commerce, the National Telecommunications and Information Administration, Office of Spectrum Management publishes a colourful chart showing the radio spectrum between 3 kHz and 300 GHz. You can't use it as a technical document, but it's pretty on a wall to amaze your non-amateur friends. The FCC has a band plan page, but I couldn't discover how to actually get amateur relevant information from it.

If you think that's bad, you haven't seen anything yet.

The British are special. The RSGB publishes a variety of versions, each worse than the next. It appears that their system creates a single HTML page for each band, their 32 page PDF is a print out of that and their interactive viewer wraps all that into some proprietary system that makes using it an abysmal experience. Fortunately, they also link to a band plan made by the regulator, presented as a five page PDF which is much more concise and has the helpful heading: "The following band plan is largely based on that agreed at IARU Region 1 General Conferences, with some local differences on frequencies above 430MHz."

Unfortunately it doesn't specify which particular General Conferences apply, but it does helpfully tell us that it's effective from the first of January 2023, unless otherwise shown. That said, 2023 only appears in the headers and footers and 2024 doesn't appear, so who knows what date exceptions exist.

One point of difference is that the RSGB also publishes their band plan as an Excel Workbook. This might start your heart beating a little faster with visions of data entry, sorting, filtering and other such goodies, like figuring out which frequency to use for a particular mode. Unfortunately the authors have used Excel as a tool for making tables like you'd see in a word processing document. Start and Stop frequencies in the same cell, random use of MHz, spacing between bandwidth and frequencies and descriptions intermingled. In other words, this is not an Excel Workbook and it does not contain information in any usable form, unless you want to do some free text searching across the 32 worksheets - what is it with 32 anyway? Perhaps this is their authoring tool and they save as HTML from within Excel or print to PDF. Who knows?

One point that the British do get right is version control. You can see specifically what change was introduced when. For example, on the 6th of March 2009 the 17m QRP frequency was corrected to 18086 kHz. Mind you, there's several pages of updates, helpfully scattered across multiple worksheets. Yes, they're really using Excel as a word processor.

Before I dig into any other countries, I should mention the United Nations Amateur Radio peak body, the IARU, presumably a model that countries should aspire to. The IARU has links to three different sets of band plans. Region 1 breaks the band plan into HF and higher frequencies and the higher frequencies are broken into notional bands, each with their own PDF. Regions 2 and 3 each provide a single PDF, but the Region 3 document is hosted on the Region 2 website. Region 1 documents contain a revision and an active date as well as an author. Region 2 and 3 documents contain a date and are formatted completely differently.

In Germany the DARC attempts to link to the IARU-Region 1 band plan, but the link is pointing at a non-existent page.

In the Netherlands, VERON points at a 2016 edition of the IARU-Region 1 HF band plan and the current Region 1 mixed band plan for higher frequencies.

In Canada the RAC points at a HTML page for each band and presents all the HF frequencies as a single image, yes an image. All the other bands are essentially text describing how to use a particular band. The HF image states that it applies from the first of June 2023, the rest of the pages carry various dates that conflict with each other. For example, the 2m band states on the landing page that it was updated on the 23rd of September 1995, but the page itself refers to a new 2m band plan that was approved in October of 2020. The linked band plan contains all the credit, who is responsible for the plan, naming the entire committee, adding notes and requesting donations, straight from the RAC newsletter, page 36 and 37 of the November / December 2020 edition, rather than providing a stand-alone technical document.

Let's hop back across the Atlantic and see what else we can learn.

In Switzerland things are a little different. Its regulator publishes a frequency allocation plan that is a thing of beauty. It presents as a table on a web page, but it has a search box you can use to filter the frequencies that you're interested in. So if you use the word "amateur", you end up seeing the whole amateur radio spectrum as it exists within the borders of Switzerland. You can also set frequency ranges and as a bonus, if you type in 1 MHz and change the unit to kHz, it actually changes the number to 1000. As I said, a thing of beauty. Oh, and the footnotes? Yeah, they're links and they open a new window with the relevant information, and you can keep clicking deeper and deeper until you get to the actual legislation driving that particular entry. If that's not fancy enough for you, from within the search, you can download an offline HTML copy, you can pick services, rather than use search terms, and the PDF version, because of course there is one, actually has the same active links to footnotes.

That said, it has some idiosyncrasies. It specifies when amateur radio is the primary or the secondary user of a band, except when it doesn't. I presume that this is a regulatory thing and that it's a shared resource, but as an outsider I'm not familiar with Swiss law, but if I was inclined, I could become familiar, since the documents are all written in multiple languages, including English. Another oddity is that some frequencies show no text at all, but I presume that's a bug, rather than by design.

Speaking of bugs, or features, depending on your perspective. Consider the frequency 2300 MHz. Every single document I looked at mixes up how this is shown. Some have a space between the number and the unit, some don't. Some countries put a space between the 2 and the 3, some a dot, some a comma, the Swiss use an apostrophe. Just so we're clear, these are technical documents we're talking about. They're not literary works, there are standards for how to do this, but it seems that the people writing these documents are blissfully unaware of any such references. Even the IARU cannot agree on how to represent the same number, let alone use the same formatting for the same band plan in each of its three regions.

At this point you might come to the conclusion that this is all an abhorrent mess and I'd agree with you. In my opinion, it goes directly to how important our hobby is in the scheme of things and just how little funding is allocated to our activities.

It also shows that there are contradictory sources of truth and not a single unified view on how to present this information to the global amateur community. In case you're wondering why that matters, electromagnetism doesn't stop at the political boundaries of the location where we might find ourselves and if that doesn't matter to you, consider again how you'd best talk to an amateur of any given DXCC entity and on what particular frequency you might achieve that.

So, aside from whinging about it, what can you do about this?

I have started a project, of course I have, that attempts to document two things, well, three. First of all I use the WIA version of the DXCC list - since the ARRL doesn't actually publish that for free anywhere - and use that to track a list of hopefully official frequency allocation documents. I'm also in the process of capturing the content of each of those documents into a database, so we can all figure out what the best frequency is to talk to another country.

I'm still in the design stages for the database, for example, do we want to store a frequency in Hertz, in kHz, or pick a magnitude and store a number? Each of these choices has long term implications for using the tool. Then there's things like discovering which band plan applies to Scarborough Reef, the San Felix Islands and Pratas Island to name a few, since I've really only scratched the surface with the plans I've explored.

I had visions of putting this on GitHub, but perhaps this should be part of the Wikipedia collection and it should live there. I'm still considering the best plan of attack. In the meantime, you can help. Please send an email to cq@vk6flab.com with the official band plan link for your own DXCC entity, and if you have thoughts on how best to structure the database or where this project should live, let me know.

For example, should the database include just band plans, or should we also include things like modes. For example, the official VK calling frequency for 40m is 7.093 MHz. Should that be in the database and should we include the preferred Olivia calling frequency? While looking at that, consider the band labels we use. Australia doesn't have a 75m band, but others do. Some countries refer to the 4mm band, others refer to it by frequency.

So, over to you. Let me know what you think. I'll leave you with a quote by Daren 2E0LXY:

"It is not the class of licence the Amateur holds but the class of the Amateur that holds the licence."

I'm Onno VK6FLAB

The other day I came across an amateur who expressed concern that someone was using a frequency set aside for repeater use with their hotspot. Band plan issues aside, and you are encouraged to send an email to cq@vk6flab.com with the link to the official band plan that applies to your DX entity, in my experience it's not unusual for an amateur who is configuring their so-called hotspot to use such a frequency.

While you might be familiar with the concept of a mobile phone hotspot that allows you to connect a computer through your phone to the Internet, in this case we're talking about an amateur radio hotspot. Similar in that it allows you to connect through the device to the Internet, but different in that this is essentially a device that connects radios to the Internet, and yes, if we're being pedantic then computers and mobile phones also have radio, well spotted.

Anyway, an amateur radio hotspot is a radio with an Internet connection and in that it's much like a modern repeater. Often they use low transmit power, have limited range within a building or vehicle and because of that are hardly "unattended". That said, if you connect a more effective antenna and an amplifier, you could make such a device into a full blown repeater. In other words, the line between hotspot and repeater is likely in the eye of the beholder.

Given that the regulator in many countries requires a license for operating a repeater, or a beacon, I wondered what the official definition of a repeater was, so I went looking. Note that this applies to Australia only, but you'll find the journey illuminating I'm sure.

The current "Radiocommunications Licence Conditions (Apparatus Licence) Determination 2015" does not have either the word repeater or beacon.

The new "Radiocommunications (Amateur Stations) Class Licence 2023" which comes into effect on the 19th of February 2024 uses both repeater and beacon several times but does not define what they are. It has an interpretation section with a note that lists both "amateur repeater station" and "amateur beacon station" and states that the regulator can define terms under section 64(1) of its own act.

The "Australian Communications and Media Authority Act 2005" section 64(1) states that "The ACMA may make a written determination defining 1 or more expressions used in specified instruments, being instruments that are made by the ACMA under 1 or more specified laws of the Commonwealth." It should come as no surprise that neither repeater nor beacon appears in this document.

I then thought to go sideways and search the "Register of Radiocommunications Licences" for a repeater license. It reveals a PDF for a license with all manner of detail, frequencies, power levels, location, antenna type, etc. for a license, but no definition of what a repeater is.

I then looked at the 481 pages of the "Radiocommunications Act 1992". It uses both beacon and repeater. Unfortunately beacon is in relation to the operation of lighthouses, lightships, beacons or buoys. Repeater is in relation to two or more digital radio multiplex transmitters.

I then searched through the "Federal Register of Legislation" for the phrase "amateur beacon station". It returns 27 results of which 9 are in force. I downloaded all 9, including any explanatory text if it was available. In all, 340 pages of legal documents.

Finally we have progress. In the "Radiocommunications (Interpretation) Determination 2015" we find the following definitions:

"amateur beacon station" means a station in the amateur service that is used principally for the purpose of identifying propagation conditions.

"amateur repeater station" means a station established at a fixed location: (a) for the reception of radio signals from amateur stations; and (b) for the automatic retransmission of those signals by radio.

So, if your hotspot is in a vehicle it's not a repeater, but if you have it sitting in your shack, it is.

Similarly, apparently, my 10 dBm WSPR transmitter, which I use solely for the purpose of identifying propagation conditions, is a beacon. Apparently if you have your computer controlling your radio using WSPR, that's a beacon too. You can apparently apply for a license and pay the regulator for the privilege, the price of which went up by 510% according to their own documentation from $29 to $177, no idea if that's a once off or an annual charge.

So, now we have a situation where, apparently, the rules state that I'm not permitted to use WSPR without a beacon license. In fact, the "Explanatory Statement to the amateur class licensing reform instruments" explicitly states that "Subsection 13(2) prohibits the operation of an amateur station for specified purposes, including for the purpose of obtaining a financial gain or reward. The subsection also prohibits the operation of an amateur beacon station or an amateur repeater station under the Amateur Stations Class Licence, and, subject to subsection (3), the transmission of an encoded signal to obscure the meaning of the signal."

I've just hit send on a letter to the regulator asking for clarification. Perhaps you should write one too.

I've also just switched off my WSPR transmitter and if you're one of the 2,312 amateurs who made a WSPR transmission last year in Australia, perhaps you should too.

I'm Onno VK6FLAB

When you joined the global community of radio amateurs you did so with a perspective that represented, at the time, what you thought the hobby was and how it operated. Since then, years, months, even days ago, that perspective has shifted in both subtle and obvious ways.

One of my local amateur radio clubs, Ham College, was specifically formed to provide amateur radio education and license exams. It's where I went to get my Foundation license in 2010 and it's where many of the local amateurs have been taught over the years.

For years I've been semi-regularly visiting Ham College during their Foundation course sessions. The purpose of my visit is to share what it's like to be an amateur, what things you don't really know about before you get licensed, and what things to look out for when you are.

In general I talk about how to find the rest of the community, what you can expect and what to do with your license once you pass the exam. I try to cover the highlights without overwhelming the audience who technically are not yet amateurs at the time I'm sharing my thoughts.

I talk about the endless variety of amateur radio activities, from activating anything that's not moving, or anything that is, depending on the level of adrenaline required, through contesting, camping and bushwalking, antennas, endless antennas and electronics.

I talk about low power versus high power, and about community expectations in relation to upgrading to a "real" license. In case you're wondering, a "real" amateur license is any amateur license, including the Foundation license I hold, the introductory license. In my view, ultimately, this is your hobby, where you decide when and how much you want more responsibility and decide to pursue what this means for you.

I discuss that the amateur radio community is global, attracting people from all walks of life, from submariners to scientists, from tow truck drivers to teachers, aged from nine to ninety, across all languages. I also touch on some of the less fun aspects of our hobby, specifically bullies.

Over the years you've heard me discuss diversity, equity and inclusion in our community and also how there is a vocal minority who make it their mission to present obstacles to anyone who is different in any way. As I've said previously, the only antidote against this intimidation is to call it out and make your views heard, "this is not in the spirit of amateur radio", rather than change the dial and move on. In case you're wondering, changing the dial does nothing to address the issue and has a lasting effect on anyone else on frequency who might feel, or worse, has been, threatened by the bully.

I also point out that this obnoxious behaviour is an exception, even if you feel personally attacked, and what you might do and whom you might talk to. For the record, my door is always open.

Another example of what I discuss is the local amateur news and the weekly net for new and returning amateurs, F-Troop, midnight UTC on Saturday for an hour, a place where you can ask questions and discuss your issues with a supportive international community of amateurs.

As you can tell, I'm not shy in voicing my opinion. Although I set myself a limit of 15 minutes, of late I've been wondering what other things might be of interest to someone who is just taking their first steps on their amateur radio adventure, hours away from taking their exam.

What kinds of things would you have liked to know when you started your amateur journey? Get in touch, my address is cq@vk6flab.com.

Don't be shy, express your opinion, it's the only thing that changes the world. What do you want the amateurs of tomorrow to know today? How would you equip yourself if you had the chance to start again?

I'm Onno VK6FLAB

Today I'm going to talk about magic. In the past I've made mention of the magic that is Amateur Radio. There are those who think that our hobby isn't magic and that everything that we do in this field is understood and documented.

I think that this is both wrong and unhelpful, since there is much to learn, much to discover and much to invent. Amateur Radio isn't dead, it's full of life, full of things that are continuing to develop, evolve and grow.

Let me give you an example.

In radio there is a phenomenon called the "FM Capture Effect". Explaining how you experience it is simple. If you have two FM transmitters on the same frequency, and you're using an FM receiver, one of the FM transmitters will win, that is, you'll hear one and not the other. Unlike in AM and SSB transmissions, where you hear both at the same time, the FM Capture Effect causes the receiver to pick one over the other.

As an aside, it's because of this effect that aviation and HF communication mostly prefer AM based communication. Imagine two pilots trying to talk to the tower at the same time, one is heard and the other not.

Back to the magic. We can describe that this thing happens. We can show it happening, we can even measure the signal strength difference that causes it to happen, 0.17dB according to one document I read. We can use formulas to describe our FM signal, we can use simulations to emulate it, but in the end, the closest we can get to the how and why is: This happens, we know it happens, it happens under these circumstances, but precisely how, we're not sure.

A thesis I read on the subject by Park Soon Sang at the Naval Postgraduate School in Monterey, California, published in 1989, spends many pages saying all these things and finishes off with: "The simulation results establish that the low pass filtering portion of frequency demodulation accounts for the capture effect of FM receivers." and goes on to say: "It is recommended that the capture effect be verified using an operating experimental system in which system parameters can be controlled and accurately measured."

Or in other words, we built a software simulator to learn about this phenomenon. This simulator suggests that the low pass filter causes this, but you really should make an actual set-up to test this.

If I'm less vague, we simulated it, it looks right, but we're really only guessing, so test this in the real world.

Now, before you get all huffy. I'm saying that a phenomenon that has existed since the first FM transmission in 1936 is still being explored and investigated and the jury is still out as to what precisely causes it and what the parameters are.

As Arthur C. Clarke wrote in 1973: "Any sufficiently advanced technology is indistinguishable from magic." -- by that definition, Amateur Radio is clearly magic.

So, when you next scratch your head about what the future of our hobby has in store, the answer is almost certainly covered by the very same author: "The only way of discovering the limits of the possible is to venture a little way past them into the impossible."

Amateur Radio, it's magic and there is more to discover.

I'm Onno VK6FLAB

In the past I've talked about the Standing Wave Ratio, the SWR, and how it describes some of the characteristics of your antenna system. I say system because it's not just the antenna, it's the connection between your radio and the antenna as well. The coax or feed line, their length and how you've connected your antenna, all feature in the performance of the entire kit and caboodle.

As an aside, that's why measuring an antenna with an SWR meter at the bottom of the antenna, while you're bolting it to the top of your mast is likely to give you a different result when compared with the measurement performed at the radio.

During the week I was asked about how cutting an antenna changes the SWR. The question included a quote from the ARRL Single-Band Dipoles page which states:

"If you see that the SWR is getting lower as you move lower in frequency, your antenna is too long. Trim a couple of inches from each end and try again."

The person asking the question, Phil, wanted to know why he was seeing a different behaviour.

I've seen the same myself and until I had the benefit of an antenna analyser it also made little sense to me.

The reason it makes little sense becomes clear once you realise what assumptions you're working under.

When you look for antennas online, or when you buy one, often it comes with a lovely SWR graph. You'll see frequencies on the horizontal axis and SWR on the vertical axis. You'll likely see a lovely mostly horizontal line with a dip downwards at the frequency where you want to use this antenna.

The assumption you will almost automatically make, I know I did, for years, was that outside the graph the line continues on its merry way in both directions. That means that you're assuming that the SWR comes down in one place and the rest of the time it's high.

If wishing made it so.

With the benefit of an antenna analyser you can graph the whole HF spectrum, and depending on the hardware, you might even be able to see VHF and UHF or higher.

One thing you'll immediately see is that the SWR is all over the place. It's up, and down, crazy lines, across the whole spectrum. You'll find enormous highs and some very interesting lows along the way.

It's one reason why I can use an antenna intended for the 10m band on the 2m band.

When you're making an antenna, like a single-band dipole, you might find yourself in a position where your antenna SWR is going up and down like a yo-yo around the frequency where you're wanting to be. The higher the frequency, the more likely that your trimming ends you in a different dip or a different high, outside the one that you're actually looking for.

One other comment. The ARRL quote which is talking about HF dipoles states that you should remove a couple of inches from each end. Let's take that literally, two inches from each end, that's 4 inches in total. Let's call it 10cm between friends. If you're trimming a dipole for 160m, you'll change the frequency by just over 1 kHz, but if you're doing this on 6m, then the same trimming will change the frequency by nearly 1 MHz and if you use that HF recommendation for 2m, the change is almost 6 MHz, so, trimming a couple of inches as the ARRL suggests will work for some dipoles on some frequencies, but might get you completely crazy results for other frequencies.

Now you know, the SWR isn't high across everything except where you care, it's all over the place and sometimes that helps, and sometimes it doesn't.

I'm Onno VK6FLAB

On the 12th of December 1961, before I was born, before my parents met, the first amateur radio satellite was launched by Project OSCAR. It was a 10 kilo box, launched as the first private non-government spacecraft. OSCAR 1 was the first piggyback satellite, launched as a secondary payload taking the space of a ballast weight and managed to be heard by over 570 amateurs across 28 countries during the 22 days it was in orbit. It was launched just over four years after Sputnik 1 and was built entirely by amateurs for radio amateurs.

In the sixty years since we've come a long way. Today high school students are building and launching CubeSats and several groups have built satellites for less than a $1,000. OSCAR 76, the so-called "$50SAT" cost $250 in parts. It operated in orbit for 20 months. Fees for launching a 10cm cubed satellite are around $60,000 and reducing by the year.

If that sounds like a lot of money for the amateur community, consider that the budget for operating VK0EK, the DXpedition to Heard Island in 2016 was $550,000. Operation lasted 21 days.

I'm mentioning all this in the context of homebrew. Not the alcoholic version of homebrew, the radio amateur version, where you build stuff for your personal enjoyment and education.

For some amateurs that itch is scratched by designing and building a valve based power amplifier, for others it means building a wooden Morse key. For the members of OSCAR it's satellites. For me the itch has always been software.

Sitting in my bedroom in the early 1980's, eyeballs glued to the black and white TV that was connected to my very own Commodore VIC-20 was how I got properly bitten by that bug, after having been introduced to the Apple II at my high school.

I'm a curios person. Have always been. In my work I generally go after the new and novel and then discover six months down the track that my clients benefit from my weird sideways excursion into something or other.

Right now my latest diversion is the FPGA, a Field Programmable Gate Array. Started watching a new series by Digi-Key about how to use them and the experience is exhilarating.

One way to simply describe an FPGA is to think of it as a way to create a virtual circuit board that can be reprogrammed in the field. You don't have to go out and design a chip for a specific purpose and deal with errors, upgrades and supply chain issues, instead you use a virtual circuit and reprogram as needed. If you're not sure how powerful this is, you can program an FPGA to behave like a Motorola 65C02 microprocessor, or as a RISC CPU, or well over 200 other open source processor designs, including the 64-bit UltraSPARC T1 microprocessor.

I'm mentioning this because while I have a vintage HP606A valve based signal generator that I'm working on restoring to fully working. Homebrew for me involves all that the world has to offer. I don't get excited about solder and my hands and eyes are really not steady enough to manage small circuit designs, but tapping keys on a keyboard, that's something I've been doing for a long time.

Another thing I like about this whole upgraded view of homebrew is that we as radio amateurs are already familiar with building blocks. We likely don't design a power supply from scratch, or an amplifier, or the VFO circuit. Why improve something that has stood the test of time? In my virtual world, I too can use those building blocks. In FPGA land I can select any number of implementations of a Fourier Transform and test them all to see which one suits my purpose best.

In case you're wondering. My Pluto SDR is looking great as a 2m and 70cm beacon, transmitting on both bands simultaneously. It too has an FPGA on board and I'm not afraid to get my keyboard dirty trying to tease out how to best make use of that.

What homebrew adventures have you been up to?

I'm Onno VK6FLAB

One topic that is longer than all other topics combined is that of antennas. Designing, planning, sourcing, building, tuning, using, you name it, all of this is regular fare in the day of a radio amateur. I've discussed the topic here regularly and no doubt I'll revisit that when the mood or necessity takes me.

One topic that is rarely discussed is that of failure.

About six months ago I moved house. I've been rebuilding my shack, doing all manner of fancy shuffling of gear and yesterday I finally got to the point of getting some HF activity happening. During that process I went through boxes and boxes of stuff, with coax, connectors, wire, nuts, bolts, heat shrink and all the other necessities of being a member of an experimental hobby like ours.

One box contained wire. You know the adage, only two types of wire required in our hobby, cheap wire or free wire with a preference for free. This box was stuffed with wire. Bits with connectors, bits wound around spools, bits in zip-loc bags with labels, bits of random length - lots of bits of random length.

There was even an abortive attempt at labelling dipoles for various bands on the outside of a couple of zip-loc bags, but no idea if the bit of wire in the bag was actually ever tested and resonant on whatever band was on the label, so who knows, they might have just been cut long waiting for another day and another set of experiments and measurements.

I needed around 50 meters of hook-up wire for my HF antenna experiment and it occurred to me when I was hunting through my box that I couldn't look at a spool and tell you how much wire there was. I did a dodgy measurement of one bit, put it on the kitchen scales and determined that another spool was heavier, so it was likely longer, but without bringing in my calculator, doing extra measurements and doing some head scratching there was no way that I was going to get to the point of knowing how much actual wire was on that spool.

In the end I made do with the dodgy piece, soldered some joins, that's a whole other adventure, involving a gas-powered soldering iron and a flame, the flame won, as well as several other breaks and fixes.

While I was in the process of putting up my new antenna experiment it occurred to me that part of the process of experimentation, even of shack maintenance should be the documentation stage.

I have bits of terminated coax, some of it 20 meters long, some longer, some shorter. How much longer, and how much shorter you ask? No idea. But wouldn't it be great if I could put my hands on a piece of kit that I needed that was the length that I expected and not 10 meters over length, or 1 meter short.

In my audio kit, I have started labelling patch leads with their functions, using key-ring tags. I don't expect that to work for plain wire, but it should be a good solution for coax. I could use cable tie labels, but past experience with those leaves the text fading on the label. I've experimented with a printed label with clear heat shrink, but for reasons best known to chemists, the clear heat shrink becomes yellow in short order leaving the label unreadable.

I've heard of people using electrical tape with colour coding, perhaps one ring for every 5 meters of length, but they seem to come undone in the dust when you go camping.

One thing I do know is that this is a recurring problem for me. This is the first time I've actually stopped to talk about it and perhaps it means that I'll get a little closer to a solution.

I'd love to hear what you do to deal with this and how you keep track of the countless different lengths of wire, coax and rope that's lying around your shack.

I'm Onno VK6FLAB

Much of the operation that I've done as a radio amateur is conducted in the field. That is, I tend to either drive my car to a location, or go out with friends and set-up camp to play. After you do this for a while you start to notice the things that you look for in an operating position.

The very first one is accessibility. That is, how easy is it to get there? It's fine coming up with the ultimate location, but if it's an hour's drive away and you've only got an hour to play, you'll spend all your time getting there and you'll be home late.

By contrast, for field days lasting several nights, I've regularly driven more than a hundred kilometres to find the spot, sometime much more than that. The point is that the accessibility changes depending on your available time. The journey to the location can be just as much fun as the destination itself.

How long you plan to be there will determine what antennas you might want to set-up. If you're there for an hour, you'll likely use a vertical on your car. If you're there for the weekend, your antenna farm will be determined by how much wire you brought and what you can hang it off.

Hanging antennas is the next thing. You can bring your own poles, but for height, nothing beats a solid tree. The taller the better. More taller, more better. If you have several to choose from, you get to play with all manner of fun stuff. For one antenna contraption we had three trees that we ran a wire between. They were roughly spaced in a triangle about 200 meters apart from each other. As I recall, the antenna we built, a massive V-beam managed to talk to Europe for most of the weekend.

For another adventure a simple G5RV dipole was hoisted high into the trees. Another was accomplished by strapping a pole to a fence and setting up an inverted-V antenna. Recently we set-up an antenna that was nothing more than a wire running over the ground.

So, generally speaking height is good. You can cheat by having a low tree and a hill. Or a fence and a pole, or a gazebo and tent-pegs. What ever you can do to attach an antenna to will work to some degree. Which reminds me, if your hill is tall enough, it's likely to have a communications tower on it for someone, if not everyone. They're not the end of the world, but they can cause havoc with noise. Depends entirely on what the communication structure is used for. Bear in mind, some of these sites have noisy solar panel inverters or generators, so that too needs to be taken into consideration.

Another factor in picking a location involves water. Setting up a vertical on a jetty is gold. I've made many long-distance contacts using a vertical with a ground wire running into the ocean. Note that you don't have to actually get wet. Being near the ocean is often enough. I've had plenty of success from a beach car-park from a vertical on my car.

In general, man-made objects such as houses, factories, other cars, power lines, generators, boats, camping grounds with solar panels and plenty more are often bad news for HF communications. The biggest disappointment happens when you take the time to go to a site, set up camp, build your antennas, turn on the radio and all you hear is the noise from a nearby source of interference.

That said, you don't need to travel to the ends of the earth either. 15 minutes from my house is a lake with a park. There's a car park which on occasion attracts a motor home with a solar panel, but by enlarge it's a local park with people going for a walk. From a radio perspective, despite homes, businesses, schools and cars nearby, the place is heaven. It's quiet, it has shade, running water, fence posts and I regularly make contacts from there, right in the middle of the city.

That brings me to another aspect. Creature comforts.

Setting up near a busy road isn't fun. Neither is sitting in your car without shade. Having amenities within reasonable distance helps. For example, recently for a field day we set-up within 10 minutes drive from a regional centre. Didn't even notice it was there, happily dropped in for shopping and a meal. Some beers might have been consumed.

That same site also had high voltage power lines near our location. The only difference was that our site was above the power lines at the top of a hill, so we never even noticed them.

Finally, some of this is all about picking a camp-site that's suitable for radio, rather than a radio site that will handle camping. You get better at it the more you do it. If you check back after the adventure, you'll learn some stuff as well, so don't be shy to discuss your experience with your friends.

What ever you do, practice makes perfect.

I'm Onno VK6FLAB

When you explore the landscape of amateur radio you'll discover an endless array of innovation. There's websites with photos and descriptions of activities, places discovered and lessons learnt. If you watch the growing collection of YouTube channels you'll discover videos describing what people have been up to, commenting on videos they've seen and you'll start to notice that people all over the community are pinging off each other. Social media does the same.

If you read an amateur magazine, or a book, you'll unearth references and counter-references, links and credits, descriptions gleaned and tests made, all of them interlinking and adding to the knowledge base that underpins the amateur radio community and society beyond it.

The same is true for on-air activity. Look at contesting for example, you'll hear descriptions from other contesters, sharing their lessons learnt which potentially influence how you do your next contesting activity. The same is true for working DX, operating any digital mode, running an on-air net, running a SOTA activation, anything.

The point being that you are influenced by others and everything you do influences somebody somewhere else who in turn influences the next person who might then influence you. On and on the chain grows.

This chain of knowledge goes back to the early science in our hobby, the works of James Clerk Maxwell who for the first time brought electricity, magnetism, and light together as different manifestations of the same phenomenon in 1864.

The reason we know this is because he published his work and without needing to leave home to see the original, anyone can read it today from the comfort of their living room thanks to the PDF that's on the Royal Society web-site.

The point being that Maxwell documented his work and shared it with the world.

In our hobby we've gone through the process of making our equipment from unobtainium, requiring that the actual components were constructed before you could actually put them together and use them for their intended purpose. We then went on the scrounge for parts from other equipment, acquiring surplus gear and through a phase where you could buy new components off the shelf and attach them to an etched circuit board. That evolved into being able to design a board, ordering it online, having it built for cents and shipped to our door.

Today an increasing component of our hobby evolves around software with its unique property of transience.

Unlike physical components, software is intangible. You imagine how something might work, you describe it in an imaginary language, convert it into something that can be run inside a computer, and if you did it right, the outcome gives you the basis for your next experiment.

When software reaches a certain level of complexity it becomes impossible to remember. You tweak something over here and something over there changes and unless you can keep all that together inside your brain as a cohesive imaginary model, you quickly run into a brick wall.

If you're a software developer you've likely heard of tools like CVS, SVN and git. They are examples of revision control. They're used extensively in software development, but increasingly they're being used to track changes in documents, legislation and places where change is constant.

As an aside, if you load the various versions of legal requirements of your license into revision control, you'll quickly discover that your license is slowly evolving over time, for better or worse. From personal experience, I know doing that for the Radiocommunications Licence Conditions in Australia was very interesting indeed.

Each of these tools gives you the ability to tweak something, track it and if it doesn't work out, revert to where you started your experiment. It's a little like using a soldering iron and a soldering wick, physical undo for experiments.

When I talk about Open Source software, I'm not only talking about the ability to look inside and add functionality, I'm also talking about accessing the history that goes with that.

Open Source software generally only works if it comes with a revision history, a trail of discovery outlined right there on your screen showing what worked, why and how it came about. There's often options for showing who made what change, which changes happened at the same time and the ability to extract that particular change. All essential ingredients for experimentation.

Closed Source software does all those things, but privately. It too likely uses revision control tools, even the same ones as Open Source, but the discoveries are held in-house, behind closed doors, used by a select few. The software evolves inside the organisation, but there's no insight for or from the outside world.

Of course, everyone is entitled to keep their stuff secret, but if you want to make a contribution to society outside the life of your walled garden, the only way forward is to publish and share your work like scientists have been doing well before the Royal Society held its first meeting on the 28th of November 1660.

Share if you care...

I'm Onno VK6FLAB

One of the oldest global aspects of our hobby, other than actually using the radio, is the QSL bureau. It uses a postcard-like system to confirm that two stations made contact, sent via the postal service as a so-called QSL card. Of course, that only works if you have each other's address which after World War II was somewhat difficult. As a result the QSL bureau was born.

Intended as a single point of contact for a country, a local QSL bureau consists of one or more volunteers, paid staff or contractors, who act as the distribution point for incoming and outgoing QSL cards. If you and I agreed to confirm our contact via the bureau, my QSL card to you would be sent to the VK outgoing QSL bureau, which would hold my card until there were sufficient outgoing cards from all over Australia to your country to package them all up and send them to the incoming QSL bureau in your country.

Your QSL bureau would then wait until there were enough QSL cards for your region to send it on, where it would eventually get into your hands in a variety of ways, via the postal service, through your local club, or at a local hamfest where the QSL bureau might have a stall. Your QSL card to me would make a similar, reverse, journey.

This process could take weeks or sometimes years.

Although not fast, this worked for many decades, but once electronic communications and computers started appearing, combined with increased costs associated with privatised international postal services, the wheels started coming off.

Getting access to historic documents has proven challenging. I can tell you that over the years the IARU, the International Amateur Radio Union, has coordinated and controlled how the QSL bureaus should work. For example, a resolution adopted in 1985 and updated in 2009 "strongly encouraged" its member societies to accept incoming QSL cards for all amateurs in their country, regardless of affiliation. It also instructed QSL bureaus to only send cards to the official QSL bureau if there was more than one.

Several years ago, the IARU administrative council recognised several trends, among them the environmental impact of unwanted cards generated in bulk by computer logging software, lower levels of adoption and ultimately the closing of some smaller QSL bureaus after being overwhelmed by undeliverable cards from increasingly popular holiday DXpeditions.

In September 2018, the IARU adopted resolution 18-1 that stated that it "resolves that member societies are encouraged to continue to offer QSL bureau service in their countries, exchanging cards with the bureaus of other member-societies, for as long as doing so is economically justifiable, and further resolves that amateurs are encouraged to adopt confirmation practices, including but not limited to using electronic confirmation systems, that reduce the volume of unwanted and undeliverable QSL cards being introduced into the bureau system."

This resolution took effect on New Year's Day, 2019. I'll also note that the IARU has its own year 2000 issue, having been in existence for nearly a century, its resolutions are named after the last two digits of the year followed by a sequential number, so resolution 25-1 could refer to 1925 or 2025, but I digress.

The internet has introduced several confirmation processes. The most vocal of these is "Logbook of The World", or LoTW. I'm not a fan and haven't been for some time. I'll get into why in a moment. Other contenders are eQSL.cc, qsl.net, qrz.com, clublog.org and others that have yet to steal the limelight. If I've forgotten the one you run, let me know.

Saying that I'm not a fan of LoTW is understating it. Recent ARRL ransomware payments aside, why do I need to legally prove beyond a reasonable doubt that I made contact with some random amateur? Why does this need to be authenticated, signed with a time-limited certificate and verified with 100 points of identity and why do we continue to roll out new and interesting procedures for what is essentially a postcard saying that on this day, time and frequency we made contact using this mode for the purposes of .. wait for it .. our hobby?

The eQSL website has an interesting statement: "One of the problems with an e-mail based system is that there is no security inherent in that mechanism. Anyone can purport to be P5ABC, and you'll have a difficult time verifying it."

So what .. and what made you think that the postcard ending up in your letterbox was guaranteed to be from P5ABC?

If you're going to the effort of pretending to be P5ABC, what harm does that do in the scheme of things? For that matter, how do you know that the station you talked to on-air was actually P5ABC? I ask because I've spoken to an amateur who recently did some HF direction finding during several popular DXpedition pile-ups. They discovered that there were several stations purporting to be the DXpedition that were not.

So. Right now we're in a situation where many if not all amateurs are connected to the internet. Most will have an email address. You already know mine, cq@vk6flab.com. If we made contact on-air, send me an email. If what you wrote matches my logs, I'll send you a reply to confirm it.

How do you get the address? One possible approach is to create an online email database where you could submit the email address associated with your callsign and you could look-up a station to contact them.

Another is for member societies to offer email addresses, the ARRL and the WIA already offer this service to current members.

I'll also point out that one of the reasons that the QSL bureau was instigated in the first place was because some addresses for amateurs were not available. If you make contact today and you want to send them an email confirmation the question to ask is simple: "Hey, what's your email address?"

Will that cover everyone?

Nope. Neither does the current system. What it achieves is that my personal private identifying information isn't stored at the ARRL if I'm not a member. Besides, in my opinion a list of email addresses combined with callsigns is hardly something worth getting excited about, unless of course it's used by manufacturers to send out product announcements and discount codes. We should be so lucky.

If you have a better idea, you know how to get in touch. What I can say is that this is the ultimate decentralised QSL system, not unlike the contact you made on HF.

I'm Onno VK6FLAB

Internet access across HF radio

In the mid 1980's there was this thing called a Bulletin Board System or BBS. You would connect your computer to a gadget called an acoustic coupler that you would sit next to a telephone. You'd pick up the handset, dial a phone number and wait until there was a squeal in your ear. Then you'd push the handset into the rubber cups on the coupler and watch as your computer started putting characters on your screen.

Now, truth be told, my first foray was the next generation of this, an actual modem where you didn't actually have to touch the telephone, instead, the device could dial on your behalf using so-called AT commands.

And if we're being totally honest, I never actually connected to a BBS. My adventures with global communications started with Usenet News in 1990, but I'm here to make a point, I promise.

Amateur radio is a hobby that is for experimentation. One such experiment is a thing called packet radio. Before you roll your eyes about ancient technology, this gets very cool, very fast.

At its most basic, packet radio is about digital radio communication. Until not that long ago to play you needed a thing called a TNC or a Terminal Node Controller. When I got my license in 2010 I was told that this was a magic box to make digital communication possible between a radio and other radios and amateurs.

Right now, many people are playing with WSPR, Weak Signal Propagation Reporter as well as FT8, both examples of things intended to get specific chunks of information exchanged between two stations. What if I want to chat, or send a file, or a picture?

There are tools like "js8call" which is experimenting with the idea of using FT8 to chat, but what if I told you that there's a better way?

Written by John WB2OSZ, named after a canine that became extinct 9,500 years ago, "direwolf", is software that implements an expensive piece of 1980's hardware, a TNC, that runs just fine on a $5 Raspberry pi. It's been around for over a decade, the oldest date I can find is March 2013 though undated versions before that exist.

It's an example of a so-called software-modem, simple to get started, and it implements the essential pieces of packet radio. It's currently running connected to my radio and I can see packets of information scrolling past. In this case I'm tuned to the local APRS, or Automatic Packet Reporting System frequency of 145.175 MHz.

It's the same information that you can see if you point your web browser at aprs.fi

While that's great, it's just the beginning. Tune to another 2m or 70cm frequency and you can use it to connect to a BBS being run by a local amateur, or, you can tune to a HF frequency and connect to one run somewhere else.

Direwolf also supports a technology called KISS, Keep It Simple Stupid, yes really, developed by Brian WB6RQN, Phil KA9Q, Mike K3MC and others. KISS allows you to connect a modem, like direwolf, to a computer and use technologies like TCP/IP, the primary language of the internet, across a radio link, any radio link.

Let me say that again with different words. You can use your HF radio to browse the internet. No proprietary modes in sight, weak signal, error correction included, all open source, all free, all ready to go.

While we're singing its praises, direwolf can also act as an iGate, an interface between radio and services like aprs.fi, a digipeter that receives and re-transmits APRS data and plenty more.

It gets better.

What if you wanted to use something like RTTY, PSK31, Olivia or some other mode? You could use "fldigi" instead of direwolf since it too supports KISS.

To be fair, there are lots of moving parts here and I've glossed over plenty. This isn't intended to discuss precisely how to do this, rather that it's possible at all and has been for quite some time.

I can't wait to attempt to browse the internet using my radio, for nothing other than the thrill of attempting it.

I wonder if I can do this with Morse Code as the underlying protocol. Only one way to find out.

I'm Onno VK6FLAB

The hobby of amateur radio is one of experimentation and change. For decades this came in the form of circuit diagrams, components and scrounged hardware from anything that wasn't bolted down. New functionality came with the aid of a soldering iron.

More recently, functionality comes from participation in the global electronics market where you can buy any radio you like and have it shipped to your door within hours at an unbeatable price.

Mind you, buying all those unbelievably cheap radios does start adding up and if you want to use more sophisticated hardware, that too is possible, at a price, somewhere between $50 and a new Porsche. Whilst that's an option for some, for the rest of us, there are better and cheaper ways.

Of course it doesn't stop there. If you connect any radio to a computer, you can use whatever software you like to encode and decode any signal you can imagine. With a traditional radio connected to a computer you can make it participate in hundreds of different so-called digital modes.

Before I continue, let's look at radio in a slightly different way.

Consider an antenna as a continuous source of voltages that are amplified, filtered and demodulated in some way by a radio. You can think of the combination of antenna, radio and computer as a stream decoder. To decode a signal in a new way requires a new decoder, which you could build from components or as I've said, buy online.

During the week I've continued experimenting with GNU Radio. If you're unfamiliar, it's a toolkit that allows you to build so-called flow graphs that can process a signal stream. Think of it as a box of Lego that you can put together to build any type of decoder.

Let me say that again.

Imagine that you want to decode or transmit a mode like FreeDV, M17, APRS, Olivia, Contestia, or Hellschreiber. With the GNU Radio toolkit, all of this is possible and you won't need to buy new hardware or bust out the soldering iron every time you want to experiment with a new mode.

If you have been playing with digital modes already, you'll likely point out that you can already do this today by using software running on a computer, and that's true.

What that doesn't tell you is that this comes with a very specific limitation, namely that all those modes require that they fit inside a single audio channel because all those digital modes you might be familiar with are essentially using an SSB or FM signal with the audio generated or decoded by a computer.

Even if you have a modern radio like for example an ICOM IC-7300, you'll still be limited in what modes of transmission you can make. ICOM limits the transmit bandwidth to 2.9 kHz. Flex Radio appears to double that to 7.9 kHz, but numbers are sketchy. The point remains, most current amateur radio technology is based around the notion that a mode essentially fits within a single audio channel and a very narrow one at that.

So, why does this matter?

If you run out of FT8 space on a band, right now you need to change to an alternate frequency to play, but you'll only be able to see the stations that are using the same alternate frequency, as long as they fit within the bandwidth of an audio signal. If you wanted to check out the main frequency, you'd have to change frequencies and keep switching back and forth. Using this idea, monitoring all of FT4, FT8, WSPR and all CW beacons, all at the same time becomes unimaginable, not to mention costly if you needed a radio for each band and each mode.

What if you wanted to use another mode that took more than about 4 kHz, like say a 5 MHz wide DVB-T signal which you could be experimenting with on 70cm?

Or, what if you'd like to compare a repeater input with its output at the same time? Or compare two repeaters together? Or find the best band to operate on right now?

The point being, that there are things that simply don't fit within a single audio channel that you won't be able to play with using a traditional radio.

As it happens, that too is a solved problem.

Remember that I mentioned that you can think of an antenna, radio, and computer combination as a stream decoder?

What if I told you that an SDR, a Software Defined Radio, is essentially a device that translates antenna voltages into numbers which you can process with GNU Radio?

Whilst that does imply replacing your radio, you don't have to jump in at the deep end to start playing and even if you do decide to buy new hardware, you can get your toes wet with all manner of self build or commercial kits. Even better, you can start with the gear you already have today and become familiar with GNU Radio and when you're ready to expand your station, you can add in an SDR and continue to use the same tools to experiment.

Not only that, you can do interesting things by combining what you already have. Consider for example the idea of using an RTL-SDR as the receiver with a traditional radio as the transmitter. You could decode all of the FT8 signals on a band and transmit where there was space to do so.

The point being that you can do this one step at a time. Every time you download or build another GNU Radio flow graph, you can have a new decoder and as time goes on, you'll be able to decide what hardware you might want to pair it with.

To be clear, I'm talking about the gradual change from component based radio using audio interfaces into software based radio. It's not like we haven't done this before. Anyone recall spark gaps, or valves?

The future of experimentation is bright and it's filled with bits.

I'm Onno VK6FLAB

The first time I came across the concept of antenna polarisation was a decade before I became a radio amateur. To connect to the internet while driving around Australia I became the proud owner of a portable satellite dish. Portable in the broadest sense of the word, 150 kilos with a dish that's 2.4m high, 1.8m wide, steel base, electronics, power and patience to erect and point.

The dish has a receiver and transmitter component that needs to be aligned, just so, in order to be able to have two-way communications using 5 Watts into geosynchronous orbit. The transmit and the receive are exactly 90 degrees offset from each other. One is called horizontal polarisation, the other vertical.

The first thing to observe is that if you're using the wrong polarisation, it doesn't really work well. We'll get into what is right in a moment. Depending on where you you ask, the definition of not working well can be as bad as 40 dB loss.

Just let that sink in for a moment.

If you want to punch through with more power, you'll need to bring 10 kilowatt with you for the receiving station with the opposite polarisation to hear 1 Watt.

If you're using a VHF or UHF FM radio in your car, you're likely to have a vertical antenna. The combination of a repeater on a hill and a radio in a car adds up to much more than the the two alone. The line is blurred today because repeaters are very popular and home-base stations are becoming smaller and smaller by the week, so vertical antennas for VHF and UHF at home are today just as common as they are on cars.

It wasn't always that way. In fact, in HF, it's almost never that way and if you're a fan of Tropospheric Ducting or long distance VHF, then you'll also shy away from vertical antennas.

Let me explain.

If you want to erect a HF antenna and you want it to rotate and you want it to be high enough off the ground, you'll build the simplest mast you can get away with. Imagine a HF Yagi. It's got several elements, long to short along a boom, rotator somewhere in the middle. If you mount this Yagi horizontally, your mast will be around half a wave length in height.

If you mount the same Yagi vertically, aside from the height discussion - should it be mounted higher or not - now your mast becomes another interfering element within your Yagi. The steel wires that keep your mast standing will also interfere with the Yagi elements and your elements will be closer to the ground where they can potentially cause harmful radiation.

So from a mechanical perspective, putting a Yagi on a mast vertically is not trivial.

From a radiation perspective you may theoretically get some gain, but adding an element or two will make up for any potential gain that a vertical arrangement interacting with Earth might assist with.

There's another reason. The ionosphere. It sounds like a smooth billiard ball, it's drawn as a uniform layer around the earth, but in reality, clouds and their appearance are much more likely to represent the actual surface shapes that the ionosphere presents to your radio waves.

A signal coming in one way is unlikely to come out at the other end in the same way and vice versa.

That's HF. On VHF and UHF a horizontal signal and a vertical signal when they're used with line of sight are pretty similar, but once you get beyond that, a horizontal signal will travel further, how exactly is a story for another day. If you're doing point to point VHF or UHF contesting, horizontal is the way to go.

What about a single HF vertical?

It's excellent for a portable station, it is simple to set up, works in all directions, but it means you'll be able to hear all the local man-made noise as well, so find a quiet spot near the beach if you can.

So what's the right way? Almost always horizontal, except on cars or when you're on a DXpedition on a beach sipping pina collada and getting caught in the rain.

I'm Onno VK6FLAB

It's been raining around here for a while now. Not in the order of 40 days and 40 nights, but significant. Mind you, I have lived in a place where it rained every day for 57 days, but I digress.

Water, plenty of it and often in all the wrong places.

Being a radio amateur you come across water in many aspects of the hobby, sometimes it comes in handy, like lubricating your throat while you're calling CQ, or as a ground plane for an antenna, other times, not so much, like when it enters the shack and causes the black smoke to escape from your pride and joy.

As I said, I'm no stranger to rain and in my travels I've encountered plenty of it. I managed to travel around Australia for a couple of years and I took with me a two-way satellite dish with sensitive electronics attached. Living in Australia I planned for dry. This place is dry. Often very much so, but as it turns out, dry doesn't mean without humidity, storms, rain or in one case hail.

These experiences told me a little about protecting electronics from the weather.

I should add a disclaimer here, I'm not a certified weatherman, nor am I certified in waterproofing, water ingress, or any other guarantee. So, if you do as I say and it breaks, you get to keep both halves. That said, I have some thoughts on the matter and I wouldn't be me if I didn't share them.

Water is generally everywhere. It gets into everything and it's one of those silent killers. Electronics and water rarely mix, unless you submerge the electronics in mineral spirits, or if you seal your electronics in circuit board lacquer. Even then, there are few guarantees.

The best you can hope for, in my experience, is to plan for failure, hope for success.

Finding where water gets in is often the hardest part of keeping it out. Sealing off your electronics from the world in a waterproof anything will trap heat, which in turn will cause condensation, which will ultimately cause rust and destruction of your priceless electronics.

Giving your stuff time to acclimatise is a very good idea. For example, if you have a radio stored in your garage and you bring it indoors, leave it there for several hours, if not overnight. Unless you live in Alaska with an in-floor heater to prevent your engine block from freezing, your garage is cold, your home is warm, the combination causes condensation. Alternatively, if your garage is hot, and your home air-conditioned, the reverse is true and condensation will still happen.

Water has a habit of finding its way into anything, encouraged by gravity. That means that a length of coax, run into your wall will attract a stream of water along the coax, straight into the connector and into your wall, or between the core and the braid, or into your radio, or some other undesirable place. If you create a low point before the connector, like a drip-loop, a place where water would have to go up before it can do damage, you'll likely solve the issue, but don't discard the effects of wind which can cause water to go uphill.

Connectors are magnets for water. Most connections in use in amateur radio have little or no waterproof rating. There are special waterproof connectors about and you may consider using those, but alternatives like self-amalgamating or rubber tape, which you wind tightly around a connection and in doing so, stretches and glues itself together to keep the water out. These tapes are generally not stable in the ultraviolet of the sun, so you may have to wrap that sealed connector in another layer of tape, plumbing or electrical tape is one solution.

Based on the experience from national coax installations, the way to do this is with three windings of rubber tape, followed by two of plumbing tape. Think of up as towards the weather and down as away from the weather and make the windings like this:

Wind the rubber tape three times around the connector, up, then down, then up again.

Seal this from the sun with two windings of plumbing tape, down and then back up towards the weather.

For endurance, add a cable-tie to keep the tape in place when the glue eventually fails. This will ensure that water always runs away from the connector.

The way to remember this, for a positive result, there are three ups and two downs.

If you ever get your coax wet, that is, the end, be prepared to cut off a length to protect your gear. Coax rot is real and is essentially the rusting of the braid, the shield or the core and it spells bad news for your gear.

Operating portable is a whole other subject in relation to weather, but the same principles apply. Keep the temperature stable, keep the water out, protect from rain ingress along the coax and you'll likely be able to have a good time and come home without any damage to your gear.

There is a persistent idea that rice can help you dry electronics. While it does have some effect, it's slow and by the time it's removed the water, the damage will already have been done. Air drying is much more effective. Use a fan, keep it running and you'll have a better chance of rescuing a drowned circuit.

As for electricity and water, they don't mix, they can kill and you should know better.

I'm Onno VK6FLAB

Technology is a moving feast. New ideas spring new inventions which in turn change our lives. Amateur Radio is at the forefront of such inventions. Radio Amateurs have been until recently the only soldering iron brigade around. We've been building things for over a hundred years and we continue as a community to think of new ideas and ways to make them happen.

For example, we take technologies like AllStar Link, EchoLink, Wires and so on all in our stride. We think nothing of having our radios connected to each other using techniques other than radio spectrum.

In November 1997, when iPhone still meant Internet Phone, an inquisitive 22 year old amateur called Dave Cameron VE7LTD came up with a way to link a radio to the Internet and the first three Internet Radio Linking Project stations were connected to each other and the now global network of IRLP nodes was born.

Dave built a DTMF decoder which allowed remote control of a computer and the radio that was attached to it, and made it possible to send the audio from the radio to the sound-card of the computer, which in turn sent that audio in digital format across the Internet to a similarly equipped system where the audio was turned back into a radio transmission.

This bridging idea took off and many different systems were developed, many of which are in active use today.

The various systems all use some form of Voice over IP to transmit audio across the Internet, but there are many variations on how the audio gets to the system in the first place.

In IRLP - as I mentioned - the audio can only come in via an Amateur Radio. EchoLink uses a similar system, but in addition to Amateur Radio as a source, you can register your callsign and use several different applications on your computer or mobile phone to link into the network. AllStar takes this idea further, instead of making a point-to-point connection, the AllStar system is based around an open source telephone exchange called Asterisk and it's used to link together the various systems.

Other variations also exist. The idea of using Voice over IP techniques spawned a whole set of radio technologies that use similar methodologies to compress voice and then instead of transmitting it across the Internet, use radio waves to send them from one radio to the next. Technologies such as D-Star, System Fusion, MotoBro and DMR built on this idea. Of course these technologies also use the Internet to share information and connect users across the globe.

There is some contention around these systems. Many Amateurs consider them to be "Not Real Radio", but then I suspect if you look at the birth of SSB, you'll find die-hard CW operators with a similar complaint. The same is true for low power propagation modes like WSPR which aren't real radio because you cannot have a QSO.

Other issues in the technical sphere also exist. The IRLP software is closed source. You can only buy IRLP hardware from one place and it doesn't allow you to connect in any other way than via a radio. EchoLink now charges for conferences being registered in the system. In the past I've already spoken about Fusion, D-Star and MotoBro and their restrictions around interoperability, licensing and closed source nature.

From a practical perspective, there are also concerns about the use of these systems in the case of massive failures during local disasters and the like. If the Internet is down, many of these systems will simply become local radio networks. Coverage could perhaps be extended by creating a local mesh network, but HF radio still very much has its place in our world.

For me this is all about learning and innovation. Ultimately which system you use is up to you.

I live in a software world where Open Source rules for good reason and my vote will always go to Open Source. To be clear, I'm not adverse to making money, we all have to pay the rent, but making innovation and invention secret is not the way to go in our hyper-connected world.

I'm Onno VK6FLAB

Today I want to talk about Politics. I can hear you groan from here, so hold your horses, stow your tar and feathers and put your pitchfork back in the barn.

Amateur Radio is a hobby. It's to do with electronics and physics and the ionosphere and other cool stuff. Some people call Amateur Radio a thousand hobbies in one and that's a pretty good description.

Underlying Amateur Radio are the people. Those who have spent their time studying, learning new skills, doing tests, passing exams, as well as people who are interested bystanders, not necessarily licensed, but drawn towards the bounty that Amateur Radio as a hobby represents.

An interesting phenomenon among people is their varying level of passion. Some people are passionate about their dog, others about their children, others are passionate about cars, or baking, or in our case, passionate about Amateur Radio.

Passion has been explained to me once as a "big elephant". You sit on its back and it takes you where you want to go. Gentle nudging makes the elephant change direction, but if it gets excitable or startled, it'll go where ever it wants and all you can do is be a passenger and hold on tight.

If you mix passion and Amateur Radio, there are times when that will result in heated discussion about the merits or pitfalls of a particular radio, an antenna or some other aspect of the hobby.

If you group people together into radio clubs then those clubs are made of passionate individuals who come together to promote the objects of their club. As people group and discuss, opinions differ, goals morph and change and aims and objectives are blurred.

Before long, you get special interest groups, proponents and opponents, elections, board meetings, stoushes, mis-management, legal action and the whole gamut of life.

To complicate matters, Amateur Radio uses a public resource, radio spectrum. This is generally managed and maintained by a regulator, which in turn is generally managed by, politicians.

What this means is that as a Radio Amateur you should not be surprised to learn that politics plays a part just as it does in the rest of society.

I can still hear you muttering from here. My In-Box hasn't yet seen any derisive emails, but I can picture their arrival.

What does this all mean?

It means that Amateur Radio is not one thing. It never has been and never will be. For each individual there is a personal path to find and a journey to travel. For some this means that they'll become the Contester of the Year, for others it means that they'll invent a new gadget, others will use Amateur Radio as an excuse to travel the globe and others will use it to be the big cheese in their club.

Your role is simple.

Remember that this is a Hobby. That it's your hobby and that you have as much say in it as the next person.

Remember also that this Hobby exists because we've been given access to a public resource and it's our responsibility as Amateurs to conduct ourselves in a manner that befits that public trust.

I'm Onno VK6FLAB

If you've heard the phrase "shortwave listeners", you might have wondered what on earth that was all about.

It relates to the length of a radio wave used to transmit information. The length of a radio wave is tied to its frequency. The longer the wave, the lower the frequency.

When radio amateurs talk about bands, like for example the 40m band, we're talking about a range of frequencies where the wavelength is around 40m. From a frequency perspective, this is around 7 MHz. The 160m band, at about 1.8 MHz, or 1,800 kHz is considered the beginning of the short wave bands.

This implies that there are longer waves as well. If you've ever seen or owned a mid 1980's transistor radio, you'll have seen the notation MW, which stands for Medium Wave, today it's called the AM band. Older radios might have the notation LW, or Long Wave.

The medium wave band is a broadcast radio band that runs between about 500 and 1,700 kHz. The wave length is between 600 m and 170 m.

When radio was still in its infancy, there was also a popular long wave band, with wavelengths between 800 m and 2,000 m, or 150 to 375 kHz.

Today much of that has gone by the wayside. With the advent of digital radio, in Australia it's called DAB+, Digital Audio Broadcasting, the whole idea of "wave" has pretty much vanished.

Some countries like Japan and the United States are in the process of discussing the phasing out of the AM broadcast band. Much of that appears to be driven by car manufacturers who claim that the AM band is no longer useful or used, but forget to tell anyone that they really want to stop having to put AM radios in their cars because it's difficult to isolate the electrical noise from their modern contraptions in order to make it possible to actually listen to that band.

If you ask me, it's a good incentive to make electronics RF quiet, something which is increasingly important in our wirelessly connected world.

This might lead you to believe that all activity on air is moving to higher and higher frequencies, but that's not the case. The properties that made long wave and medium wave radio possible in the early 1900's are still valid today. For example, there are WSPR or Weak Signal Propagation Reporter beacons on the 2200m band, or at 136 kHz.

Whilst your RTL-SDR dongle might not quite get down that low, most of them start at 500 kHz, you don't need to spend big to start playing. My Yeasu FT-857d is capable of tuning to 100 kHz, plenty of space to start listening to the 2200m band, even if I cannot physically, or legally, transmit there.

If you want to build your own receiver, you can check out the weaksignals.com website by Alberto I2PHD where you'll find a project to build a receiver capable of 8 kHz to 900 kHz using a $50 circuit board.

If that's not enough, there's radio experimentation happening at even lower frequencies. Dedicated to listening to anything below 22 kHz, including natural RF, with a wavelength greater than 13 km, Renato IK1QFK runs the website vlf.it where you'll find receivers and antennas to build.

Given that most sound cards operate up to around 192 kHz, you can start by connecting an antenna to the microphone port of your sound card and use it to receive VLF or Very Low Frequencies. On your Linux computer you can use "Quisk" to tune.

There are VLF transmitters on air. For example, SAQ, the Grimeton Radio Station in Sweden opened on the 1st of December 1924. Capable of 200 kW, today it uses about 80 kW and transmits twice a year on 17.2 kHz.

While we search for higher and higher frequencies, there is still plenty of fun to be had at the other end of the radio spectrum. Consider for example that VLF or Very Low Frequency radio waves, between 3 and 30 kHz can penetrate seawater.

I'll leave you to explore.

I'm Onno VK6FLAB

When you are absorbed in a hobby like amateur radio it's easy to lose track of the world around you. I freely admit to spending many hours on this hobby and it wasn't until I spent some effort taking stock that I discovered just how much time I spent.

The fifth clause of the Amateur's Code attempts to formalise this behaviour and I confess that it's taken me several years to find a more reasonable balance. Let's review the original 1927 published version of this clause. It reads:

The Amateur is Balanced. Radio is his hobby. He never allows it to interfere with any of the duties he owes to his home, his job, his school or his community.

It's interesting to note that in one of the oldest documents describing our community it refers to our activity as being a hobby. I'm noting this because there have been plenty of treatises written on the notion that amateur radio is a public service and not a hobby.

This clearly states that in the opinion of the General Counsel of the ARRL in 1927, Amateur Radio is a hobby and frankly, I'm fine with that.

The 2022 ARRL handbook removes the reference to hobby and words it:

The Radio Amateur is BALANCED...radio is an avocation, never interfering with duties owed to family, job, school or community.

The ARRL website reintroduces the concept of a hobby like this:

The Radio Amateur is BALANCED...Radio is a hobby, never interfering with duties owed to family, job, school or community.

I'll note that the definition of avocation is "a hobby or minor occupation" and I'm not sure what the clause gains by using a word that I had to look up in the dictionary. Consider for a moment if your first language isn't English, why use "avocation" when "hobby" is the same thing?

The original used the phrase: "never allows it to interfere with any of the duties he owes", this puts amateur radio as a hobby at the bottom of the pecking order in the list of things you do. The 2022 version waters this down to "never interfering with duties owed", essentially elevating the hobby above some of those other duties. I don't think that this is an improvement.

I'm a fan of amateur radio, but I think that in the scheme of things it needs to take the place of a hobby, not an activity that has the ability to be prioritised over any of your other duties. If it does, where is the line? What is more important and what isn't? Should this be something that we in our code of conduct endorse? What's next, telling amateurs specifically what they should be doing? I think not.

One thing that's worth exploring is the concept of "job". A job is your occupation, tow truck driver, radio astronomer, submariner or accountant. The original meaning, going back to the 1550's is "an activity that an individual performs in exchange for a specific fee or payment".

What if you don't have a job? What if you're retired, unemployed or have some other lifestyle?

What if we replace the word "job" with "work", defined as "a physical or mental activity that is performed in order to accomplish or produce something"?

This could make the fifth clause look like this:

The Radio Amateur is BALANCED...radio is a hobby, never allowing it to interfere with any of the duties owed to home, work, school or community.

It's short and sweet, uses simple language and it covers everything that the original document was attempting to achieve, and as a bonus it no longer requires you to have a job.

I'm Onno VK6FLAB

In Volume 1 - Join the hobby - follow my initial journey through the community, what to buy when you start, how to participate in the community, things to practice, what the first steps look like once you have a license, playing in radio contests, encouragement and sharing.

Search for my callsign - VK6FLAB - on your local Amazon store to have a Look inside.

I'm Onno VK6FLAB

About a year or so ago I received a message from a friend of mine. The message asked if I would have or could find a use for some amateur radio gear from their active amateur father who became a silent key. That started a sequence of events that leads us here, today. In the year that followed that message I became the grateful owner and archivist of an amateur shack that belonged to Walter VK6BCP (SK). Walter had two calls that I know of, VK6BCP, last logged on the DX cluster on the 5th of April 2012. His other call, from Switzerland, was HB9CAI, last reported on the cluster on the 23rd of February 2005.

The more I dig into Walter's collection of all things that make a shack, coax, connectors, boxes with spares, power supplies, odds-and-ends, the more I find a kindred spirit. I never met Walter, but he and I share the same sense of order. We sort things in the same way, we have the same kinds of things on hand and it's gotten to the point where it's hard to tell where his shack ends and mine begins.

Walter's shack contributed several radios, some of which I loan out to beginning local amateurs, I took one with me on a recent trip and I've been using one to run a weekly net to see how this particular radio works and what quirks exist.

One of the requirements to actually switching on that last radio brings me to bread crumbs.

I needed a power supply to make the valves glow - well, the digital display - but you get the idea. There was a suitable power supply on the shelf, but I had no idea when it was last switched on, if it worked, if it would set fire to my shack, what the state of it was. It looked near new, no scratches on the paint, bit dusty, but it looked as well loved as my own power supply, which is now coming up to nearly a decade old.

I picked it up and the power supply rattled. Never a good thing in a device that has no moving parts. On closer inspection I noticed that only four of the fourteen screws were holding the case together and it stopped me from plugging the thing in and turning it on - with a stand-by fire extinguisher at the ready - mind you, I might have been slightly exaggerating with the fire extinguisher.

I did what any enterprising radio amateur would do in that situation, I got out a screwdriver and extracted the four remaining screws and lifted the lid. I wasn't sure what I would find, but nothing prepared me for what was there, though Walter being Swiss should have.

Inside this lovingly maintained power supply I found a little zip-loc bag with ten screws. The ones missing from the case. This was the source of the rattle.

I also found a disconnected fan lead, actually, it had been purposefully cut and folded back.

Now why do you suppose that was?

For my money, Walter knew this power supply well. His power requirements didn't need a fan - truth be told, mine probably don't either - and to keep everything in one place and to remind himself that he'd made a modification, he'd done the smart thing, make it obvious that something had been modified.

He could have put a sticker on the case, but over time that would have faded. He could have carved his initials into the case and carved an instruction, but both of those would have reduced the aesthetics of the power supply and if his callsign ever changed, or if he reconnected the fan, he'd have to start again.

What I found was something that gave me pause to consider how you manage to document what you've done, not only for yourself, but for others who might stumble on your modification. I'm certain that Walter never considered that one day I'd be telling you this story and thanking him for his preparation, but that's exactly where we are.

You might come away from this wondering what the point was of all this?

The point is, you can prepare your shack for events that might not happen. You might lose your memory, become a silent key, or have a beginner borrow your kit. You'll never know what it will be. What you can do is make it possible to discover that something has been changed. Walter could have just as easily put all fourteen screws back in and I would have never been any the wiser. I might have thought that the fan only came on under load, instead of not coming on at all, ever, because the lead had been cut. My first sign of trouble would have been magic smoke escaping and perhaps the need for a fire-extinguisher.

Leaving bread crumbs for discovery is a really simple and helpful way to document your adventures.

Thank you Walter VK6BCP (SK) - it's been a pleasure to know you through your shack.

I'm Onno VK6FLAB

The recent "incident" at the ARRL in which it disclosed that it was the "victim of a sophisticated network attack by a malicious international cyber group" brings into focus some serious questions around our community in relation to identity and privacy.

Let's start with your callsign. Right now in Australia you can use the official register to look for VK6FLAB. When you do, you'll discover that it's "Assigned to Foundation". That's it. No mention of who holds it, where it's registered or how to contact the holder, none of that.

In the case of my callsign, because I haven't surrendered my apparently now legally useless license, you can still search the previous system, the Register of Radiocommunications Licenses and discover that it's held by me, but as soon as it expires, that record will vanish and the relationship between me and my callsign will be lost to the public.

Also, there are no dates associated with any of this. You cannot use the current or previous system to discover if I held my callsign in November 2010 or not. In case you're wondering, no, I didn't, I was licensed a month later. Right now if you look for VK6EEN on QRZ.com, you'll see that it's linked to CT1EEN, but when was that information last updated? I know for a fact that I became the holder in November 2020. It appears that Sam CT1EEN used it around the turn of the century, about 24 years ago, but precisely when and for how long, is unclear.

So, from a public disclosure perspective, the links between me and my callsigns are tenuous at best.

Before I continue, I will point out that this is not unusual. For example, you can see the number plate on my car as I drive down the street, but most people don't have the ability to link it to me.

Similarly, Ofcom in the United Kingdom released a list of allocated amateur callsigns after a freedom of information request. It's unclear if this information is updated, or if it requires a new request each time. Like Australia, the dataset contains the callsign, the type of license and when the record was last updated. Nothing else.

In contrast, the United States has a full license search that returns name, address, issue and expiry dates. Japan offers both a search tool and downloads. Interestingly you can see if a callsign was previously licensed and when, but not by whom.

No doubt each country has their own interpretation in relation to how this is handled and as was the case in Australia, this is ever changing.

This leaves us with an interesting phenomenon.

We use callsigns on-air to identify ourselves, but the relationship between the callsign and our identity, let alone when, is not guaranteed for a significant proportion of the amateur community.

So, how does this relate to the ARRL incident?

Radio amateurs like to make contacts with each other and collect those contacts like you might collect stickers or postage stamps. For decades we've used QSL cards, essentially a postcard sent from one amateur to another to confirm a contact. When you collect enough cards, you can apply for an award, like the DXCC, showing that you made contact with one hundred different so-called DX entities.

In the era of computing, some organisations, like the ARRL, came up with the idea of using the internet to exchange these contacts instead of using a postcard. This reduced delays and was presented as a system to make the process more secure by requiring that people electronically sign their contacts, but could only do so after identifying themselves using traditional means, like providing copies of their license, their passport, etc. The ARRL called it Logbook of the World, or LoTW, and it was adopted by the amateur community around the globe.

While the ARRL continues to state that it only holds public information on its member database, it has made no such assurances about the LoTW system. There is personal and private information that the ARRL has and there is no indication at all what happened to it.

Other systems such as QRZ, eQSL, Clublog and Hamlog offer similar systems with various levels of authentication and verification. A new player, HQSL, is confusing the issue by offering cryptographically signed QSL cards, boasting that their system is decentralised and not restricted to any single service, but immediately requires that you sign-up with Hamlog to get going.

So, we have several organisations offering electronic logging, contact confirmation and security which claim to guarantee that this callsign contacted that callsign at a time and date, on a band, using a mode.

One problem.

None of this is real.

For starters, there is no guarantee that the station operating VK6FLAB was me. There is also no record guaranteeing that I'm the holder of VK6FLAB, or any proof that I am who I say I am. There is also no guarantee that the person confirming a contact between VK6FLAB and you is me. So, we're creating a phantom secure system that's attempting to fix the wrong problem.

In golf, when you start playing for rankings, rather than a round at the 19th hole, the process used to verify your score is dependent on peer review. You cannot mark your own score-card, someone else does.

In amateur radio we've built this electronic house of cards to track whom we've talked to and when, but it's a mirage when looked at closely.

While a DXCC award is worth nothing more than a personal achievement, we cannot go on pretending that identity verification services like LoTW are real, nor can we continue to accept that organisations like the ARRL should demand and store valuable identity information.

I'm Onno VK6FLAB

During the weekend I participated in a contest. Before you get all excited, it was only for a couple of hours over a few different sittings and while I had plenty of fun, of the eleven QRP, or low power, contacts I made, nine were on VHF and UHF, two were on 10m HF. Mind you, 3,200 and 3,500 km contacts are nothing to sneeze at.

It has been a while since I've actually been on HF, so long that it felt like turning on a new radio and getting used to it all over again. If you're not sure what I'm describing, let me elaborate. A new radio takes a few goes to calibrate your ear and brain to learn what you can expect to hear and work. On some radios if you can hear the other station, you can work them. On others, unless they're pegging the S-meter, you've got no chance. QRP adds an extra layer of challenge.

A few hours earlier I'd been discussing HF band conditions and one comment that stuck in my mind was that the bands appeared to be more quiet than normal. At the time, nobody could put a finger on why or how, but there appeared to be a general consensus that this was the case.

So when I tuned to 10m, after having switched off my beacon, which I promptly forgot to turn back on for 36 hours or so, I went hunting for stations to contact. I heard a few, but their signals were very weak. Noise levels were amazing, very quiet, but stations were very low down. I thought nothing of it, given the discussion we'd just had, and persisted and as I said, I made two contacts.

Since contacts were hard to come by, I started playing with another experiment I'm working on. Specifically I'm using something called USBip to connect to some USB devices across my network. The way it works is that you plug the devices, like a CAT cable and a USB sound-card into a Raspberry Pi, then using another computer, you can access those devices wirelessly as-if they're physically connected to the other computer. This is useful if you don't want to subject an expensive computer to any stray RF that might be coming in via a USB port. I've written some hot-plug support for this, so you can just connect and disconnect USB devices without needing to fiddle. You'll find the code on my github page.

Given that stations were few and far between and not staying in one place, I moved to a local AM broadcast station, so I could test the USBip sound-card link and all I heard was absolute garbage audio coming from that station. I turned on another radio and it too had the same rubbish audio. After a couple of hours fiddling with RF-Gain and still not getting anywhere I started searching online for an answer. One thread, 27 posts long, seemed to describe what I was hearing. Bill N8VUL supplied the answer: "Make sure AGC is on"

So, no. It wasn't, on either radio.

Why it was off on both radios I will never know. It did make me start exploring again just what other settings I have access to on my radio and what they sound like. Turns out that there's not a lot to be found that has any basis in fact. There were a lot of videos showing amateurs pushing lots of buttons uttering phrases like: "Can you hear the difference?" with nothing much materially changing.

The closest to something useful was a YouTube video by Doug N4HNH, called "ATT, IPO, [and] RF Gain" in which he shows some of the effects of each of those options on a Yaesu FT DX 5000. One thing I noticed is that the radio has a neat display that shows the signal path as it passes from a selected antenna through those options and more, highlighting which ones are in use.

I started hunting around to see if such a block diagram exists for my FT-857d. Unfortunately I didn't manage to find any such diagram, not even for another radio. The closest I got was the image on page 30 of the FT DX 5000 Series Operating Manual.

I did learn that the attenuator on my radio is 10 dB and it doesn't function on 2m and 70cm. As for the AGC, the user manual doesn't help much. It states that it's used to disable the Automatic Gain Control and normally it should be left on. There's some discussion around the interaction between the "RF Gain" knob and the AGC, but I must confess that finding useful examples of this managed to elude me.

At this point I have no idea what the difference is between the block diagram on the FT DX 5000 and my FT-857d, other than the obvious single antenna port and plenty of missing features. I find it surprising that for a radio that was introduced over 20 years ago, this kind of information appears to be lacking. Especially since it would help any new amateur operate their radio better and understand the impact of each particular setting on the signal that they were hearing.

If you know of any such resource, reach out, my address is cq@vk6flab.com

Meanwhile I'm going to spend some quality time with my radio and the manual and see what other hidden gems I can find and if you know me at all, you'll know that this isn't the first, second or even third time that I'm going through the manual of a radio that I've now owned for nearly as long as I've been an amateur.

I'm Onno VK6FLAB

This week I'm going to talk about a Digital Mode you can use with any Amateur License, or even without an Amateur License. You can set-up your radio, hook it to a computer and the Internet and after installing some software, you can join the Weak Signal Propagation Reporters.

So how do you start, what does it do and how can it help you?

First of all, WSPR, pronounced Whisper, is a way of encoding information and transmitting it across the spectrum. At the other end a radio receives that signal, sends it to a computer where a piece of software attempts to decode and then log it.

This Digital Mode, invented by Joe K1JT, is one of several modes that are gaining popularity across the Amateur Radio community because the beauty of this mode is that it's so unobtrusive that you're unlikely to actually hear it if you were to tune to a dedicated WSPR frequency.

If you want to find out what your station can hear, you can set yourself up as a dedicated receive-only station and report your findings to a central database where others can share your information and learn what propagation is like at that particular point in time.

Of course, it also means that you can use the same information to learn what propagation looks like in your neck of the woods with your radio and your antenna set-up.

There's even an option that allows you to have your radio automatically change frequency - known as band hopping - and listen for WSPR signals across the bands that you allocate.

If you like, you can go to the wsprnet.org website right now and do a search for my callsign, VK6FLAB and see what stations I've heard since I turned it on. Go on, have a look, I won't mind.

My station is set-up to do band hopping across all HF frequencies all day and night and during the grey-line it only listens to 80m, 40m, 15m and 10m, since those are the frequencies my license allows me to transmit on and I'm particularly interested how they work at sun-rise and sun-set.

You might have heard me before talking about how the noise at my home is atrocious. Nothing has changed, it's still abysmal, but WSPR signals are coming in and being decoded.

If you want to do this, you'll need a radio - any radio will work, a computer with a microphone socket and a way to pipe the audio from the radio into the computer, I'm using a 3.5mm male plug to 3.5mm male plug - you don't need a fancy audio interface, you're only listening. If you can connect an interface cable, your computer can also change frequency for you, but that's not needed to get started.

Make sure that you turn the volume right down before you plug anything in. Connecting a headphone output directly into a microphone input can blow up the port if you're not careful and WSPR doesn't need much in the way of volume. The software helps you get it set right, so read the manual before you start.

Once you've set-up your radio and your computer, you can watch the signals coming in on a waterfall display, a graphical representation of the audio and frequency that shows strong signals in red and no signal as blue. You'll find that turning up the volume too high will actually reduce the ability to hear signals.

I'm keen to learn what I can hear and how many stations my simple 10m vertical antenna can hear across the Amateur Radio spectrum.

I'd love to hear your weak signal stories and see what you can hear. As I said, it seems I'm becoming a short-wave listener after-all.

I'm Onno VK6FLAB

In my ongoing software explorations I've discussed that Software Defined Radio or SDR is a fundamentally different way of dealing with radio. It's been in use across non-amateur circles for decades. Your mobile phone has an SDR on board for example.

The original term of "digital receiver" was coined in 1970, "software radio" was coined in 1984 and in 1991 Joe Mitola reinvented the term "software radio" for a planned mobile phone base station.

So, this idea has been around for half a century and in amateur radio this idea is also catching on. You can buy a few pure SDR devices today, some hybrid ones, or you can begin to experiment in a more indirect manner using your traditional radio and a computer.

One of the things that sets this idea of a software defined radio apart from anything we've done so far is that the bulk of the signal processing is done in software. That sounds obvious, but it's really not.

One of the impacts of this idea is that you can improve your radio communications by either writing better software, or by using a faster computer. Unless you write software for a living, these things aren't immediately obvious, so let me explain.

Imagine that you've written software that detects beeps in a particular slice of audio spectrum that's being fed to your application. As you write better software to detect those beeps, you get a better digital mode, one with a better chance of being decoded, or using radio terms, it has a better signal to noise ratio.

If that's not a familiar term, signal to noise ratio is the a measure that describes the difference between a wanted signal and the background noise. Higher signal to noise means that you can better distinguish between the two.

If you stand in a room full of people talking and you use your hands to cup your ears towards the person you want to hear, you've increased the signal to noise ratio and your chance of understanding them has improved.

As you write this software, it gains complexity. As you deal with more maths, more samples, more tests, you end up running out of time to make your decoder return a relevant answer. There's no point in having a real-time signal being decoded late. If it were to take say 10 seconds to decode 1 second of audio, then the next second would be 20 seconds late and the one after that would be 30 seconds late.

That's where a faster computer comes in.

If you have the ability to do more maths, or do the same maths at a higher resolution, you will essentially improve the reception of your radio without ever needing to change your antenna or anything on the circuit board.

Think of it in another way.

Imagine that your tool has access to 2.3 kHz of audio. It's the equivalent of a Single Side Band audio stream. If you break that down into 23 chunks of 100 Hz each, you can deal with the average of 100 Hz of audio for each calculation. If you have a faster computer, you might be able to break that down into 230 chunks of 10 Hz each, or 2300 chunks of 1 Hz. So instead of doing calculations across 23 chunks of audio, you're doing it across 2300 chunks.

Why is this significant you might ask?

Well, in a traditional radio you get one bite at the cookie. You get to design and build your circuit and then package it and sell it. The end result is something like my FT-857d. It does what it does well, but it will never get any better.

However, if I plug that same radio into my computer, I can extract the audio and do stuff with it. If I get a faster computer, I can do more stuff. I don't have to change my radio, or my antenna, or even my shack. Most of the time I run a different application and I get a different result.

I will point out that I'm deliberately ignoring where and how the RF gets to the computer, or where that computer actually is, or what operating system it's running, since none of those things matter to get an understanding of how changing software can change the performance of your radio.

I've said this before and I'll say it again: "The SDR earthquake will change our hobby forever"

Before I go. I'm not for a minute suggesting that your current radio is obsolete. If it were legal, a spark-gap transmitter could still exchange information today, but if you want to explore what might be just over the horizon, going down the SDR path by connecting your radio to your computer is a really nice place to start.

I'm Onno VK6FLAB

Boating adventures

The other day I was on a boat. That's right, me, on a floating thing, on the water, the ocean actually, steering and everything. I should confess that when I was younger I spent most weekends sailing as a sea scout in Holland.

Managed to become a bootsen, that's the bunny in charge of a boat. Sea scouts, zee verkenners, was also my very first introduction to amateur radio through JOTA, Jamboree On The Air, where scouts across the globe come together, though it didn't make quite as much impression as breaking the middle finger on my right hand an hour later, but that's a story for another day.

So, me, on a motorboat, a tiny one, but still.

You may be wondering where this is going, trust me, it's relevant.

In preparation for my boating adventure I pulled out my trusty hand held radio, a waterproof Yaesu VX-7R. If you're not familiar with it, it's a tiny radio, capable of tuning between 500 kHz and 1 GHz, not quite DC to Daylight, but impressive nonetheless. I have it programmed for all registered Australian repeaters. One state per group in case you're planning to program yours.

One of the in-built options is to select Marine Channels. They're numbered from 0 to 281. I've looked in the past and in Australia the channel numbers don't follow any logic as simple as that. Numbering is all over the place, 84 channels as far as I can tell, I had to count them, the highest channel number is 2086 and there's channels with names like AIS 1 and AIS 2 rather than numbers.

If you're a yachtie, you're laughing your head off right now, but I'm making a point about Amateur Radio. We don't do channels here, well mostly we don't, unless we picked up an ancient radio cheap from somewhere and re-purposed it for Amateur Radio, but to coin another sailing term, by and large, we do frequencies.

So, here's the thing. My radio is perfectly able to transmit on marine frequencies and being a responsible person I thought it would be smart to bring my radio, just in case. I will confess that I didn't. After discovering that the marine documentation was all about channels, and decoding frequencies was beyond a quick look-up, I thought that it would be prudent to leave my radio at home. I had a mobile phone with me, was staying near to the marina and the boat owner actually supplied a radio.

So here I am, a semi-experienced radio amateur, completely clueless about marine radio. While I was figuring out how to tell you about this, I managed to find the government website which referred to a training website which referred to a user guide that actually had a list of channels and frequencies side-by-side. You'll be pleased to learn that channel 16 on my radio, the emergency marine channel is on the same frequency as the official channel 16 in Australia.

My point is this. We have a common interest in communicating. In the case of an emergency it would be useful to know what marine channels relate to what frequencies and how we as radio amateurs can help if required. It also means that we as radio amateurs are not the all knowing beings we believe ourselves to be. Of course we already knew that, so we keep learning.

I know I'm going to learn how marine radio channels work. I'll probably have a look-see at other channel spectrum users and see how they relate, so I can know how their system works in case I ever need to.

I'm Onno VK6FLAB

As you might know, a little while ago I started a new project.

"The Bald Yak project aims to create a modular, bidirectional and distributed signal processing and control system that leverages GNU Radio."

In embarking on this adventure I've been absorbing information as I go whilst explaining what I've learnt to anyone who will sit still long enough. Credit to Glynn VK6PAW and Charles NK8O for their patience.

For most people, me included, the introduction to GNU Radio happens via a graphical user interface where you build so-called flowgraphs. These are made up of little blocks that you wire together to get from a Source, where a signal originates, to a Sink, where it terminates.

Each of these blocks does something to the signal, it might be a filter, an amplifier, it might encode or decode a signal like FM, AM, Wideband FM, or some other modulation like Phase Modulation or OFDM, Orthogonal Frequency Division Multiplexing, a way of transmitting digital information using multiple channels. It's used in places like WiFi, ADSL and DSL, Digital Television as well as modern cellular systems.

Those blocks generally expect a specific type of input and generate some particular output.

After you save your design you can run the flowgraph and behind the scenes some magic happens. Your visual representation of signal flow is translated into either Python or C++ and the resulting application is what is actually run, which is why the user interface that you design your flowgraph in is cunningly named, GNU Radio Companion.

So, what if you want to do something that doesn't yet exist? As it happens, that's where I came across a YouTube video by John VE6EY called "GNURadio Embedded Python Block" which neatly describes a fundamental aspect of how the GNU Radio framework actually operates.

One of the blocks available to you is one called "Python Block", which you can add to your flowgraph just like any other block. What sets it apart from the others is that you can open it up and write some Python code to process the signal.

When you first insert such a block, it's already populated with some skeleton code, so it already does something from the get-go and that's helpful because if you break the code, you get to keep both parts.

Seriously, it allows you to figure out what you broke, rather than having to worry immediately about how specifically the code is wired to the outside world, which let's face it, is not trivial. If you're a programmer, think of it as the "Hello World" of GNU Radio.

If not much of that means anything, think of it as a variable electronic component. If you need it to be a capacitor, it can be that, or a transistor, a whole circuit, or just a filter, all in software, right there at your fingertips and no soldering required.

Now I'm under no illusion that everybody is going to want to get down and dirty with Python at this point, and truth be told, I have a, let's call it "special" relationship with the language, but that is something I'm just going to have to get over if this project is going to go anywhere.

For my sins this week I attempted to recreate the intent of John's video on my own keyboard and discovered that debugging code in this environment might be tricky. It turns out that you can actually print out Python variables within your code and in the GNU Radio environment they'll show up in the console inside the companion window, which is handy if you committed one of many Python sins, like say attempting to compare an integer against a list. Don't ask me how I know.

One thing I'm planning to attempt is to get the same thing going for C++ output. By default GNU Radio Companion uses Python, but you can change it so instead of generating Python, it can generate C++. Whilst I have no immediate need for that, I do know that at some point it's likely that I will, like say when I want to run something on an embedded processor, or some other contraption. So, whilst I have nothing to lose, I want to try out the boundaries of my new toy, besides, I have form, in testing boundaries that is.

I'm Onno VK6FLAB

Sometimes you learn mind boggling things about this hobby, often when you least expect it. Recently I discussed having my 20 mW WSPR or Weak Signal Propagation Reporter beacon heard on the other side of the planet, in Denmark, 13,612 km away. That in and of itself is pretty spectacular, but it gets better if you consider just how weak the signal was by the time it got there.

In radio communications there is a concept called path loss or path attenuation. Until recently I understood this to mean the things that impede a signal getting from transmitter to receiver. That includes coax and connector losses, refraction across the ionosphere, reflection off the surface of the planet and diffraction around objects.

It turns out there is another factor called "Free Space Path Loss" to consider. It's loosely defined as the loss of signal strength between two antennas. The name sort of implies that something happens to the signal in free space, which is odd if you know that in space, radio waves, regardless of frequency, travel without loss and will travel pretty much indefinitely.

So what's going on?

To get started, think about a dome lawn sprinkler, one of those little round discs that sits on the ground with the hose connected to the side. You turn on the tap and the water sprays in all directions. If you're really close to the sprinkler when the tap is turned on you'll get sopping wet almost immediately, since most of the water will hit you directly. This is particularly fun in the heat of summer on New Years Day in Australia, not so much in the middle of winter on the other side of the globe.

If you stand a couple of meters away, you'll still get wet, eventually, but it will take much longer, because most of the water isn't hitting you. If you stand even further away and assuming the water still gets that far, it will take even longer.

A small towel and a big towel will both take the same length of time to get wet if they're held at the same distance from the sprinkler, but if you wring them both out, you'll discover that the big towel captured much more water during the same time.

In radio communications we can combine these two ideas, the distance and the size of the receiver, to describe free space path loss.

The further away from the transmitter you are, the less signal is available to you to capture since much of the signal is not heading in your direction and the bigger your antenna, the more signal you receive. The bigger the antenna, the lower the frequency, which is why you'll discover that free space path loss is dependent on both distance and frequency.

To give you an idea of scale, the free space path loss for 28 MHz over 13000 km is about 144 dB.

While the name "Free Space Path Loss" implies loss of signal across the path in free space, the loss is not due to distance as such, rather it's caused by how much the signal is spread out in space. Similarly, there isn't more loss because the frequency is increased, it's that less signal is captured by the smaller size or aperture of the antenna required for a higher frequency.

So perhaps a better name might be Spherical and Aperture Loss, but then everyone would have to learn how to spell that, so "Free Space Path Loss" it is.

I'll point out that this is the minimum theoretical loss, in reality the loss is higher than this, since it also includes all the other parts of the path loss which are things that we can control, like coax and connector loss, and things we can improve by frequency selection, like ionospheric reflection and refraction which depend on solar conditions.

The one aspect of path loss that we have no control over is the "Free Space Path Loss", so perhaps that's why we don't talk about it very much.

I'll mention that in path loss calculations often antenna gain at the transmitter and receiver are used to reduce any path loss figures. If I have an antenna with 6 dB gain, then that reduces my overall path loss by 6 dB, which is why we spend so much time and effort figuring out what antenna to use when we get on air to make noise.

I mentioned that the free space path loss for my beacon between Australia and Denmark was about 144 dB. This means that my 20 milliwatt signal arrived in Denmark as a -131 dBm signal. That might not mean much, but that's the equivalent of about 80 attowatts. If you're not sure how big that is, 1 milliwatt is 1 quadrillion attowatts, a 1 with 15 zeros. Said another way, 1 watt is 1000 milliwatts, 1 milliwatt is 1000 microwatts. 1 microwatt is 1000 nanowatts, 1 nanowatt is 1000 picowatts, 1 picowatt is 1000 femtowatts, 1 femtowatt is 1000 attowatts.

It might come as a surprise, but these numbers are not unusual. Don't believe me? When your radio shows an S0 signal on HF, it is defined as -127 dBm, so we deal with tiny numbers like this all the time, we're just not quite aware of it on a daily basis.

Remember, my numbers are theoretical only, to give you an idea of scale. In reality everything in the path between the transmitter and receiver affects what ends up at the other end and might make the difference between hearing someone, or not.

I'm Onno VK6FLAB

A while ago I set up a WSPR, or Weak Signal Propagation Reporter at home. Before I go into the details, WSPR is an amateur radio protocol that allows stations to transmit their callsign, location and power level and for receivers around the globe to decode those and upload the results to a central database. It's a great way to see what you can hear and what propagation is like.

A couple of months ago the regulator changed the Australian License Conditions Determination, the rules of engagement around amateur radio and now all licensed amateurs in Australia can even set-up a transmitter although I haven't yet. Receiving is plenty of fun and anyone can do that.

Initially I used a piece of Windows software to track the contacts but to me it was like ordering a courier with an 18-wheeler to pick up a postage stamp. I looked around an found a piece of software that runs nicely on a single board Raspberry Pi computer. The software is called rtlsdr_wsprd, it's a mouthful, but it works nicely on a Pi with an RTL SDR dongle. The dongle I have is capable of using all HF frequencies up to 1766 MHz, so I can technically hear the 23 cm band, though I haven't actually heard any stations there.

I created a list of all the published WSPR frequencies and I listen to a frequency for fifteen minutes, pick another frequency at random and do it again, all day, every day. My log for this installation goes back about eight months and I get about a hundred contacts every month or so.

You might think that's a lot of contacts, but really it's not. The antenna is indoors, it's under a metal roof and while it's on the second floor, it's far from ideal, but it works surprisingly well.

What have I learned from this experience?

I've heard 36 different stations, across 11 countries and 23 grid squares, the furthest was G0CCL, a club station in Cambridge in the United Kingdom which was transmitting on 20m with 5 Watts. I heard it 14750 km away.

There are plenty of other things that I can extract from this. The most popular band is 20m, it accounts for nearly 70% of the contacts I heard. Surprisingly, I am also hearing contacts on 80m, as well as on every other amateur band that my receiver can hear. The 6m band is pretty popular too, nearly 13% of the stations I heard.

For my receiver, between 4am and 6am in the morning was the best time to hear something, together they account for just under 20% of the contacts. Locally the worst time is 8am in the morning.

From the data I've collected, April and May were the most active, accounting for nearly 70% of the contacts.

I must point out that the log is not continuous, there's gaps when the logging station wasn't switched on and when I was switching antennas and locations, so using the statistics I've given you here for your own station are probably not going to work quite the same.

The WSPR mode isn't perfect. It will happily decode rubbish and report on that, so I've manually filtered out the bogus information, like for example a grid square XI97LK, or callsign 3KE/21XWK, where neither the location or the prefix are real.

I can tell you that I was surprised that my station can hear 80m on the little telescopic rabbit-ear antenna supplied with my dongle. That same antenna is also fine at hearing 6m, so I'm pretty happy with that.

One thing that this little experiment reveals for me is that a cheap dongle is a perfectly fine way to start playing with a limited budget. It offers the opportunity to explore the RF spectrum using modern tools and techniques. Much of what I describe is absolutely possible with a traditional radio. Originally I had my station set-up like that. It consisted of my Yaesu FT-857d, a 12 V power supply, a CAT cable, an audio interface and a computer.

In stark contrast, my current set-up consists of two things. A Raspberry Pi with an RTL SDR dongle plugged in.

While this set-up cannot transmit, neither could I at the time. Since then there have been advances in both. There are all-band WSPR transmitters for a similar cost to a Pi and a dongle. Power it up, configure it and you're good to go. I'm eyeing off that as a future project, since it's perfect to use to see what bands are open for your station at any given moment.

If you've never had a go, you should. I've documented how my monitor station works and you can find it on the projects page on my website at vk6flab.com.

WSPR is a really nice way to get into many different aspects of our hobby and the barrier to entry is your imagination.

I'm Onno VK6FLAB

As radio amateurs we learn which frequencies we're allowed to transmit on, where stuff lives and who has priority when there's a signal on the frequency you're operating on and when you need to contact your regulator if you hear an illegal station on the air.

Some of that information arrives in your brain by way of the education process that eventually becomes your license after a test. Depending on which country your license is valid, determines which region of the International Amateur Radio Union your activities fall.

Here in Australia, I'm part of the IARU Region 3, together with the rest of the Asia - Pacific region. In the Americas you're part of Region 2 and Europe, Africa, the Middle East and Northern Asia fall into Region 1. As amateur population sizes go, Region 2 and 3 each cover about 40% of all radio amateurs. Region 1 is about 20%.

Each of these IARU regions has a specific band-plan that is updated regularly as member countries adapt and negotiate different frequencies for different users. The band-edges might not change that often, but bands come and go, segments are added and removed as needs change. For example, here in Australia or VK, the 6m band has been changing because analogue TV has been changing.

Information about band-plans is not easy to come by. For example if I look at IARU Region 2, their documentation is pretty sparse. I've never managed to actually load their website and by the looks of it, neither has the Internet Archive. Given that Region 2 is all of the Americas and represents pretty much two fifths of all amateurs on planet Earth, that's a big hole.

There is some availability in Region 1 and 3, but those too leave to be desired. There does not appear to be any formal method of archiving or naming and the transient nature of the Internet all but guarantees that historic information like this is being lost at a high rate.

Even with those limitations in mind, there is plenty of information to be found. Let's look at Australia, for no other reason than that I was able to pull some of the historic information out of the bit-bucket.

You might be surprised to learn that there is much more change under the hood that far exceeds the band edges and segment changes. The Wireless Institute of Australia publishes the Australian Amateur Band Plan. Using the Internet Archive I was able to count that between November 2007 and November 2019 there were at least 25 different versions of that band plan published, for example in 2008 alone there were at least five different versions.

I managed to download 11 of those band plans which show the introduction of the 2200 meter band, the 630 meter band, changes to mode frequencies, DX frequencies, the allocation of emergency frequencies, changes to FM bandwidth from 6 kHz to 8 kHz on bands below 10m, the formalisation of WSPR frequencies, JT65, FT8 and JT9.

Now I must point out that the information I'm presenting here is incomplete. There are many more changes, just in VK alone. I'm relying on the Internet Archive which only sampled the WIA website 162 times between March 2008 and January 2020. Within those pages there were only 11 copies of the actual band plan and I've only compared three of them, August 2009, March 2015 and October 2019, and of those only a few changes that stood out.

And this is for Australia alone. This is on the HF bands. I've not even looked at the veritable feast of changes associated with the VHF and UHF bands, let alone the cm, mm and higher bands.

Even with this massive disclaimer, my point should be pretty clear. A band-plan is a living document. It changes regularly. Likely much more often than you realise.

I'll leave you with one burning question.

When was the last time you got yourself a copy of the band-plan? Seriously, when was it?

I'm Onno VK6FLAB

Ingenuity is the name of the game in Amateur Radio, building, inventing, solving and helping are all part and parcel of this hobby. We like to lay claim to being the source of all that is good in the world, all that was invented came from Amateur Radio first, right?

Seriously though, sometimes we pick up a technology along the way from other places.

If you've ever picked up your microphone and pushed one or more buttons on it whilst the push to talk button was down, you've likely used this technology that's set out in an ITU recommendation called Q.23. It has the quaint title of: "Technical Features of Push-Button Telephone Sets". It's a brief document as such, all of four pages, two title pages and one mostly dealing with why this Push-Button idea is a great one and how it relates to international phone calls etc.

The meat is in the final page, showing eight frequencies and how you combine them to generate voice frequency signals.

If you've been paying attention, you might recognise this as DTMF or Dual Tone Multiple Frequency signalling.

It's pretty nifty. Send two discrete frequencies at the same time across some link and decode it at the other end. It's nifty because these frequencies might happen during a normal conversation, but not at the same time for a particular duration.

As Amateurs we use this to communicate with our repeaters, to send signals to it, to activate links, to power on and off stuff and all manner of other interesting things.

So, how does it actually work?

Well, you have two sets of four non-overlapping frequencies which you can combine into 16 different combinations, enough for 10 digits, four letters and two symbols. To make this work, the frequencies must be pretty stable, the ITU recommends less than 1.8% off the nominal frequency and distortion must be 20 dB below the fundamental frequencies.

Today producing such a thing is trivial, a chip for a dollar will do the job and another one at the other end to decode it. Four bucks and you're good to go for two-way DTMF at both ends. Bargain.

Being the curios type I went looking to find out what a DTMF circuit might look like before we could buy such products. The closest I came was a build-your-own voice mail system in BYTE! magazine of April 1982 using LM567 tone decoders, but a quick look at the box shows that these are also something that we'd call an Integrated Circuit.

I'm going out on a limb here, since DTMF has been around since it was first supplied to customers in 1963 and suggest that the original DTMF decoders were not quite as trivial as a dollar chip. They likely contained many discrete components including eight separate filters and ways to combine them so signals could be added to each other to detect the existence or absence of a specific tone, but I've yet to actually lay eyes on anything more fundamental than the tone decoders.

That being said, you can connect your all-in-one dollar chip, the CM-8870, to something like an Arduino and do your own decoding of DTMF signals.

Seems that the 1982 BYTE! magazine article was just the beginning of the revitalisation of DTMF, robot controllers, home automation, in-vehicle signalling and more, not to mention, using it to activate IRLP and other wonderful radio services.

Before you start sending me email about this non-Amateur invention, I'll point out that Amateurs also didn't invent copper wire, that was two Scots, or was it Dutch, I forget, fighting over a coin.

I'm Onno VK6FLAB

Over the past six years or so I've single mindedly been producing a weekly segment about Amateur Radio. Over time this has evolved into a podcast which gets about half a million hits a year. Naturally I receive emails and I do my best to respond in a timely fashion.

One of the other things I do is announce a new edition of the podcast on several different sites where listeners have the opportunity to share their views about what ever is on their mind. Sometimes their response is even about the podcast itself, though I confess that some comments appear to indicate that listening isn't part of a requirement to actually form an opinion about what it is that I have said that week.

All that aside, I find it immensely fascinating that the responses I receive vary so much in perspective. It's not hard to understand and observe that our community comes from people along all walks of life. From nine-year olds to ninety-year olds and everything in between.

I tend not to comment directly on such feedback, since everyone has their own opinion, but I came across one post recently that made me sad about the spirit of some Amateurs. In a seemingly bygone era there was a sense that Amateurs would help new people join the community and help them find their way into this vast range of discovery. A place where no question was wrong, where shared experiences are cherished and where the lack of knowledge was an opportunity for learning.

It seems that the moniker that we carry, that of HAM, supposedly because when compared to Professional Telegraphers, we were considered HAM-fisted, went on to form the basis of a proud tradition of experimentation and renewal. Across the globe we see a refresh of the license conditions on a regular basis. We saw that here in Australia with the introduction of the so-called Z-call and K-call, looked down upon by Real Amateurs who had a much more stringent licensing regime.

We discontinued Morse Code as a requirement for an Amateur License as part of a global treaty agreement in 2003. In Australia this meant that from the 1st of January 2004, Morse Code was no longer required if you wanted to obtain an Amateur License. As you know, that didn't signal the end of Morse, just that it wasn't legally required any more. I'm one of many Amateurs learning Morse because I want to, not because I have to. I'd also point out that it was discontinued by global agreement, not two random guys in Canberra.

Back to my point about the spirit of this hobby. The point that was being made is that the Foundation Class license isn't a real license and that it is just being handed to anyone who asks, not like their requirements for Morse Code and a written exam, rather than a multiple-choice test. Essentially conveying that my undignified license and that of my fellow Foundation Licensees isn't to be confused with the noble one that a Real Amateur holds.

This kind of response saddens me and frankly I hear it too often. It's as-if we as a community still have not learned that the world moves on. Technology, in many ways the basis of Amateur Radio, evolves.

For example, in the current requirements for an Amateur License there is a long-winded discussion about the impacts of spurious transmissions on Analogue Television. In Australia, the last Analogue TV broadcast happened on the 4th of December 2013, that's years ago, but it's still required reading on the Amateur License Syllabus.

Similarly we learn about Valves, but attempting to actually obtain such a device is nigh-on impossible. Should we still be learning about those aspects of Electronics, or should we move on?

Amateurs are an inventive lot, we make up new modes, link up new technologies, experiment with all manner of stuff and sometimes we end up with something new, like IRLP, AllStar, SDR, Digital Modes and the like. All because someone got curious, couldn't help themselves and started to fiddle.

As things fall off the radar at one end, Analogue TV, Morse Code, Valves, the other end picks up things, JT65, Digital TV, Lithium Polymer Batteries and whatever else comes around the corner.

So, I'm sad that there are people who feel that my license isn't a real one. As many of my peers, I have a piece of paper from my regulator that begs to differ and a community of enthusiastic eager people who are attempting to find their home among our hobby as it evolves into the future.

Last week I talked about the death of our hobby and that it was vastly mis-represented. As I said, year-on-year, more and more Amateurs join, but overall the numbers decline. I think that opinions expressed about the lack of real licensing, decrying the death of Morse etc. is a symptom of why it is that we have a retention problem in our hobby.

Everyone is entitled to an opinion, but that doesn't mean I have to agree. This is my hobby too and disdain is my fuel!

I'm Onno VK6FLAB

If you've ever been in the market for a new radio, and truth be told, who isn't, you'll find yourself faced with a bewildering array of options varying from obvious to obscure and everything in between. At the obvious end of the scale are things like price, bands and transmit power and at the other end are things like Narrow Spaced Dynamic Range, which you'll find explained by Rob NC0B on his sherweng.com website where he's been publishing receiver test data for many decades.

One of the more subtle options you'll need to consider are handheld, mobile or base radio.

This is harder than you might think, since radios are increasing in functionality every time you wake up and if you look long enough, you'll discover that they're getting smaller at the same rate. Once upon a time you could just look at the size of a radio and define it as belonging in one or other category, but that's no longer a useful distinction. For example, my PlutoSDR is a tiny device, fits in my pocket, but there's no way I'd consider it a handheld, or even a mobile radio.

You might think that a bigger box has more stuff inside, costs more and performs better.

For example, the Drake R-4C receiver and companion T-4XC transmitter require external power and were once rated by the ARRL as very good. In reality the Drake R-4C performed terribly in a CW contest, incidentally, that was what caused Rob to start testing radios in 1976. That receiver and transmitter manage to cover 80m, 40m, 20m, 15m and 10m and together weigh in at 14.3 kg. They're considered a base radio.

The Yaesu FT-817, runs on batteries, weighs in at just over a kilogram and can be carried with a shoulder strap. It comes as a single device and covers many more bands than the Drake transmitter and receiver do, it would be considered a mobile or even portable radio. Obviously it would be hard to jam a Drake into your car or strap it to your belt, but does that mean that you cannot use an FT-817 as the base radio in your shack?

In case you're curious, the slightly beefier brother to the FT-817, the mobile FT-857d, is sitting on my desk as my current base radio. Has been for years.

So why do manufacturers continue to make this distinction between handheld, mobile and base radio? One look at the nearest radio catalogue will tell you that it's not based on either performance or price, not even close. You can buy a handheld with more functionality for the same price as a mobile radio and that same is true when you compare a mobile radio to a base radio.

Radios vary in price from $20 to $20,000. A cynical person would suggest that pricing is based around extracting the most money from your pocket, but a more charitable explanation might be that physical size dictates things like the number of buttons you can fit on a radio, how many connectors can be accessed before the radio flies off the desk from the weight of the coax hanging off the box, how big is the display and other such limitations.

I'm not being glib when I use the word charitable, since much of modern transceiver design revolves around software which can pretty much fit in any box. Using external computers, neither buttons nor a display are needed, leaving external connectors, which if we're being really honest could all fit in a box that would fit in your pocket.

At this point you might wonder if handheld, mobile or base has any meaning at all. As I said, in most cases it doesn't. There's really only one place left where this matters, and that's when you have access to strictly limited space and power if you need to put the radio in your pocket or cram it into your car.

For your home shack, the distinction is unhelpful for most, if not all, amateurs.

Don't believe me? The Yaesu FT-710 currently ranks fourth on Rob's Sherwood Engineering Receiver Test Data List. It's a quarter the size of the top radio and it's sold as a "Base/Portable Transceiver". Yaesu calls it "Compact". It might not fit in the dashboard of my car, but it will fit on the folding table we use during field days.

That isn't an exception either. The Elecraft KX3 is the smallest radio on the first page of Rob's Receiver Test Data list. It fits in your pocket.

Before you start collecting statistics for each radio, I should point out that the more you know about this hobby, the harder this process becomes, so be careful. That said, if you have a massive list of anything to choose from, a new amateur radio, pet food, car, what to have for dinner, whatever, here's a process that will guarantee a result.

It works by eliminating one item at a time until you're left with your preference.

To start, grab the first two items on your list and pick the best one between the two. Ignore everything else, just those two items. You're going to fret about the definition of "best", but don't worry, since every time you do this, you'll have a different idea. All you're doing is saying, all things being equal, between these two options, which one do I prefer. No need to describe why, just pick one. In picking one, you've removed one option from the list.

Now, compare the winner to the next item on the list, again, ignore everything else and pick one and remove the other. Keep doing this until you run out of items. You'll end up with the single option that wins, for whatever reason, from the entire list.

Now, about that radio. All I need is the next paid project.

I'm Onno VK6FLAB

The day came to pass when all my set-up and configuration was going to culminate in the moment of truth when I enabled TX on my WSPR mode station. Before I tell you of my experience, I should give you a little bit of background.

A few weeks ago I managed to erect a HF vertical at my home or QTH. That in and of itself was news worthy, well at least to me it was, since it was the first time since I became licensed in 2010 that I had actual real all-band HF capability at home. Last weekend I ran some RG6, yes, 72 Ohm Quad Shield, low-loss coaxial cable, from my antenna, through the roof, into my shack.

I was thrilled.

Immediately set about getting my HF station up and running. This involved installing WSJT-X, a tool that allows you to do weak signal work, perfect for when you're a low power or QRP station like me. I've previously reported using WSPR, Weak Signal Propagation Reporter on a Raspberry Pi and a dongle, but this time I was using my Yaesu FT-857d.

Reports were coming in thick and fast. Managed to hear stations on all the bands I'm allowed on, 80m, 40m, 15m, 10m, 2m and 70cm. Managed to make it report online and update the various maps around the place.

Brilliant!

Now I wanted to do the next thing. Transmit and see who could hear me and how far my beautiful callsign might travel on 5 Watts.

So, after some abortive attempts, I configured the levels correctly, made sure that my antenna coupler, an SG-237, was tuned and hit "Enable TX" on the screen of my computer.

Dutifully my computer did what was expected, turned on the transmitter and happily made the fan run on my radio for two minutes at a time. I tried 80m, 40m and 15m. All worked swimmingly.

Then I looked on the map to see who had heard me.

Nobody. Nothing. Nada. Niets en niemand.

I could hear N8VIM using 5 Watts, 18649 km away, but nobody could hear me, not even the station VK6CQ who is 9 km from me.

So, what's going on?

Turns out that I'm not using a "standard" callsign. That's right, my VK6FLAB, authorised by the World Radiocommunication Conference 2003, implemented by the Australian regulator, the ACMA in 2005 and issued to me in 2010 isn't a standard callsign.

Seems that the deal-breaker is the four letter suffix, FLAB, that's killing my attempts at making contact.

Now I know that there are moves under way, not quite sure what stage they're at, to allow Australian amateurs to apply for any three-letter suffix and keep that regardless of their license level, but that to me doesn't really solve the underlying issue, where a perfectly legal callsign isn't allowed to be used by one of the most popular modes today.

I've lodged a bug report on the WSJT-X mailing list, but to accommodate this callsign will probably require a fundamental change in the way the WSPR mode and likely several other JT modes will work, not to mention the databases, the maps, API calls and other fun things like logging.

Technically I could have figured this out back in September 2019 when I was first allowed to use digital modes with my license, but I didn't have an antenna then.

In case you're wondering. I also investigated using a so-called extended, or type-2 message, but that allows for an add-on prefix that can be up to three alphanumeric characters or an add-on suffix that can be a single letter or one or two digits.

I could use something like VK6FLA/B, but I'm sure that the owner of VK6FLA would be upset and using VK6/F0LAB might have a French amateur yell Merde! at me when they spot their callsign being transmitted from VK6.

One suggestion was to upgrade my license.

What's the fun in that?

I'm Onno VK6FLAB

Training is a word that is steeped in tradition, it conjures up images of classrooms, teachers, chewing gum stuck to the bottom of your desk and being called upon to attend the front of the class to explain something based on the misapprehension that you did your homework.

Fortunately this is a hobby and training is something you can do yourself, to yourself, by yourself at your own pace. Of course, you can choose to do it with others, but it's not required as such.

We talk about being prepared for doing stuff, but what do we actually do to make that happen?

I've said many times that I like to do contests. In fact, I'm preparing for one right now. This particular contest awards points for making a contact and doubles the points, a so-called multiplier, every time I work a different area.

So, what does my training for this look like, what preparation have I done and what am I doing right now?

My first step was to read the rules, the specifics of what is proscribed, what is permitted and what is counted and what isn't. This sets up the training ground, the framework under which I have to operate my station.

My next step was to pull out a map and draw the boundaries of the areas that affected my score, showing those regions that I'd likely be in and likely make contact with. The crucial part for this was to see where the boundaries were, because it's likely that while driving around, having situational awareness will pay a good part of being successful.

Then I looked at the band conditions. I set-up with my multi-band antenna, a multi-tap Outbacker, and set it up on the 4 HF bands that I'm allowed to operate on, 80m, 40m, 15m and 10m. I set out to make a single contact with each, based on another station a couple of kilometres up the road. We both have vertical antennas to increase our chance of success.

Based on that I determined a few things. One, that this particular antenna and my car make for some pretty specific directionality on some bands. Two, that 10m and 15m were working close in, but not 20km away, that 80m sort of worked but that 40m was a winner.

Based on this test I decided that 40m was going to be my frequency band for this contest.

Then I went about getting tools together. I have a laptop for scoring and a power supply that connects to the car for the laptop. I've charged my radio battery, so it will run for a week on 5 Watts, got together pen and paper as a backup, found a USB charger for my phone and will shortly be packing fruit and water for while I'm on the road.

Last night I fuelled up the car, ready for the contest, and this morning I dug out a few spare antennas in case one of my friends is able to come out and play on-air as well.

I've looked at the map closely, did maths on how best to operate, added markers to my map where good operating positions might be found, likely they're completely rubbish, but going there is when I'll find that out.

I've told others what I'm going to do, encouraged others to get on air and play and by the time I start I'll have had a healthy lunch, a hot shower and comfortable clothes to keep me on the road. I've packed a warm coat, and gone through the contest in my mind to see if I can think of other things that I might need.

All this is only the pre-cursor to actually doing the contest. Call it Part 1. Part 2 is the contest and Part 3 is figuring out what worked and what didn't. I'll tell you about that next time we meet.

Training, it can be fun, or it can be traumatic, you decide.

I'm Onno VK6FLAB

The hobby of Amateur Radio is essentially one of experimentation. Within our community we endlessly build things, from amplifiers to Yagis and every letter of the alphabet in between. With every experiment we grow the amateur radio sphere of influence just a little bit.

As our hobby is evolving into Software Defined Radio, or SDR, the homebrew aspect of our community is also changing bit by bit and as a result, homebrew today is just as likely to be based on software as it is in hardware.

Unlike the physical world where you need to source and buy components, design a circuit, build it, test it and then put it in a box, in the software realm you can get started with the computer that is more than likely within reach right now.

Recently I took delivery of a new SDR, an ADALM Pluto. It's essentially a Linux computer, FPGA and transmit capable SDR in a small box. I bought it specifically for the purpose of experimentation.

One of the first things I did with this device was install an existing piece of software called dump1090. The tool listens to 1090 MHz and decodes Mode S transponders, used by aviation to report aircraft information in real-time.

Originally written by Salvatore Sanfilippo in 2012 for the RTL-SDR dongle, it was patched by several people and in 2017 it was updated by Jiang Wei to support the Pluto SDR. My contribution to the project is minor. I've updated the on-board web-server to use Open Street Map and a few other cosmetic changes.

For me it was a "Hello World" project, something that's the software equivalent of warming up your soldering iron and pre-tinning the wire you're about to use.

The tools to do this is what I want to discuss.

When you look at the software that underlies much of the SDR world, the digital modes, logging, contesting, even the software inside tools like the Nano-VNA, much of it is open source. That means that as a curious amateur you can have access to the underlying equivalent of the circuit diagram. As you can with a soldering iron, a scribe and wire, you can patch or update a circuit. In the software realm you can do the same once you have access to the source code.

The tools you're going to get in touch with are text editors, compilers, libraries and configuration files. If that's not your thing, I appreciate that, but if it sparks your interest, you'll open the door into a brand new world of software development where you can determine how a mode works or what it supports or how it interacts with your radio or testing gear.

When you jump in, likely feet first, you're going to make mistakes and lose hair and sleep and you'll be shaking your virtual or physical fist at the person who came before you, but then that's the world of experimentation, so likely you'll already have that down pat.

You'll likely play with different tools that require different versions, often installed side-by-side, much to your chagrin when you learn that it just won't work. Not to mention that removal of the offending tool often leaves interfering cruft behind, not unlike unsightly and short-circuiting blobs of solder.

I'm here to introduce you, albeit briefly, to a tool that will take much of that pain away. The free tool is called Docker. It has got little in the way of visibility in the amateur radio world, but in the software development world it's pretty much old hat.

Essentially the idea is that you can install stuff into a so called disposable container so you can have your copy of dump1090 installed in one container and your copy of codec2 in another, a copy of rtl-sdr in a third container, all working independently from each other, without needing to complicate things with multiple computers or virtual machines. If a developer uses Debian, another uses Ubuntu and a third uses Red Hat, you can run these side-by-side without any issue. If they need an ancient version of something, that too is handled without a problem. Make a mistake, destroy the container and start again, fresh.

Docker is a tool that allows you to build an environment on Linux, MacOS and Windows, as well as the Raspberry Pi, that acts and behaves in many ways like a virtual machine. In all the ways that you're likely to use it, at least initially, it's indistinguishable. What that means is that the operating system, the compiler and the libraries that you need for one tool won't affect those needed for another tool.

The best part of this is that you can build on a massive library of pre-existing Docker containers and use files that describe how to build and compile tools like dump1090.

If you look for my callsign vk6flab on github.com, you'll find my version of dump1090 and you'll find a Dockerfile that describes how I built it. The project contains all the bits you'll need to get started with your own version of dump1090, or some other project that tickles your fancy.

Every time you build something, the amateur radio sphere of influence grows just that little bit.

I'm Onno VK6FLAB

One of the many questions that new amateurs ask is, "When should I get on-air, and on what band?" The often-heard reply is just to get on-air and make some noise. As time goes by, the importance of this seems to fade in favour of using HF prediction tools. Some amateurs never venture beyond that point, relying almost exclusively on technology to determine if they should turn on their radio or not.

If you search the internet for "current HF conditions", you'll end up with dozens of sites boldly claiming to provide precisely that information, some even using the label "Real-Time". You'll find instructions from countless self-proclaimed "experts" on how to read propagation conditions from their favourite site. There's even widgets that you can install on your website displaying propagation data per amateur band with helpful labels like "Band Closed" or showing conditions as "Poor", "Fair" or "Good". Some of these widgets even include an embedded time-stamp to prove just how "current" the information is.

If that's how you decide to activate your amateur station, like I once did, I have some questions.

Where is this information coming from, is it accurate, and when was it last updated?

To give you an idea of just how complex this question is, consider visiting two popular websites, solarham.net from Canada and spaceweatherlive.com from Belgium. On their home-pages, you'll find all manner of numbers, charts, photos, events, notifications, alerts, and warnings, each related in some way to HF propagation and the condition of the Sun.

Sounds great, excellent resources, job done.

Well, no.

Let's start simple. Location.

Leaving aside where the site's owner is or where the servers are, both potential sources of confusion, consider where you are and where the remote station is that you're trying to contact. Now compare that with the propagation data location. Do you know where the measurements came from and if they're relevant to you?

What about data currency?

For example, if you can see the Sun, you can count the number of sunspots since that data comes from physically looking at the Sun. Mind you, can someone count the number of sunspots at night? It's not a trick question. The Sun isn't overhead for everyone all the time, and the data from any particular observer will be out of date at night. When was the count updated? Is it still actually current, let alone real-time? Obviously, not everyone uses the same data source either.

In case you're wondering, why are we counting by eye in the space age? It turns out that, since Galileo more than 400 years ago, it's the most long-term, reliable way to keep data consistent between observers and instruments, both of which often last only one or a few solar cycles, and it's also cheap!

What about equipment changes and failures in data gathering?

Geomagnetic activity isn't global; it's measured using a device called a flux-gate magnetometer. Measurements from specific instruments scattered around the globe are combined into the planetary, or Kp index. You'll discover that locations used change over time, and when instruments are down, the numbers are estimated, but you won't see that unless you actually find and explore the source data.

It's not just solarham.net and spaceweatherlive.com; it's pretty much every single site that shows any form of HF propagation or space weather information. Even sites based in a specific country, like the Australian Space Weather Service, have many instruments scattered around Australia. If you happen to be near an actual instrument, where "near" is anything less than 500 km away, how do you know if that instrument was actually online when a measurement was made?

Even if the instrument near you is working, is the data relevant to the receiving station on the other side of the planet?

If you look closely at the sites giving out current HF conditions, you'll discover that most of these don't even tell you where the data comes from, let alone if any of it was estimated to come up with their current reported values or recommendations.

If you start searching for historical information, this problem gets bigger. You'll find many sites that claim to have data, but are invariably underfunded, are rife with broken links, out-of-date servers, and moved, deleted, and abandoned pages. If you unearth a dataset, you'll discover that everyone uses a different standard to record their measurements.

How do you even know if combined measurements are coming from the right column? Think I'm kidding? There are documents with warnings about different formats, calculations, and dates on which these changed. Aggregating this data is challenging, at best.

So, is there a better way?

Yup. You're not going to like it. "Get on-air and make noise!"

I can hear you groaning from here. It's not all bad. You can run your own beacon to see the conditions at your location. It's what started me down the path of installing a WSPR, or Weak Signal Propagation Reporter, beacon and leaving it running 24/7. Currently, I'm focused on very weak, 10 mW signals. So far, it's been reported 3,685 km away.

If you visit the VOACAP or Voice of America Coverage Analysis Program website, you'll find a visualisation of how FT8 propagation worked between ITU zones between 2017 and 2019. It's not current, but it's an excellent way to see how propagation data can be derived from actual contacts.

What we really need are more beacon transmitters and online receivers.

I'm Onno VK6FLAB.

Amateur radio is a living anachronism. We have this heady mix of ancient and bleeding edge, never more evident than in a digital mode called Automatic Packet Reporting System or APRS. It's an amateur mode that's used all over the place to exchange messages like GPS coordinates, radio balloon and vehicle tracking data, battery voltages, weather station telemetry, text, bulletins and increasingly other information as part of the expanding universe of the Internet Of Things.

There are mechanisms for message priority, point-to-point messages, announcements and when internet connected computers are involved, solutions for mapping, email and other integrations. The International Space Station has an APRS repeater on-board. You'll also find disaster management like fire fighting, earthquake and propagation reporting uses for APRS. There's tools like an SMS gateway that allows you to send SMS via APRS if you're out of mobile range. There's software around that allows you to post to Twitter from APRS. You can even generate APRS packets using your mobile phone.

In my radio travels I'd come across the aprs.fi website many times. It's a place that shows you various devices on the APRS network. You can see vehicles as they move around, radio repeater information, weather, even historic charts of messages, so you can see temperatures over time, or battery voltage, or solar power generation, or whatever the specific APRS device is sending.

As part of my exploration into all things new and exciting I thought I'd start a new adventure with attempting to listen to the APRS repeater on the International Space Station. I'm interested in decoding APRS packets. Seeing what's inside them and what kinds of messages I can hear in my shack. Specifically for the experiment at hand I wanted to hear what the ISS had to say.

After testing some recommended tools and after considerable time hunting I stumbled on multimon-ng. I should mention that it started life as multimon by Tom HB9JNX, which he wrote in 1996. In 2012 Elias Oenal wanted to use multimon to decode from his new RTL-SDR dongle and in the end he patched and brought the code into this century and multimon-ng was born. It's available on Linux, MacOS and Windows and it's under active development.

It's a single command-line tool that takes an audio input and produces a text output and it's a great way to see what's happening under the hood which is precisely what I want when I'm attempting to learn something new.

In this case, my computer was already configured with a radio. I can record what the radio receives from the computer microphone and I can play audio to the radio via the computer speaker. My magical tool, multimon-ng has the ability to record audio and decode it using a whole raft of in-built decoders. For my test I wanted to use the APRS decoder, cunningly disguised as an AFSK1200 de-modulator. I'll get to that in a moment.

The actual process is as simple as tuning your radio in FM mode to the local APRS frequency and telling multimon-ng to listen. Every minute or so you'll see an APRS packet or six turn up on your screen.

The process for the ISS is only slightly different in that the APRS frequency is affected by Doppler shift, so I used gpredict to change the frequency as required; multimon-ng continued to happily decode the audio signal.

I said that I'd get back to AFSK1200. The 1200 represents the speed, 1200 Baud. The AFSK represents Audio Frequency Shift Keying and it's a way to encode digital information by changing the frequency of an audio signal. One way to think of that is having two different tones, one representing a binary zero, the other representing a binary one. Play them over a loud-speaker and you have AFSK. Do that at 1200 Baud and you have AFSK1200.

When you do listen to AFSK and you know what a dial-up modem sounds like, it will come as no surprise that they use the same technique to encode digital information. Might have to dig up an old dial-up modem and hook it up to my radio one of these days.

Speaking of ancient. The hero of our story, APRS, dates back to the early days of microcomputers. The era of the first two computers in my life, the Apple II and the Commodore VIC-20. Bob WB4APR implemented the first ancestor of APRS on an Apple II in 1982. Then in 1984 he used a VIC-20 to report the position and status of horses in a 160km radius using APRS.

As for the International Space Station, the APRS repeater is currently switched off in favour of the cross-band voice repeater, so I'll have to wait a little longer to decode something from space.

I'm Onno VK6FLAB

Over the past week I've been attempting to work out what the IARU, the International Amateur Radio Union, actually does and how it works. I started looking into this because the IARU is this year celebrating a century since its foundation in 1925. You might think of the IARU as one organisation, but behind the scenes there are actually four, one for each so-called "Region" as well a Global organisation called the International Secretariat, headquartered at the ARRL in Connecticut.

The Regions have been negotiated by members of the ITU, the International Telecommunications Union. As early as 1927 the ITU documented differences in frequency allocations between Europe and Other Regions. In Cairo in 1938 it defined boundaries for Europe. In Atlantic City in 1947, the ITU defined three Regions, with specific boundaries, essentially, Europe and Africa, the Americas and the rest of the world.

As a surprise to nobody, this is purely a political decision, especially since radio waves don't get to have a passport and pass border control. The impact of this continues today, generations later. We still have this patchwork of frequency allocations, we still have exclusions, different band-edges and other anachronisms.

The Regions are further divided into Zones. When you start looking at the ITU zone map in detail it gets weird. For example, Iraq is in Region 1, neighbouring Iran has been specifically excluded from Region 1 and moved to Region 3. In case you're curious, Iran has been represented at the ITU since 1938.

Antarctica is part of seven of the 90 ITU zones and all three Regions, because of course it is.

Zone 90, jammed between zones 35, 45, 61, 64, 65 and 76, almost as an afterthought, contains one landmass, Minamitorishima, an island that sticks 9 m above the water, has a 6 km coastline and is generally off-limits to the general public. The nearest land in any direction is over 1,000 km away. It's got an IOTA, Islands On The Air, designation, OC-073 and despite its isolation, has been activated by radio amateurs using JD1 prefix callsigns.

I live in Australia, ITU zone 58, part of Region 3, together with the two most populous countries on the planet, India and China and the rest of eastern Asia, but not the Former Soviet republics and most, but not all of Oceania, you know, because .. logic. From a population perspective Region 3 is the largest by several orders of magnitude, but you'd never know it if you went looking.

Why am I telling you all this?

Well, that's the international stage on which the IARU is representing amateur radio. In 1927 the underlying assumption was that each service, Amateur Radio included, had a global exclusive allocation. The reality was different. Spectrum was in such short supply that individual exceptions were carved out, which as I've said resulted in splitting up the world into regions, starting in 1938 and codified in 1947.

The IARU in 1925 is a different organisation from what it is today. In 1925 individual amateurs could become members. As soon as enough members from a country joined, they'd be grouped together. When there were enough groups, the IARU became a federation of national associations.

Over time, the IARU as a single body, evolved into the structure we have today. In 1950 in Paris, the IARU Region 1 organisation was formed. In 1964 in Mexico City, IARU Region 2 was created and in 1968 in Sydney, IARU Region 3 came to exist. You can see their online presence at the various iaru.org websites.

How it works is no clearer now than it was when I started. What it has achieved is equally unclear. I'm currently trolling through ITU World Radiocommunications Conference documentation going back to 1903 to discover references to Amateur Radio, but it's hard going. At least it's something. The IARU documentation is not nearly as extensive or up to date.

It appears that many, if not all, of the people working behind the scenes at the various IARU organisations are volunteers. If you feel inclined, there is an ongoing request for assistance, and before you ask, yes, I looked into helping out, but that will have to wait until funds permit.

If you have insights into the functioning of the IARU, don't be shy, get in touch. cq@vk6flab.com is my address.

I'm Onno VK6FLAB

Recently I managed to get some quality on-air time when I participated in a contest. This isn't about contesting. Although I suppose tangentially it is. It was a most enjoyable experience shared with some friends and because we did it at a local radio club, Sunday morning had all manner of visitors joining us for a little social chat, just the ticket for breaking the monotony of calling CQ.

Normally when I do a contest I wear headphones, actually it's a headset, that is something over my ears with an attached microphone to capture my contacts without me having to use my hands or move my head towards a fixed location while I'm making the contact.

One hour in my trusty headset broke clean in half. They've been with me since 2012 so I was a little disappointed. They weren't cheap. I'm not going to tell you what brand it is, but they're very popular in the contesting community and I bought them based on those recommendations.

Given that I now had no headset I immediately went to the nearest social media outlet to ask for recommendations on what to do next and the typical responses included different brands, ways of repairing, better models, those kinds of things. Everything you'd expect from a community which has some experience in creating a headset that actually works within the context of amateur radio.

Don't get me wrong some of these suggestions were great but I don't particularly fancy spending $500 on a headset that is suited to listen to glorious HF SSB. If you're not familiar, think long distance AM radio playing music you can barely hear hosted by a DJ you can almost make out. Making a contact using HF SSB is really an exercise in deciphering really bad audio, often with lots of people on the same frequency at the same time, all vying for your attention. Making a contact, a QSO, in that kind of pile-up can be a challenge.

The contest ran for 48 hours so in my down time I had to come up with a solution since making a repair within the time available seemed unrealistic, even though I happened to have spare parts somewhere in my shack. As an emergency standby I brought along my mobile phone in-ear headphones.

They're lightweight, cheap, and they block out the audio from nearby conversations in the shack. Everything you want in a contesting headphone. I used a microphone on a boom, attached to the desk, but that wasn't ideal, moving your head, looking at the logging screen, operating the radio, from a user interface perspective, it left me wanting.

I should add that I prefer to operate a contest using Voice Operated Control, or VOX, that is, setting up your radio in such a way that you don't need to push any buttons to talk, you open your mouth and the radio automatically starts transmitting. Very helpful when you have your hands on the keyboard and the foot-pedal is just out of reach or making your leg tired because you have to hold it up so you don't accidentally key up the transmitter.

It occurred to me that I'd never seen this particular use of a headphone in the context of amateur radio. After the contest I went out to find a similarly spartan microphone. I'm still weighing up the options but I think I might have settled on the idea of pursuing headphones and microphones intended for use on a mobile phone, precisely because they are designed to deal with blocking out surrounding audio from both the earpiece and the microphone.

As I'm describing this to you it occurs to me that it doesn't even need to be wired, a simple Bluetooth audio module plugged into the radio with wireless mobile phone headsets might just be the ticket.

What has been your recipe for success in creating an environment where you can hear a HF SSB QSO in a contest environment without spending half the value of the radio?

I'm Onno VK6FLAB

With computers becoming more and more ensconced within the confines of our radio shack the variety of information available is increasing regularly. The introduction of a waterfall display has dramatically simplified the process of detecting what the activity level is on a particular band.

If you've never seen a waterfall display, it's often a real-time, or nearly real-time display of radio activity. Leaving aside the mechanics of how this comes about, or how much you see, generally it's presented as a picture that changes over time.

In reality it's a very compact way of showing a lot of information.

You can think of it as a chart, showing the horizontal axis as frequency, the vertical axis as time and the colour as signal strength. So as you look from left to right you'll look at higher and higher frequencies. For example, the left side might be 7 MHz and the right side might be 7.3 MHz. Halfway along is 7.150 MHz.

Similarly, now, as in zero seconds ago is at the top of the chart and 1 minute ago is lower. Depending on how fast you've set it to update the whole screen might represent 10 seconds, 10 minutes or 10 hours of information, entirely flexible, entirely configurable, entirely arbitrary.

If you think of the colour black as having no signal strength and the colour red being maximum signal strength, then the brighter the colours, the more signal there is.

A morse code signal might turn up as a series of dits and dahs running down the screen, with the oldest one being at the bottom and the newest one at the top.

An AM signal might show up as a thick line with a bright colour, that's a high signal strength in the middle and lighter colours or low signal strength towards the edges.

Every mode has its own visual characteristic and there are even modes that allow you to read information within a waterfall display.

One of the other things you'll see in a waterfall display is strange artefacts, things like a diagonal line for example.

If you think of what a diagonal line represents as a radio signal, it's something that has a strong signal at a particular time and frequency. A moment later it's changed frequency and a moment later it's done it again. The steepness of the line is dependent on two things, the speed that the frequency changes and the speed that the waterfall is updating.

Before waterfall displays, the way you'd experience such a signal would be something that flashes up as a low to high swoop, or a high to low swoop, depending on your listening mode and the direction of the frequency change.

So what is that signal?

Well, it's likely to be something called an Ionospheric Sounder. It does what you think it does. Ping the ionosphere across multiple frequencies. The station doing this is listening for a return echo to see if the ionosphere is reflective for that particular frequency at that particular moment. The information can be used to create a map of what the ionosphere is doing right now, which in turn is used to figure out what frequency to use to make a contact.

I should also mention that there is a signal identification wiki which shows and plays various identified and unidentified radio signals, hours of fun for the family.

I'm Onno VK6FLAB

The activity of amateur radio revolves around experimentation. For over a century the amateur community has designed, sourced, scrounged and built experiments. Big or small, working or not, each of these is an expression of creativity, problem solving and experimentation.

For most of the century that activity was accompanied by the heady smell of solder smoke. It still makes an appearance in many shacks and field stations today, even my own, coaxed by an unsteady hand, more and more light and bigger and bigger magnification, I manage to join bits of wire, attach components and attempt to keep my fingers from getting burnt and solder from landing on the floor.

I've been soldering since I was nine or so. I think it started with a Morse key, a battery and a bicycle light with a wire running between my bedroom and the bedroom of my next door neighbour. In the decades since I've slightly improved my skill, but I have to confess, soldering isn't really my thing.

My thing is computers. It was computers from the day I was introduced in 1983 and nothing much has changed. For reasons I don't yet grasp, I just get what computers are about. They're user friendly, just picky whom they make friends with.

When I joined the amateur community, it was to discover a hobby that was vast beyond my wildest imagination, technical beyond my understanding and it was not computing. Little did I know.

Computing in amateur radio isn't a new thing. For example, packet radio was being experimented with in 1978 by members of the Montreal Amateur Radio Club, after having been granted permission by the Canadian government. In 2010 when I came along we had logging, DX-clusters and the first weak signal modes were already almost a decade old.

Software Defined Radio has an even longer history. The first "digital receiver" came along in 1970 and the first software transceiver was implemented in 1988. The term "software defined radio" itself was 15 years old when I joined the hobby and truth be told, it's a fascinating tale, I'll take a look at that at another time.

When I started my amateur journey like every new licensee, I jumped in the deep end and kept swimming. From buying a radio, to discovering and building antennas, from going mobile to doing contests and putting together my home station, all of it done, one step at a time, one progressive experiment after another, significant to me, but hardly world shattering in the scheme of things.

Now that I've been here for a decade I've come to see that my current experiments, mostly software based, are in exactly the same spirit as the circuit builders and scroungers, except that I'm doing this by flipping bits, changing configurations, writing software and solving problems that bear no relation to selecting the correct combination of capacitance and reactance to insert into a circuit just so.

Instead I'm wrestling with compilers, designing virtual machines, sending packets, debugging serial ports and finding new and innovative ways to excite transceivers.

For example, today I spent most of the day attempting to discover why when I generate a WSPR signal in one program, it cannot be decoded by another. If that sounds familiar, that was what I was doing last week too. This time I went back to basics and found tools inside the source code of WSJT-X and started experimenting. I'm still digging.

As an aside I was asked recently why I want to do this with audio files and the short answer is: Little Steps.

I can play an audio file through my Yaesu FT-857d. I can receive that and decode it. That's where I want to start with my PlutoSDR experiments, so when I'm doing this, I can use the same audio file and know that the information can be decoded and that any failure to do so is related to how I'm transmitting it.

Back to soldering irons and software. In my experience as an amateur it's becoming increasingly clear that they're both the same thing, tools for experimentation, with or without burning your fingers.

I'm Onno VK6FLAB

On Thursday the 20th of April, 2023 at 04:17:56 UTC the world was subjected to a rare event, a hybrid solar eclipse. In Perth I experienced a partial eclipse and people lucky enough to be directly in line, places like Ningaloo Reef, Exmouth and Barrow Island, experienced a total eclipse. Timor-Leste had the experience of the peak total eclipse.

At the time I went into my shack and refreshed the WSPR or Weak Signal Propagation Reporter beacon map I have open and noticed that my beacon wasn't reported. I sagely nodded my head, that makes sense, no Sun, no propagation and I got on with my life.

Last week a fellow amateur, Will VK6UU, asked if anyone had any VK6 specific HF propagation reports to make. Being the data geek that I am, I thought to myself, "Aha! I can do some data analytics on the WSPR dataset that I have." So, the die was cast for a few enjoyable hours of importing 2.4 gigabytes of compressed data into a database and constructing a set of SQL queries to see what I could learn.

Before getting stuck in, I spent a few hours thinking about the problem. How could I go about doing this? Propagation information is notoriously fickle. You have to consider the obvious things like the Solar Index and the Geomagnetic Index which vary considerably. Then there's the nature of the various reports themselves. Not everyone has their beacon on all the time, not everyone has their receiver on all the time. Weekends are more popular than weekdays and popularity overall is growing exponentially. The solar cycle is on the way to its peak, so there's that variation to consider and if that's not enough, how should you compare the Signal To Noise ratio between weak and strong beacons?

With all that in hand I set about constructing a plan. I created a folder to hold my charts and SQL queries, intent on uploading that to GitHub when the work was done.

For my very first test I thought I'd count the number of reports per band in a 24 hour window around the eclipse. I imported all the WSPR records that had a VK6 callsign, either as the transmitter or the receiver, given that I was interested in learning if stations transmitting from VK6 could be heard elsewhere and inversely, could VK6 stations hear any other stations?

As my first effort, I created a scatter-plot to get a sense of what kind of numbers I was looking at. The initial result was interesting. Around the eclipse itself there was no propagation. This wasn't unexpected, since that's what I'd seen on the day at the time on my own map. I changed my data to use a cumulative count per band to see if any band was particularly different and then discovered that there was no propagation at all, on any band.

That seemed ... odd.

So, I had a look at the source data and discovered a gap, which accounted for what my chart was showing. I added a fake record for the eclipse time itself, just so I could see where on the chart this gap was. Turns out that for VK6 stations, the gap is just over five hours, but it's not centred around the eclipse. There's a four hour window before the eclipse and a one hour window after it.

Then I started looking at all the reports from across the world. To give you a sense of scale, across April 2023 the dataset has nearly 139 million rows. It's 12 gigabytes in size. By contrast, in March of 2008 when the first reports started, there were just over 93 thousand reports in a 7 megabyte file. Charting this shows exponential growth, hitting a million reports in July of 2009, 10 million reports in January 2016 and 100 million reports in October of 2021.

So, the eclipse and global propagation. The results came in and the reports are that there was no propagation, on any band at any point during the just under two hours and 12 minutes before the eclipse and the 38 minutes following it.

That ... or the WSPRnet.org database was down during the eclipse.

So, unfortunately I cannot tell you what propagation was like during the eclipse, since it appears that those records don't exist.

Looks like we'll have to wait until 2031 when we can try this again. We'll all be a little older and wiser by that time and perhaps we can come up with a way to ensure that the global central WSPR data server is running without downtime, scaled to match the growing requirements and paid for by a benevolent organisation with deep pockets.

I did start considering making lemonade from my lemons and charting the kinds of down time the WSPR server has, but just looking over the various discussion groups showed that this is going to be painful. On the plus side, I learnt about SUM OVER and LAG functions in SQL, so there's that.

I must confess that if we're going to seriously use WSPR as a propagation analysis tool we need to fix these kinds of issues. I have no doubt that running WSPRnet.org is a massive enterprise and that it costs real time and money to make that happen.

So, who's up for the challenge and will the real owner of WSPRnet.org please raise their hand?

Finally, if by chance you were running a WSPR receiver during the 2023 Solar eclipse you might want to consider looking at sharing your logs, since they're potentially the only record still remaining.

I'm Onno VK6FLAB

The American Radio Relay League or ARRL is one of the oldest amateur associations on Earth. 1926 saw the birth of "the Radio Amateur's Handbook", the first edition of what we now know as "The ARRL Handbook For Radio Communications" featured chapters on what it means to be an amateur, how to build and operate a station, how propagation works and how to experiment. The very first handbook had 5000 copies printed and thanks to the website WorldRadioHistory.com we have access to a signed copy by the author himself, the Communications Manager of the ARRL, Francis Edward Handy (W1BDI). He starts the 228 page book with the following words:

This Handbook is written as a guide for member-operators of the League. It is also useful as a source of information to the man who wants to take part in amateur radio activity but who has no idea of how to get started. Written first of all for the beginner, such an amount of useful and up-to-date information has been added that the Handbook in its present form is equally valuable as a compendium of information for the experienced brass-pounder and the beginner alike.

The first edition doesn't show a cover price, but the third edition, published a year later shows a charge of $1. The 2022, or 99th edition has nearly six times as many pages, 1280 of them, it costs ten times as much per page and sells for nearly 50 times as much at $49.95. The current handbook features topics such as Radio electronics theory and principles, Circuit design and equipment as well as articles and projects that include 3D printing, portable battery selection, safe antenna and tower work practices and comes in a variety of formats including electronic and box sets.

I'm giving this background to give you a sense of how things have evolved in the past century. For example, one thing that the very first edition didn't have was a page called the Amateur's Code. The oldest copy I've found appears in the 1927 or third edition.

If you're familiar with the words, you're in for a treat. If not, sit back and imagine it's 1927, or 1923, more on that in a moment.

The Amateur's Code

I - The Amateur is Gentlemanly. He never knowingly uses the air for his own amusement in such a way as to lessen the pleasure of others. He abides by the pledges given by the A.R.R.L. in his behalf to the public and the Government.

II - The Amateur is Loyal. He owes his amateur radio to the American Radio Relay League, and he offers it his unswerving loyalty.

III - The Amateur is Progressive. He keeps his station abreast of science. It is built well and efficiently. His operating practice is clean and regular.

IV - The Amateur is Friendly. Slow and patient sending when requested, friendly advice and counsel to the beginner, kindly assistance and cooperation for the broadcast listener: these are marks of the amateur spirit.

V - The Amateur is Balanced. Radio is his hobby. He never allows it to interfere with any of the duties he owes to his home, his job, his school or his community.

VI - The Amateur is Patriotic. His knowledge and his station are always ready for the service of his country and his community.

This version is credited to Paul M. Segal 9EEA, Director, Rocky Mountain Division ARRL.

The code appears on page 9 of the 1927 edition of the handbook. It uses Roman numerals to identify each point, the title is beautifully rendered with the Old English Typeface and it's shown inside a rectangle on a page on its own.

Over the next 45 years the text stays the same. There are changes like colons to semi-colons, an additional comma and the evolution from Roman numerals to modern numbers, and then written numbers and finally the removal of the numbers entirely. At one point the title is changed from "Amateur's Code" to "Our Code", but that only lasts for one edition. Speaking of editions, the 1936 edition, the thirteenth in the series, is referred throughout as the 1936 edition, superstition is alive and well.

The credit changes over time as well. In 1929 Paul's callsign is changed from 9EEA to W9EEA.

In 1943 we see a once-off credit appear. It states that the code was written in 1923 by Lieut.-Commander Paul. M. Segal, General Counsel of ARRL. It's the only credit that shows a different year from any of the other references which all point at 1928 as the original year, which is what the ARRL uses today. Interestingly, we have a copy of the handbook from 1927 that features the code, so it's entirely possible that 1923 is actually correct and it's not hard to imagine that a poorly printed 3 looks like the remains of the number 8.

To add to this, there's a 1944 FCC report to the President of the United States of America that contains a reference to "Lieutenant Commander Paul. M. Segal, the radio industry attorney". In addition there's an announcement in the New York Times, dated 25 May 1968 with the headline: "Paul M. Segal Is Dead at 68; Expert in Communications Law"

I don't have access to any version of the Second Edition of the handbook which had two print runs in 1927. It's entirely possible that the code appeared there, but I have no evidence either way. I do believe that Paul M. Segal, 9EEA Director of the Rocky Mountain Division of the ARRL is the same person as Lieutenant Commander Paul. M. Segal, General Counsel of ARRL and radio industry attorney who became a silent key in 1968.

Credits, layout and font changes aside, 1973 sees the first time when the words of the Amateur's Code actually change.

Let me illustrate.

The original first clause reads:

I - The Amateur is Gentlemanly. He never knowingly uses the air for his own amusement in such a way as to lessen the pleasure of others. He abides by the pledges given by the A.R.R.L. in his behalf to the public and the Government.

In 1973 that's changed to:

One The Amateur is considerate . . .He never knowingly uses the air in such a way as to lessen the pleasure of others.

The first four clauses are modified to greater and lesser degree, clause five and six stay the same.

Today the ARRL website shows the first clause as:

The Radio Amateur is CONSIDERATE...He/[She] never knowingly operates in such a way as to lessen the pleasure of others.

And the credit reads: "adapted from the original Amateur's Code, written by Paul M. Segal, W9EEA, in 1928"

It's noteworthy that going back to the original text the very first clause encourages the amateur to be gentlemanly, something which we can relate to in terms of being respectful, polite and civil.

It's also clear that the Amateur's Code is a living document and has been moving with the times. I think that we as a community have the opportunity to participate in another review and I will investigate and share with you some of my thoughts on the matter.

I think that it is important that we have a code of conduct that reflects our values and at present the best starting point we have is the Amateur's Code.

I'm Onno VK6FLAB

Whenever I'm out in the bush in the process of erecting some or other wire contraption, uh, antenna, I cannot help but think of the iconic Australian rock band, Skyhooks, not for their glam rock inspired music, nor for their pure mathematics and computer science degree holding guitarist, but for their name.

In antenna erection, a skyhook is called for when you point at a spot in the sky and will into being an attachment point for the wire antenna in your hand. It's always in the perfect spot, holds any weight and of course it's made from unobtainium.

Absent a skyhook, there are other ways of hoisting an antenna into the air. A recent discussion revealed that in some places catapults and trebuchets are frowned upon, if not outright illegal. Can't imagine why. Depending on their size, they may be difficult to transport.

In the same vein, antenna launchers, lightly camouflaged spud guns, are essentially a gas pressurised tube, causing a projectile to be launched by releasing a valve. Those too are pretty restricted and for good reason.

Fortunately there are plenty of other ways of getting things to be in the right place.

Let's explore.

One option is to bring along a pole, made from whatever is at hand, a multi-element fibreglass pole made by Spiderbeam, mine is 12m long, has always worked for me, though I will confess that I have managed to break one. It did take a 135 degree bend in the tip to achieve that. I'll hasten to add, I didn't set out to do that. Previously it had easily sustained 90 degree abuse in heavy wind. I purchased a new one. I've used it for years. It's not cheap, but it works.

Alternatives, much less strong, are using fishing rods or much less flexible, aluminium tubes, pool cleaning extension poles, even painters poles and at a pinch, lengths of wood screwed together, or if you're a Scout, logs lashed into some contraption.

Then there's using the nearby landscape.

Getting a wire into a tree is an activity that's fun for young and old. Not so much for the person attempting it. Often this starts with throwing things at the tree. You might find a spanner, tie it to a rope and whirl it around, letting go at just the right moment to get it to where you're going. This is not a safe activity and not recommended away from emergency medical assistance, you've been warned.

This graduates to using things like a monkey's fist knot. I was given a brightly coloured one, lovingly hand crafted by Alan VK6PWD. It's reminiscent of a Sea Scout woggle knot. Truth be told, it's too beautiful to use, or rather risk losing. Tie it to a line and whirl and throw. Then there's the arborist throw bag, same deal.

Each of these whirling activities are fraught. Mainly because you need to strike a balance between the strength of the line, strong enough to be chucked, uh, thrown, but weak enough that you can break it if it gets caught and believe me, it will.

There's the option of co-opting your dog's ball launcher. Tie a rope to the ball and hurl. Success depends on how quick your dog is in catching low flying tennis balls.

The last time I went fishing was in 2003 when I used a string and a safety pin to catch an, admittedly, tiny fish at Harry's Hole using a tiny piece of bread, took all of 5 minutes. That said, I have a new fishing rod, well, it was new when I purchased it, but now it's a couple of years old. It was the absolute cheapest one I could find. I also bought a box of sinkers.

Purchased on the advice of Bob VK6POP, I've used that rod many times to launch a sinker at a nearby tree and used it to pull through some line and then an antenna. It's still a balance between using a fishing line that's strong enough to handle the weight of a sinker and weak enough to break when you want to. The sinker needs to be just the right weight too. Too light and you'll launch it at the right branch where it will stay for the rest of the life of the tree. Too heavy and it will end up somewhere in the bush, never to be found. Grey sinkers tend to vanish in the grass, so if you can find it, look for something nice and bright, fluorescent is best. In a pinch you can use a couple of sinkers, like when you've run out, but in my experience they tend to wrap themselves around a branch.

Of course you could also just climb into a tree, or hire a cherry picker, but I'm not that flexible, either in my joints or wallet, so those options don't do it for me.

If you have a friendly arborist nearby, there's no shame in paying them to attach a pulley to the required branch in your backyard. Just make sure that the line you use on the pulley cannot escape the groove and get jammed between the wheel and the cheek, don't ask me how I know.

So, what ways do you use to summon a skyhook and does it include a Siberian jukebox?

I'm Onno VK6FLAB

Antenna testing in the field.

If you've been around amateur radio for any time at all, you'll know that we spend an awful lot of time talking about antennas. How they work, where to get them, how to build them, how strong they are, how cheap they are, how effective, how resonant, you name it, we have a discussion about it.

It might not be immediately obvious why this is the case. An antenna is an antenna, right?

Well ... no.

Just like the infinite variety of cars on the road, the unending choice of mobile phones, ways to cook an egg and clothes to wear to avoid getting wet, antennas are designed and built for a specific purpose. I've talked at length about these variations, but in summary we can alter the dimensions to alter characteristics like frequency responsiveness, gain, weight, cost and a myriad of other parameters.

If we take a step back and look at two antennas, let's say a vertical and a horizontal dipole, we immediately see that the antennas are physically different, even if they're intended for exactly the same frequency range. Leaving cost and construction aside, how do you compare these two antennas in a meaningful way?

In the past I've suggested that you use a coax switch, a device that allows you to switch between two connectors and feed one or the other into your radio.

If you do this, you can select first one antenna, then the other and listen to their differences. If the difference is large enough, you'll be able to hear and some of the time it's absolutely obvious how they differ. You might find that a station on the other side of the planet is much stronger on one antenna than on the other, or that the noise level on one is much higher than the other. Based on the one measurement you might come to the conclusion that one antenna is "better" than the other.

If you did come to this conclusion, I can almost guarantee that you're wrong.

Why can I say this?

Because one of the aspects of the better antenna is dependent on something that you cannot control, the ionosphere, and it is changing all the time.

I have previously suggested that you listen to your antenna over the length of a day and notice how things change, but that is both time consuming and not very repeatable, nor does it give you anything but a fuzzy warm feeling, rather than an at least passing scientific comparison.

A much more effective way is to set up your station, configure it to monitor WSPR, or Weak Signal Propagation Reporter transmissions using one antenna, for say a week, then doing it again with the other antenna.

If you do this for long enough you can gather actual meaningful data to determine how your antenna performs during different conditions. You can use that knowledge to make more reliable choices when you're attempting to make contact with a rare station, or when it's 2 o'clock in the morning and you're trying to get another multiplier for the current contest.

You don't even have to do anything different and spend little or no money on the testing and data gathering.

You can do this with your normal radio and your computer running WSJT-X, or with a single board computer like a raspberry pi and an external DVB-T tuner, a so-called RTL-SDR dongle, or with an all-in-one ready-made piece of hardware that integrates all of this into a single circuit board.

If you want to get really fancy, you can even use automatic antenna switching to change antennas multiple times an hour and see in real-time what is going on.

You also don't have to wait until you have two antennas to compare. You can do this on a field day when you get together with friends who bring their own contraptions to the party.

If there's any doubt in your mind, you can start with a piece of wire sticking out the back of a dongle. I know, I'm looking at one right now. I've been receiving stations across the planet.

One thing I can guarantee is that the more you do this, the better you'll get a feel for how the bands change over time and how to go about selecting the right antenna for the job at the time.

I'm Onno VK6FLAB

The origins of names of things in Amateur Radio has a long and internet riddled history, with hear-say and false memories added.

The humble BNC connector was patented in 1951. BNC doesn't stand for Baby N-Connector, Bayonet N-connector, British Naval Connector, Berry Nice Connector, Berkeley Neucleonics Corporation or any such name. Apparently, it's named after it's inventors Paul Neill and Carl Concelman, the Bayonet Neill-Concelman connector. They went on to invent the Threaded Neill-Concelman connector, the TNC. A sub-miniature version of these connectors came in three types, A, B and C, called SMA, SMB and SMC.

Also, the N-type connector was invented by the very same Paul Neill at Bell Labs, and the C connector came from Carl.

The Yagi antenna, was invented in 1926 by Shintaro Uda in collaboration with Hidetsugu Yagi, both of Tohoku Imperial University in Japan. It's actually called an Yagi-Uda antenna. Yagi described the antenna in English in 1928 and his name became associated with the antenna.

The PL-259 and SO-239 connectors are not so clear-cut. The PL for plug and SO for socket seems to be agreed on. There are several explanations on the numbers, but the most persistent one seems to be that it was a US army part number. They're also referred to as UHF connectors and if you know that they were invented in the 1930s, you'll understand that UHF frequencies started at 30MHz and "above", which in practical terms meant 300MHz. An interesting thing to note is that a standard banana plug mates properly with an SO239, so you can just plug your long-wire straight into the socket.

Of course we have the Volt, the Ohm, the Ampere and the Farad, named after Italian physicist Alessandro Volta, German physicist Georg Simon Ohm, French physicist and mathematician André-Marie Ampère and English physicist Michael Faraday.

Everything is named after something. Sometimes we even remember what that was and where it came from.

What things have you learned about names in Amateur Radio?

I'm Onno VK6FLAB

Today I'm going to talk about SWR or Standing Wave Ratio. As amateurs we use this term all the time, we expect to see it on a meter or display near our transmitter, we buy specific gadgets to measure it and often we seek to find the lowest possible SWR.

As I've said in the past, the perfect antenna cannot exist, in the same way, a perfect connection, the feed-line, between an antenna and transmitter can also not exist. The perfect match is a 50 Ohm match, but a dummy load is a perfect match and its purpose is specifically not to radiate. So what's all this about then?

Lets start in a swimming pool for a moment. Imagine that this pool is really long and skinny. Say 100m long and 1cm wide.

Stand on one side and make a splash. The ripple of the water radiates from the source of the splash, you, to the other end of the pool. The end wall bounces the ripple back to you, and bounces back and forth until all the ripples have dissipated.

Now, if you kept splashing about, and waves were rippling back and forth while you were splashing, some of the ripples would happen at the same time as a splash and some of the ripples would happen at the time between two splashes. That means that at some times the splash and the reflections would sit on top of each other, making a higher wave and at some times splashes and reflections would be sitting below each other, making the troughs between splashes deeper.

If you replaced the water with electricity and the pool with a transmission line, the same is true. If you made an electronic splash, say a transmission from your radio, into the feed-line, the ripple would travel along the feed-line, bounce off the end, come back, bounce off the radio and so on. In the same way, reflections and transmissions can add to each other, and they can also subtract from each other.

This difference between the addition of signals and the subtraction of signals is what we call the SWR.

There are two ways to get to the SWR. If you connect a 50 Ohm feed-line to a 100 Ohm antenna, the SWR is 2:1. This is a theoretical SWR and it tells you is that there will be a ripple coming back from the antenna that is both adding and subtracting from the original transmission.

Alternatively we could use an SWR meter to measure the voltage differences between the high and the low part of a wave and indicate on a dial what the SWR is. This is an actual SWR. The two are indicating the same thing and we can use that to get from a measurement to an understanding of impedance matching between the feed-line and the antenna.

As a point of reference, if there are no ripples bouncing back, then there is no addition or subtraction, and the resulting SWR is 1:1. For completeness, I should point out that the rabbit hole is much deeper than this explanation and I'll revisit this topic in the future.

Now for the final piece of the puzzle.

A piece of coax in Amateur Radio is 50 Ohm. If you have an antenna that is 50 Ohm, that's perfectly fine as an antenna system.

Of course, antennas are not so accommodating. A dipole has a feed-point impedance of about 75 Ohm. A folded dipole has a feed-point impedance of about 300 Ohm. Each different antenna system has a different impedance and thus needs a different transmission line connected to it.

So, if you look at a 50 Ohm coax connected to a 300 Ohm folded dipole, you know that the SWR is going to be 6:1. However if you connected a 300 Ohm ladder-line to the same folded dipole, the SWR would be 1:1.

What this means is that the coax would have waves rippling back and forth and the ladder-line would not. The coax would have a particular loss and each ripple going back and forth would be subjected to that loss, where on the ladder-line, the loss would only apply once, on the outbound leg, since no energy would be bouncing back. As an aside, this loss is experienced as heat and if you're not careful it will melt your coax or worse.

That's not to say that SWR kills everything, but you need to be aware of what's actually going on.

Now I should point out one more thing.

These bouncing waves, the ripples coming back have information embedded on them. If you're transmitting voice, or some digital mode, the ripples that bounced back would be broadcast with a slight delay and the second bounce with another slight delay, and so-on. This phenomenon could actually make your signal into gibberish.

Coax has its place. It's a very flexible way of getting a signal from A to B, it's not affected by crazy nearby signals and it's robust, not to mention cheap. If you actually need to get your signal somewhere, then it will pay to look at how best to use it, when to use ladder-line and how to organise your shack in such a way that the best signal makes it outside to the working end of your radio.

I'm Onno VK6FLAB

The other day I was woken by the sound of a thunderclap. It was shockingly loud and came out of the blue. A few moments later, it happened again. I exploded out of bed, rushed to the shack, disconnected the beacon power and switched the antenna coax to "safe".

After breathing a sigh of relief, everything went dark and with it came the distinctive sound of the sudden death of the uninterrupted power supply taking with it my workstation.

With nothing else left to do, I reported the outage to the power company, went back to bed, pulled the covers over my head, snuggled in and surprisingly, slept pretty well despite the barrage of water hitting my QTH. The next morning the power was back on and I discovered that one of the residual current devices, the one that powered most, if not all, the wall sockets had tripped. I reset it and much to my surprise, most of my QTH came back to life.

I say most, because after breakfast I had a moment to switch on my radios and see what, if any, damage there was. I could hear and trigger the local repeater, but HF was strangely dead. I could hear the coax switches turning on and off, but the SWR on the antenna was high and it didn't appear that the antenna coupler was doing anything. It's powered remotely using a device called a Bias-T. You use two of them to transport a power supply voltage along your antenna coax. In my case, I inject 12 Volts in my shack, and extract the 12 Volts at the other end near the antenna where it powers the antenna coupler.

Occasionally the antenna coupler needs a reset, so I removed the power, waited a bit and reconnected. Still no response from the coupler, so I disconnected the power and left it for another time.

A few days later I had a moment to investigate further, so I went outside to check out the antenna and coupler. Both looked fine. I removed and reinserted the power, heard a click, but wasn't sure since a car came barrelling down the road at the same time, so tried again and heard nothing.

At this point I decided that this warranted a full investigation and started putting together a mental list of things I'd need. I wanted to test the coupler when it was isolated, I wanted to do a time-domain-reflectometry, or TDR test, to see if anything had changed. This test uses the RF reflection of a cable to determine its overall length and any faults like a cable break, high or low resistance and any joints. If you have a Nano VNA or an antenna analyser, you can do this test. It did occur to me that I didn't have a baseline to compare with, so that was disappointing, but I added it to the list.

First thing to test was to check if the radio had been affected. I turned it on, did the same tests and discovered that the Bias-T was still disconnected, which could explain why I didn't hear a click when I tested a second time. Armed with a level of confidence around power, I tried again to trigger the antenna coupler and got nothing, dread building over the potential loss of a radio in the storm, I set about swapping my HF antenna to another radio.

At this point I was reminded of an incident, 37 years ago, as a high school student during a class outing. My wonderful and inspirational physics teacher, Bart Vrijdaghs, took us to the local University where the head of the Physics Department of the University of Leiden gave us a tour of their facilities. He took us into a student lab full of oscilloscopes and tone generators and set-up a demonstration to show us how you could generate Lissajous figures. He was having some trouble making it work and with the impertinence reserved for teenagers I quoted a then popular IBM advertisement from 1985, "Of Je Stopt de Stekker Er In", which loosely translates to asking if he had plugged it in.

I can tell you, if looks could kill, I wouldn't be telling this story.

Suffice to say, it wasn't. Plugged in, that is.

Back to my HF antenna.

Yeah. It was already plugged into the other radio, so, unsurprisingly it was unable to send any RF to, or from, the first radio, much like some of the advanced telepathic printers I've had the pleasure of fixing during my help desk days a quarter of a century ago.

After all that, I can tell you that HF seems to work as expected. The beacon is back online and I have some work ahead of me to create some baseline TDR plots and perhaps a check-in, check-out board to keep track of what's plugged in where.

That and looking for another UPS, since keeping the computer it's connected to up and running, at least long enough to properly shut down, would be good.

What other lessons can you take away from lightning hitting nearby?

I'm Onno VK6FLAB

In our hobby we regularly talk about its purpose, its need, its usefulness and other potentially abstract notions. Often there's a nod towards science, learning, self-discovery, challenge, emergency service or some other higher order concept. I know I've discussed many of those over the years and encouraged you to find what the hobby means to you.

There is one aspect of our hobby that's pretty much left unsaid. It's left unsaid because it's obvious, since radio is about communication at its heart, the idea that we use our radios for communication is ingrained and unheralded. You might find a few new amateurs talking about how they made their first contact on the local repeater, or how they want to use the hobby to stay in touch when they're out and about.

It occurred to me the other day that much of the world is subject to travel restrictions and social or physical distancing requirements. There's places that are in total lock-down and whilst there are strong recommendations for people over 70 to stay completely isolated, that's not yet a requirement where I live. It might come to that, but at the moment the COVID-19 pandemic is changing habits and communities on an hourly basis.

Technology is often sought as a solution. There's plenty of video-conferences being held. Local amateur clubs are going online to stay in touch with members while face-to-face meetings are off the menu. Then there's the ongoing access to social media, blogs, discussion groups, mailing lists and the like.

There are a few brave radio clubs using something a little less technical. The radio. Shock, horror, imagine that, an amateur radio club using an actual, you know radio, to talk to each other. I must admit that communication via radio, as obvious as that sounds isn't always the first thing that comes to mind. I've lost count of the number of times when at the local club one member stood outside yelling back into the shack which way the rotator on the Yagi was pointing whilst adjustments were being made - turns out that the rotator was spinning on the mast in the wind. Took a concerted effort, seriously, to actually turn on a hand-held radio and talk to each other, like civilised people.

On the weekend during F-troop, a weekly net for new and returning amateurs, I also asked how people were doing given the social isolation that is pervasive.

I also started toying with the idea of running an F-troop every day, then I scaled it back to every Wednesday and Saturday and then it occurred to me that the power to host a net is in the thumb of any amateur clicking their push to talk button and I finally settled on continuing the normal activity of hosting F-troop on Saturday morning at 00:00 UTC for an hour.

I understand that in a technically connected world with cheap internet and fully functional gadgets like smart phones, the idea of going back to radio might seem like a step backwards, but I'd like to point out that we're radio amateurs. That's like being a chef and ordering take-out when you have a fully stocked kitchen.

If you're experienced in this hobby you'll know that nobody needs to grant you permission to host a net, but if you're new here you might not. So, to you I say: "You don't need permission to host a net, so get to it."

There are some things I've learnt since starting F-troop nearly a decade ago. Start small. Depending on the skill-level of the participants, choose an option for hosting it. F-troop is run with a single net-controller, often that's me, and the role of net-control directs who's next to talk. If you're just playing around, the tried and true version is a round-robin net. You'll need to pay attention a little better because you'll need to know who comes after you so you can hand the call to them. There are also variations on this, but again, start small.

I track contacts in a spreadsheet, but a piece of paper is just fine. Writing down all the stations you hear is a great idea, since it helps you keep track of who's said what. You can add information as it comes to hand. If the net is on HF you might record the signal strength you see when you're listening to each station, as well as the name and location or QTH.

Pro-Tip, use a new piece of paper for each net and put a date on it. Future you will love you for it.

My point is that there should be absolutely no impediment to getting on air, making noise and breaking isolation from the comfort of your own shack.

I'm Onno VK6FLAB

The hobby that we call Amateur Radio has been around for over a century. During that time we've seen it evolve from capacitors, inductors, through valves, then diodes and transistors, through to integrated circuits, chips and surface mount components. Along the way we collected a vast body of knowledge and experience which combine to make the hobby what it is today.

You might have noticed that the progression of our hobby didn't stop with surface mount components, it's still evolving through software and the next frontiers are already tentatively being explored and offered for sale to curious amateurs.

In my day job I'm a software engineer and I adopted Amateur Radio as my hobby of choice because it was technically diverse, had a rich history, a large community and had little to do with my day to day pursuits in computing and information technology. How wrong was I?

This morning I started writing code to visualise audio, specifically in my case to make a video version of this weekly segment, but also to experiment with how we as humans use our senses to decipher information. As I was buried inside the decoding of audio it occurred to me that what I was doing was the equivalent of soldering together a circuit for the purposes of learning more about some aspect of my hobby.

This in turn made me realise that as we dive deeper and deeper into the software defined radio universe, more and more of what we as individuals can do will be based on computers, algorithms and maths.

On the face of it, this is an enormous shift in perspective, but I'd hazard that it's no different from moving between a spark-gap transmitter and an AM transmitter, or moving from AM to SSB, or the introduction of transistors. Each of those changes now look pretty small with hind-sight, but at the time that they occurred their impact must have been immense.

I made contact with the software defined radio community a few weeks ago and in between my work I'm slowly beginning to explore this new universe that is beginning to unfold.

Of course, as this evolution happens, while we're in the middle of the transition, as-in right now, there'll be discussion about the difference between digital and analogue, between hardware and software, about the benefits and pitfalls, no-doubt mirroring prior discussions that have been had across the past generations of amateurs.

A new dawn has come and the future is here, come and join the fun.

I'm Onno VK6FLAB

What's in a word?

When you join a new community you learn very quickly that each community has its own language. A word in one community has a different or extra meaning in another. For example, the word "Snowflake" in one community might refer to a phenomenon related to water and freezing, in another community it refers to a person who is sensitive, easily hurt and offended. If you mix the two meanings all manner of misunderstanding ensues.

In amateur radio, one of those words is the word gain.

This word is used in many different aspects of our hobby, but today I'm going to focus on one specific use of it, in relation to antennas, antenna gain.

This mythical property of an antenna is often used as a way to distinguish two different antennas and in advertising terms, bigger is better, more gain, more better. I'll skip over the marketing shenanigans related to artificially making the number larger by comparing apples and pears, or dBi and dBd and move on to how gain comes about.

Let's look at something completely different. A light bulb. One of those tiny ones you find in a torch, or on the front of your bike or even one in your car. In essence we have a gadget that emits energy in the form of light and heat when electricity is applied. The specifics aren't important, but let's just say we're going to ignore more voltage and more amps for the moment.

If you have a bare light bulb, light and heat radiates in almost all directions. You can't see any light where the fitting is, but everywhere else is a pretty uniform pattern. For the moment, let's ignore the fitting.

If you were to get a piece of black cardboard and drill a hole and put the light through it, you've essentially removed half of the light. Below the cardboard there is no light. Above the cardboard is the same amount of light as before. Half the light is being stopped by the cardboard and it's essentially lost - technically it's getting absorbed and the cardboard is getting a little warmer, but let's not confuse the issue for the moment.

If you were to make the cardboard reflective, say some foil, white, a mirror, whatever, the light that was hitting the cardboard would be reflected away from the cardboard and you'd experience that as the light getting brighter. Notice though, it's still dark below the cardboard.

In essence you've just increased the gain of your light bulb and it didn't cost you any more electricity to make that happen.

Antennas work in much the same way. There are a few more wrinkles. A light bulb is working with light and heat frequencies, wavelengths are between 100 micrometers and 100 nanometres, where the antennas we use in amateur radio typically look at 100 meter to 23 centimetre, so the material aspects of our mirror equivalent are different, but have a similar idea.

One thing that's fundamentally different between a light bulb and an antenna in our hobby is that a light bulb is generally only transmitting, where we tend to both transmit and receive with an antenna.

Remember when I skipped over the bit of the light bulb below the cardboard being dark? That's the antenna equivalent to not hearing something, which means that you're better able to hear the signal in the direction you're pointing. The same is true for the bit about the light bulb fitting and no light below it.

In antenna terms, this phenomenon relates to the front-to-back ratio. Imagine turning your antenna 180 degrees. Pointing one way the signal is of this strength, pointing the other way it's that strength. Divide the two. If they're the same, the front-to-back ratio is 1, otherwise they express the directivity of the antenna. Another number you can use to market your antenna to an unsuspecting amateur.

So far we've only looked at using a single reflector for our light bulb, but if you were to use a torch, you'd get even more directivity and more gain. The same amount of energy, pointing at a smaller area. The ultimate expression of this is a laser beam, which is essentially a single focussed beam of light with no light anywhere other than where it's pointing.

Antennas do the same thing, using different methods, but the most common one is to add more bits of metal to focus the radio energy.

A light bulb emits energy in all directions and an antenna does too. Even if you were to make an antenna made of elements, all aligned in the same direction, the pattern is still mostly round, that is, it's like a cone of radio, regardless of the shape of the antenna.

Yes, there are ways of making antennas that don't make round cones, but that's a conversation for another day, but think about this, what would happen if you were to squash an antenna pattern and then focus it?

I'm Onno VK6FLAB

The other day I had an interesting exchange with a contest manager and it's not the first time I've had this dance. As you might know, pretty much every weekend marks at least one on-air amateur radio contest. Following rules set out by a contest the aim is to make contact or a QSO with stations, taking note of each, in a process called logging.

Using logging software is one way to keep track of who you talked to, a piece of paper is another. If your station is expecting to make less than a dozen contacts per hour, paper is a perfectly valid way of keeping track, but it's likely that most contests expect you to transcribe your scribbles into electronic form. Which electronic form is normally explicitly stated in the rules for that contest.

While I mention rules, you should check the rules for each contest you participate in. Rules change regularly, sometimes significantly, often subtly with little edge cases captured in updated requirements.

On the software side, using electronic logging, even transcribing your paper log, can get you to unexpected results. I participated in a local contest and logged with a tool I've used before, xlog.

Contests often specify that you must submit logs using something like Cabrillo or ADIF. There are contests that provide a web page where you're expected to paste or manually enter your contacts in some specific format.

Using xlog I exported into each of the available formats, Cabrillo, ADIF, Tab Separated Values or TSV and a format I've never heard of, EDI. The format, according to a VHF Handbook I read, Electronic Data Interchange, was recommended by the IARU Region 1 during a meeting of the VHF/UHF/Microwave committee in Vienna in 1998 and later endorsed by the Executive Committee.

The contest I participated in asked for logs in Excel, Word, ASCII text or the output of electronic logging programs. Based on that I opened up the Cabrillo file and noticed that the export was gibberish. It had entries that bore no relation to the actual contest log entries, so I set about fixing them, one line at a time, to ensure that what I was submitting was actually a true reflection of my log.

So, issue number one is that xlog does not appear to export Cabrillo or ADIF properly. The TSV and EDI files appear, at least at first glance, to have the correct information, and the xlog internal file also contains the correct information. Much food for head-scratching. I'm running the latest version, so I'll dig in further when I have a moment.

In any case, I received a lovely email from the contest manager who apologised for not being able to open up my submitted log because they didn't have access to anything that could open up a Cabrillo file. We exchanged a few emails and I eventually sent a Comma Separated Values, or CSV file, and my log was accepted.

What I discovered was that their computer was "helping" in typical unhelpful "Clippy" style, by refusing to open up a Cabrillo file, claiming that it didn't have software installed that could read it.

Which brings me to issue number two.

All these files, Cabrillo, ADIF, TSV, CSV, EDI, even xlog's internal file are all text files. You can open them up in any text editor, on any platform, even Windows, which for reasons only the developers at Microsoft understand, refuses to open a text file if it has the wrong file extension. This "helpful" aspect of the platform is extended into their email service, "Outlook.com" previously called "Hotmail", which refuses to download "unknown" files, like the Cabrillo file with a ".cbr" extension.

With the demise of Windows Notepad, another annoying aspect has been removed, that of line-endings. To signify the end of a line MacOS, Windows and Linux have different ideas on how to indicate that a line of text has come to an end. In Windows-land, and DOS before it, use Carriage Return followed by Linefeed. Unix, including Linux and FreeBSD use Linefeed only; OS X also uses Linefeed, but classic Macintosh used Carriage Return. In other words, if you open up a text file and it all runs into one big chunk of text, it's likely that line-endings are the cause.

It also means that you, and contest managers, can rename files with data in Cabrillo, ADIF, CSV, TSV, EDI and plenty of other formats like HTML, CSS, JS, JSON, XML and KML to something ending with "TXT" and open it in their nearest text editor. If this makes you giddy, a KMZ file is actually a ZIP file with a KML file inside, which is also true for several other file formats like DOCX to name one.

Of course, that doesn't fix the issues of broken exports like xlog appears to be doing, but at least it gets everyone on the same page.

Word of caution. In most of these files individual characters matter. Removing an innocuous space or quote might completely corrupt the file for software that is written for that file format. So, tread carefully when you're editing.

What other data wrangling issues have you come across?

I'm Onno VK6FLAB

One of the recurring topics in on-air discussion is that of antennas and if we were to graph the topics of conversations, antennas would be the clear winner in any line-up. As a beginning Amateur this phenomenon bamboozled me for a very long time.

Why are these people talking about antennas all the time and what's there to know that you can't say in 30 seconds?

From the mouths of babes...

I've mentioned in the past that Amateur Radio is to a very large degree magic. Another way of expressing that is to say that there is an Art to being an Amateur and antennas play a big part.

A friend of mine loaned me his antenna kit called a Buddipole. It's a portable set-up that is akin to Meccano or Lego in that you can build up an antenna from parts and make a large range of antennas from the same basic parts, two coils, a feed point, a balun, two telescopic whips and some extension pieces.

For me this particular antenna has been temperamental and I couldn't get my head around how to make it work. This all changed last weekend when I had a spare 15 minutes, literally, 15 minutes when I went into the shed to have another look. This was spurred on by a note that I'd read that pointed out that the Buddipole is asymmetric, that is, both legs and coils are not the same.

This important tid-bit of information made things click in my mind and all of a sudden I realised that I didn't need to make both sides the same length, or adjust both sides in the same way.

Until that moment I'd always thought of the Buddipole as a dipole on a stand and expected like any traditional dipole it would have both legs at the same length.

What if you could move the feed point along the length of your dipole, what would happen? What if you kept the overall length the same, but by making one end longer and the other end shorter, you in effect were moving the feed point along your dipole?

Wonderful things start to happen, that's what.

What I'm saying is that you don't have to make a dipole have equal length legs and that sometimes this is desirable.

Previously I've mentioned that the height of a dipole, the wire thickness, the ends, the angle and so on all affect the feed point impedance. Turns out, that where you place the feed point also affects this.

If you recall basic antenna theory, you might recall that the middle of a dipole is the lowest impedance and that the end of a dipole is the highest impedance.

Each of these values are on a continuum, that is, they vary as you change things. That means that between the two extremes of impedance there are other in-between values. If you have a balun, you can use this to get a great match for your antenna by tweaking these values.

Another example of this continuum is a loop antenna. If you make it twice as high as wide, the feed point impedance is 50 Ohm, but if you use the same loop and squash it flat, the impedance is 300 Ohm. Varying the shape changes the impedance.

In essence this means that there is an infinite number of antennas that can be made just as a dipole and another infinite number of antennas that can be made as a loop.

So, just two antenna types alone already gives you a lifetime supply of options and that's ignoring the height, soil or wire.

Now you understand why antennas are tricky and why we talk about them so much.

It also explains why the Internet is full of different explanations on antennas, since they are all based around the local conditions under which the author is describing their adventure.

Next time you hear an Amateur going on about their antenna, perhaps there's something to take away.

I know I won't be anywhere as impatient listening to others talking about their contraptions.

Final thought. A vertical is a dipole too. The radials are one half, the vertical the other. You can change the length of either, or both, but you can also feed the antenna in a different location.

I'm Onno VK6FLAB

Radio Waves travel in straight lines. They go from point to point and that's it. Except that Radio Waves also reflect off certain surfaces, like light does.

So, Radio Waves travel in straight lines and they also reflect and that's it. Except that Radio Waves also change direction when they pass through some change of medium.

So, then, Radio Waves travel in straight lines and they also reflect and refract and that's it. Except that Radio Waves also bend when they encounter an obstacle or a slit.

So, ok that's it. Radio Waves travel in straight lines and they also reflect and refract and diffract and that's the end of it. Except that they turn slightly due to gravity when they pass by a large mass.

So, this phenomenon that we use in our hobby every time we key up a transmitter or listen to an off-air signal is doing much that is invisible. It bends and wobbles, bounces and shifts, reflects and refracts and somehow we still manage to make our signal get from here to there.

The reason I'm raising this at all is that all new entrants to the hobby often scratch their head when they start transmitting. Antennas and propagation aside, the humble hand-held portable radio, the walkie talkie, or handitalky, or whatever you call it, does some weird stuff.

Some people use it like a mobile phone, other talk into it like they're summoning the oracle, others wave it about and hover around metal doorways or hold it close to their body and walk about while they're talking.

I host a weekly radio net, you should check it out some day, Saturday Morning, 0:00 to 1:00 UTC, it's called F-troop and we get lots of different skill levels and experiences sharing stories and answering questions.

Many times we have amateurs who are using a hand-held and getting unexpected results.

This variable, fluid nature of radio waves is why this happens. Each tiny variation causes some effect and some outcome. Resulting in a wildly fluctuating signal that varies between loud and clear and inaudible and all steps in between. And that's not even talking about flat batteries or trying to talk through a hill to a local repeater.

My point is that radio waves are unpredictable. If you are using your radio in an unpredictable way while using an unpredictable medium like radio, then all bets are off.

Next time you key up your hand-held, spare a thought for what's happening between your antenna and mine.

I'm Onno VK6FLAB.

In over a decade of writing a weekly article about all manner of different aspects of our hobby and community, I've never once talked about power connectors for your radio. It's so universal as to be invisible and rarely discussed. So much so, that something you do out of habit, makes another stop dead in their tracks and ask themselves why they never thought of it.

Despite how you might feel at the time, there's no such thing as a stupid question. The other day a fellow amateur Dave VK6KV asked about a power connector he'd seen at the local electronics store. That question started a group discussion about powering radios and how best to achieve that.

The very first thing to discuss is that the vast majority of amateur radio transceivers expect a nominal voltage of 13.8 Volt DC. That might sound like a strange requirement, but it's the voltage that comes from a fully charged 12 Volt lead acid battery, which is what many radios use as a power reference.

The next thing to consider is that a transceiver can draw quite a bit of power when it's transmitting. My Yaesu FT-857D user manual suggests 22 Ampere, but I've never seen that in the decade it's been in my possession.

When you purchase a radio, you'll likely discover that it either comes with bare wires, or some random connector that doesn't fit anything else. In many cases I've discovered that people cut off that connector and replace it with whatever standard they've come up with in their shack, but when they take their kit out on a field day, or acquire a new radio, the problem starts all over again.

Let me suggest a different approach.

The Anderson Power company, founded in 1877 by brothers Albert and Johan Anderson in Boston Massachusetts, make a range of connectors called the Anderson Powerpole and they come in a variety of ratings, sizes, shapes and colours.

First introduced as a standard by the ARRL Emergency Communications Course in December of 2000, after previously being adopted by amateur operators in California, the Anderson Powerpole PP15/45 series was selected. The Coordinator for Hawaii State Civil Defense RACES, or Radio Amateur Civil Emergency Service, Ron, then AH6RH, now KH6D has a detailed description on his QSL page on how this came about.

As a result, the stackable, asymmetric, genderless plugs are in wide use within the amateur community. The plugs are designed to be joined together using various orientations, creating a unique connector to suit your purpose. The Amateur Radio Emergency Service or ARES standard is one such orientation and before you adopt the Anderson Powerpole in your shack, make sure you use their orientation to avoid magic smoke from escaping your equipment.

Picking a connector is just step one.

When you acquire a new piece of 12 Volt equipment, you can cut off the connector and replace it with the ARES Anderson Powerpole connector orientation. Many amateurs I know then throw away the unusable connector, or shove it into a box for later.

Instead, what I do is, terminate the plug that you just cut off in exactly the same way. Essentially, from a visual perspective, you've kept the power cable intact, but inserted a Powerpole join into the lead. As a result you now have a standard Powerpole power lead and you have a new Powerpole adaptor to suit the new connector.

For that reason alone, I tend to bring a box of spare Red and Black Powerpole connectors to any field day and use the opportunity to spread the love around.

As I said, the individual plugs come in a variety of colours, I have a selection of eleven in my shack, where for me a different colour means a different voltage or purpose. For example, I've adopted green as the colour for antenna radials.

One challenge I'd not been able to resolve, until suggested by Ben VK6NCB, was how to avoid plugging a 12 Volt power supply into something that expects say 7.5 Volts. Colour alone isn't sufficiently idiot proof, especially in the dark. Ben suggested that I adjust the orientation of the plugs, preventing connectors of different colours to mate. Looking back, I can't understand why I didn't think of that in the decade I've been using them.

I will note that there are other Anderson connectors in use. A popular one is the grey double connector, used in portable solar installations and caravans. I'd recommend that you consider if you really want to plug your radio directly into a solar panel or not and choose your connectors accordingly.

Before you ask, to my knowledge the Anderson Power Company doesn't know I exist, nor did I get compensated in any way to say Anderson Powerpole. It's the ARRL Emergency Services standard and I'm happy to advocate for its use everywhere I go.

So, whether you're using bare wires, banana plugs, Molex connectors or some other random barrel connectors, consider cutting the lead and inserting Anderson Powerpole connectors.

When was the last time that you had to do the 12 Volt connector dance?

I'm Onno VK6FLAB

Identifying the problem is the first step in fixing it and with that I want to talk about emergencies. One of the very first things I was told about our amateur radio community was that we're here for when emergencies happen. Our purpose is to communicate, so in a crisis, we can assist by supplying communication to the situation.

I've talked about some of this before. Preparedness in the way of on-air training by contesting, in getting gear ready and even exercises for when this occurs. There are amateur clubs dedicated to putting up repeaters for just such an eventuality.

Recently there was a local news item about radio amateurs banding together, sending gear to fellow amateurs who were hit by severe flooding that wiped out their shack and with it their ability to communicate.

Another event was a friend who lost a big chunk of his shack when his basement flooded.

Across Australia and in other parts of the world in recent times we've been witness to the most devastating fires that destroyed entire towns and communities, taking with it infrastructure, communications, not to mention stock, local flora and fauna and entire wildlife ecosystems, bringing some to extinction levels.

The destruction doesn't end there. War and famine, drought, cyclones, hurricanes or typhoons, snow storms, heatwaves and the like.

All those situations can to greater or lesser degree benefit from amateur radio communications, either for amateurs affected, or for the community at large.

I started considering what would actually be required to be useful in such a situation. Could you be prepared for anything, or are you required to pick and choose? What does "being prepared" actually look like and what steps can you take once it's happening?

I asked myself if sending radio gear to amateurs who are affected by floods is the most effective way to actually help, or would it be better to pass the hat around and send the proceeds to their bank account?

Should you as an amateur drive into an emergency area and start communicating, or are there better ways to help?

There are local amateur radio emergency service groups under various names in different countries, some of which are highly effective, others much less so.

One attempt I made was to join the local volunteer state emergency services. For several reasons that didn't work out for me, but it remains a viable option for some.

Joining those types of groups gives you a framework, but does it actually answer the underlying question, that of effectiveness?

I have a drawer full of emergency service training manuals, each more dense than the next, but very little of it relates to the amateur radio. Many pages are dedicated to search and rescue, staying alert, first aid, keeping alive, hand signals, log books, mapping and the like.

I am left wondering why we as a community, with a proud century of activity, having one of the main principles as emergency communication appear to have such a poor track record of actually considering what dealing with an emergency looks like and what your own individual place could be in that situation.

We document our radios, antennas, power supplies, contacts, circuit board designs, contesting procedures and all the rest of it, but we don't seem to do the same for emergencies.

Why is that?

In my opinion, it's time to document emergency amateur radio and if you have already started, get in touch.

I'm Onno VK6FLAB

The first clause of the original Amateur's Code reads:

The Amateur is Gentlemanly. He never knowingly uses the air for his own amusement in such a way as to lessen the pleasure of others. He abides by the pledges given by the A.R.R.L. in his behalf to the public and the Government.

The 2022 ARRL handbook version states it like this:

The Radio Amateur is CONSIDERATE...never knowingly operates in such a way as to lessen the pleasure of others.

Today the ARRL website presents it as:

The Radio Amateur is CONSIDERATE...He/[She] never knowingly operates in such a way as to lessen the pleasure of others.

It's surprising to see the addition of the He/[She] pronoun when nothing is added by doing so, in fact for some amateurs this actually reduces its relevance, something which I've spoken about before.

We could just simply change the words to remove the pronoun entirely, but does that actually cover all of what we want it to mean? Should this consideration be limited to operating, or should we go beyond that? What about conduct in a club setting, or on social media, email or SMS?

Some of these activities are conducted as a radio amateur and some are not. If we're limiting ourselves to amateur radio, not an unreasonable place to start given that we're talking about a document called "The Amateur's Code", we should really discuss the nature of amateur radio today.

I find myself in a community of amateurs, not a radio in sight, exchanging thoughts, opinions and experience that go beyond the concept of operating. I will note that there are legal definitions in our hobby that describe the notion of operating that do not include QRZ.com, email or Reddit and there is an argument to be made that operating falls strictly within the bounds of a licensed amateur activity.

That said, since "no man is an island", first uttered in 1624 by John Donne, neatly illustrates that although we're licensed amateurs, we do more than key our radios alone and even when we do, there are activities that affect others who are not operating as such.

When we discuss things with each other, face to face, that's not a licensed activity, even if both of us are amateurs. Neither is sending an email to another amateur, or commenting on a social media post. Standing in a club and teaching is also not a licensed amateur activity and cannot be considered under the idea of "operating".

All of what this clause is attempting to say is to be considerate. Don't reduce the pleasure of others by doing things that are unacceptable. It goes to how you are expected to be, to conduct yourself, to behave.

To incorporate this idea that what you do with other amateurs goes beyond operating, I think the word "operate" needs to be changed to the word "behave".

I'd also like to explore the word "gentlemanly" from the original text. Synonyms for this include civilised, courteous, honourable and polite to name a few. It seems to me that words like that would benefit our interactions within our community, not to mention beyond it.

One word that comes to mind is "respectful", something that lies at the heart of how we conduct ourselves towards each other.

So, if we drop the pronouns, update the word operates and add in respect, a revised clause one could be:

The Radio Amateur is CONSIDERATE and RESPECTFUL...never knowingly behaving in such a way as to lessen the pleasure of others.

Let me hasten to point out that I'm proposing this as a starting point for discussion. This is an activity that should go beyond one individual, it should also go beyond a single organisation. Amateur Radio is a global activity and it would do well for us to consider all of humanity when drafting a code of conduct which is essentially what the Amateur's Code is attempting to achieve.

So, how would you approach the first clause, what do you like, what do you think is missing, what would it need for you to consider it words to live by?

I'm Onno VK6FLAB

The other week I participated in a contest. This particular contest was on the 80m band, around 3.5 MHz. The contest itself, while worthy of a mention, the Harry Angel Memorial Sprint, runs for 106 minutes and commemorates every year of Harry's life, at the time, the oldest radio amateur in Australia.

I made two contacts. Count 'm and weep. Two.

So, you could do the thing that I might have done in a previous contest, smiled, thought, "Wow, that's not very many contacts." and got on with life. You're free to do that, but I wouldn't be talking about this today if I shared your view. In fact I'm sure that in my activities as a radio amateur I've managed to learn, and in some ways unlearn some things along the way.

In a previous contest I might have operated a club station, made contacts a plenty, added to the overall club score, added new countries and multipliers, had some good natured ribbing to go along with it and walked away with nothing to show for it on my own log.

The truth is that for many of my on-air contest activities I made contacts for other callsigns, those of fellow amateurs, clubs, special events, you name it, I made contacts.

Don't get me wrong, there's absolutely nothing wrong with that, nor was it a waste of time. I learnt loads from those experiences, but my own callsign log rarely, if ever, got an outing in such activities.

So, this contest was for me. For my callsign, using my radio, my antenna, my location, my patience and my skills. I did the contest because I wanted to, for me.

As you know, I'm a fan of operating QRP, that is, low power, so this contest I used 5 Watts, a Yaesu FT857d, a multi-tap vertical antenna, screwed onto a mount on the back of my car, parked next to a river with water to the East of me, so I could benefit from any gain that water nearby might offer me.

As an aside, I'll talk more about water and gain at some other time, because it appears that not is all as my handed-down in hush-hush terms from mentor to me, would have me believe. I don't yet know enough to point at anything, but there's more than apparently meets the eye. Watch this space.

Anyway, two contacts. Not even that far from me, about 230km South and 20km North East. Both with SSB. I heard about 20 stations, some up to 3,500km away, but they were dealing with S7 noise where I had none. That's right, no noise, S0, in the middle of the city.

In addition to a heart stopping moment when the lights came on in the car park where I had set-up, my biggest fear being noisy lights, which turned out to be unfounded, my other take-aways were that I really should bring spare batteries for my LED lamp, and that I called it an LCD lamp last week. Not sure what I was thinking.

I logged using pen and paper, in doing so I was upholding a fine tradition of radio amateurs everywhere, pen and paper is by far the most popular method of logging and with two contacts made, that's not surprising.

I'm still on the lookout for sensible logging on a phone, but so-far that's eluded me. Perhaps I should write one and sell it, become rich and famous, retire, become loved in the community, kiss babies ... who am I kidding?

Seriously though. What would the ideal phone based logging app look like to you?

As for the baby-kissing famous one, let me know when you meet them, I'll stay away.

I'm Onno VK6FLAB

Mistakes are common in all aspects of life. Sometimes they are only known to you, other times they are public knowledge and open to ridicule and lambasting. Getting on air for the first time is an accomplishment and often the initial source of mistakes, mishaps and great frustration. Once you've made it on air, the reception to this feat is often underwhelming, people around you don't appear to appreciate the amount of effort you went to in order to key your microphone and for others to be able to hear that.

If you've been in this community for a while it's easy to forget what is involved to make that first contact and to dismiss those around you who've managed to obtain their license, acquire their equipment, install and configure it just so and to actually achieve the first visible milestone in their amateur radio journey, though technically it's audible.

If you've never done this, or if you have but have delegated it to the historical backwaters of your mind, here's an outline of some steps and mistakes along the path of making your first contact.

The first question you're likely to ask is, which radio followed quickly by, from where? Then, if you're like me and many other starting amateurs, you'll have set up your radio for operation on the local 2m or 70cm repeater, you're likely to have some kind of vertical antenna with the microphone gain and squelch set just so and have your radio set for FM. I'm skipping over power, the electrical type, but that in itself can be a feat of endurance.

After hunting around for a list of relevant frequencies, you might also have set up something like CTCSS to ensure that your signal actually gets acknowledged by the repeater.

If that's not enough, you'll also have made your radio use an offset which makes it receive using one frequency and transmit using another.

There's possibly more things you've had to do to make this work and not be subjected to the ire of the local repeater troll who appears to delight in telling you off when they feel you've done something wrong, like leave the roger beep activated or some other infraction.

If you did manage to achieve all these things and actually made your first contact on the repeater, congratulations and welcome to the hobby! Take a breath, you did well.

After a while you're likely to become more familiar with your radio and start exploring the local bands. You might program another repeater into your radio and even experiment with local simplex frequencies.

Each of these activities brings a new experience and new mistakes. For example, not all repeaters use the same offset, or even an offset in the same direction. Not all repeaters have the same CTCSS requirements.

If you're using a simplex frequency, remember to turn off the squelch - don't ask me how I know - so you have a chance to actually hear the other stations, even if you are using FM as the mode.

The process of getting on air as a first time user can be daunting, with many different points of failure along the way.

Ignore the trolls, try your best and ask for help if you get stuck and celebrate your accomplishment when you manage to make a contact.

My point is that achieving all this isn't trivial and it would be helpful if that's remembered from time to time. It's easy to dismiss an achievement made by another, but much more rewarding to celebrate it.

I'm Onno VK6FLAB

Recently I received a lovely email from Simon G0EIY, who reminded me that there is a voice-keyer that fits into a microphone. It was designed by Olli DH8BQA as a replacement for a standard Yaesu MH-31 microphone. I'd come across this a while ago and for several reasons put off actually ordering one, but Simon's encouragement tipped me over the fence and I've placed my order.

What I'm expecting to arrive at some point is a kit that has the minuscule surface mount components already soldered to a circuit board, leaving a couple of individual components ready for my soldering iron abuse. I'll let you know how it goes.

This little experience reminded me that I've been stumbling across solutions like this for years, an amateur with an itch to scratch and the drive to do something about it.

For example, Paul KE0PBR likes to operate satellites and in doing so amassed a collection of frequencies. Since the Doppler effect alters the actual frequency depending on the satellite coming towards you or moving away from you, there are corrections that need to be done. If you're in the field, this is something that you might struggle with, so Paul created a Frequency Cheat Sheet.

If you're looking into magnetic loop antennas, you'll quickly encounter a spreadsheet made by Steve AA5TB that will get you started with the parameters for designing and building your own magnetic loop.

The popular VK Contest Logger, known colloquially as VKCL was built by Mike VK3AVV. It's a simple to use logging tool that has a large collection of rules for different contests and Mike often brings out a new version to incorporate the latest rule changes just before a contest. It even incorporates a station log.

If you've come across apps like DroidPSK, DroidSSTV and DroidRTTY, they're the brain children of Wolfgang W8DA. The increasingly popular Repeaterbook maintained by a global community of volunteers is the work of Garrett KD6KPC.

I've lost count of the number of radio amateurs running an online shop where you can buy gear, or kits, or circuit boards, components, antennas, software and the like, not to mention an astonishing collection of professionally built tools like antenna analysers, filters, amplifiers and more.

It's said that amateurs are notorious for their short arms and deep pockets. I like to think of it as a discerning and informed customer. It's easy to sell snake-oil to the masses, it's been going on for centuries, it's much harder to do that when the person you're selling to knows how the thing you're selling works and knows how to read a data-sheet, let alone ask awkward questions when the need arises.

Before I go on I will mention that the people I've named here are unaware of me doing so. I've not been approached by any of them to mention their name and I have no relationship, other than being a happy customer. I'm saying this out loud because this podcast goes out on amateur radio repeaters all over the world and commercial use of amateur radio is strictly prohibited.

You might have gotten to this point wondering why I'm even taking the time to highlight some of the efforts I've come across and the reason is very simple. This activity is everywhere, you just have to look. It's not like Olli, Paul, Steve, Mike, Garrett or Wolfgang shouted their involvement from the rooftops, it's just that the information is available if you care to look. Remember, these people are radio amateurs just like you and I.

That's important because the difference between a tool that you're using that you built, sitting in your shack or on your computer and that of the people I've named is that they took an extra step and shared their efforts with the community. Some amateurs are making a living from this hobby and I applaud their efforts, for the rest of us, me included, that's often not the point.

Invention is happening all over the world, right now. You are doing it, despite your protestations to the contrary. You might have made a PDF that you carry around during a contest, or it might be a calculator you knocked up to figure out how to build something. It might be a circuit diagram, an app, a how to guide, a map or a video. All of these things are creations that can be shared to increase the amount of innovation that happens by people bouncing ideas off other ideas.

In 1675, Sir Isaac Newton said: "If I have seen further it is by standing on the shoulders of Giants."

You are one of those giants and the person who uses your contribution to make their own is standing on your shoulders.

What are you waiting for?

Publish, share, document, photograph and make available, it's how society makes progress and it's how amateur radio stays at the forefront of innovation.

Get on air and make noise is not purely restricted to the RF spectrum.

I'm Onno VK6FLAB

The other day I was getting ready to go out when rain started pelting down. Not unexpected in this part of the world at this time of year but inconvenient for my plans.

I didn't particularly want to carry an umbrella and the thought of wearing a rain hood brought back memories of water trickling down my back.

For reasons I'm not quite sure of, my eye fell on my hat on its hook at the door. The hat I wear in the heat of summer to keep my brain from frying, the hat I use whilst camping with my amateur radio friends, the hat I've worn whilst loading massive hay bales with a tractor and the hat I've worn swimming in the Ord River - well, a descendent, third generation if I remember correctly. I shook my head in disbelief, after donning my raincoat, put my trusty Akubra Territory on my head and stepped out into the rain. Perfect. Kept me dry, kept my glasses clear and no drips down my back.

You may well wonder what this has to do with radio and that's a fair question. I will preface this with a disclaimer that you might not have this set-up in your shack just now, but perhaps it will inspire you to get started.

I've been talking a lot about Software Defined Radio, and I do believe that it represents the future for our hobby, but that doesn't mean that my traditional radio, in my case a Yaesu FT-857d, is headed for the scrap heap just yet.

As you might know, with some preparation you can connect your radio to a computer and control it. You can also connect both the send and receive audio to a computer using a variety of techniques which I probably should get into at some point.

Assuming that you have, and I realise you might not yet have done this, but assuming for a moment that you have made this all work, you can use this to do things like JT65, FT8, PSK31, SSTV and hundreds of other modes.

One thing I did during the week was use this set-up to listen to noise. Seriously, that's what I did. I picked a spot on the band with nothing but noise. No discernible signal and fired up the application WSJT-X, it's the tool you use for many weak signal modes. As an aside, as a tool, it is also helpful in getting your digital mode levels set correctly.

One of the windows in WSJT-X is the waterfall and spectrum display. On it you can see the signal as it is right now and how it's been in the past.

If you turn on one of the filters on your radio, you can see the display change. You can literally see what gets filtered out. On my radio I've got the standard filter, as well as a 2 kHz and a 300 Hz Collins filter. Using this technique, you can specifically see what each filter does. If I turn on the built-in Digital Signal Processor, the DSP, I can see what the adjustments do, as well as the impact of the mode on the filter. And how the various settings interact.

For example, until I saw this display, I didn't know what the "DSP HPF CUTOFF" and "DSP LPF CUTOFF" specifically did and how they interacted with the other filters. Similarly what "DSP BPF WIDTH" did and how.

I also didn't know that even if you set both the high and low pass filter frequencies to the same value, you still have a usable filter, even if you might think that nothing could get through.

Now I do realise that your radio may not have those specific settings, but I am confident that if you pick a spot on the band, set up a frequency display and waterfall, you'll discover things about your radio that you hadn't before. I also realise that you can hear some of this by just playing with filters, but seeing it on the scope adds a whole other dimension to the experience. Just one example is to see how a narrow filter interacts with the in-built DSP, something that's difficult to hear, but easy to see.

If you have a Morse beacon to hand, you can also see how various frequency shifts work and the impact of selecting filters in relation to that signal. No need to just listen to the beacon with just CW mode either. Have a look at it using SSB.

Using something for an unexpected purpose can give you many great rewards. As for the hat, really, I hadn't used my hat to ward off the rain until then; you live and learn.

What have you discovered recently?

I'm Onno VK6FLAB

Today propagation is what it is, yesterday it was different and tomorrow it will be different again. It's one of the fundamental aspects of amateur radio.

We talk about propagation on air, like we do the weather. Rain, sun, snow or storm, there's always something. Of course most of those weather events have no impact on radio. A rain drop isn't going to make a great deal of difference to a HF signal, other than potentially making the operator wet, or creating a short-circuit in an unexpected way.

Propagation on the other hand has little or no effect in day-to-day life, other than your GPS, mobile phone or other electronic device. In radio however, propagation makes the difference between only hearing your neighbours and speaking to another station on the other side of the globe.

In the past I've mentioned that if you skip a stone across a lake, you get a good idea about how radio waves bounce off the ionosphere and in doing so, make it possible to hear and be heard beyond the line of sight of your antenna.

A stone is a fixed object and water has a pretty uniform density, so you get mostly predictable results. The ionosphere is not uniform and radio waves are not fixed, so the result is anything but predictable.

That said, a great number of people are working on providing propagation prediction tools in an attempt to provide us with somewhat more of a reliable outcome. Once you step into this area, you'll come across the A and K indices, the Solar Flux and Geomagnetic and Solar Flare numbers.

You'll find websites like solarham.com, bandconditions.com, spaceweather.tv and many others. Sometimes they'll even agree with each other - which is interesting in itself, since the source of actual data is pretty limited. We have the Ionospheric Prediction Service or IPS in Australia, in the US there's the National Oceanic and Atmospheric Administration, or NOAA.

All this is to attempt to quantify what the sun is doing and how this affects the ionosphere and in turn our experience as radio operators.

If you know anything about predicting the weather, that is, what is the temperature going to be today and is it going to rain, you'll understand that predicting solar activity and its impact on us is a less than perfect experience. In 1959 we managed to snap the first images of the far side of the Moon, it took until 2011 for us to do the same with the sun.

Many of our predictions are really observations and imperfect ones at that, coming from the two STEREO spacecraft, one orbiting the sun ahead of the earth, the other behind the earth, combined they manage to cover the back of the sun.

In the end, the predictions on carrying an umbrella or not are like predicting whether to operate or not. It's a prediction. Nothing beats turning on your radio and having a go.

I'm Onno VK6FLAB

Today I'm going to talk about dipoles. You know the tried and true antenna, the go-to design for getting on air, the simple first antenna you ever make, the one you learn from, you know the one. It's the mainstay of every amateur, of any field-day, of all things Amateur Radio.

It's a simple thing. Using metric, rather than imperial measurements, but the point stands, you use the speed of light in vacuum divided by the required operating frequency and you get the overall wave length for that frequency. In absolute terms, roughly 300 m/s divided by 50 MHz, gives you 6 meters. Surprise, that's the band name for 50 MHz.

Now the dipole is a half-wave contraption, so, 6 meters divided by 2 gives you 3 meters for your total half-wave dipole. Each leg is half that, a quarter wave length, so you have 3 meters divided by 2 again and you end up with two bits of wire, a meter and a half long each.

If you're following along, that's 300 divided by 50 divided by 2 divided by 2, or using the same numbers in a slightly different order, 300 divided by 2 divided by 2 divided by 50 MHz, or 75 divided by 50 MHz. Still one and a half meters per leg of your shiny new dipole.

So, the basic formula for a metric dipole can be stated as 75 divided by the frequency in MHz per leg. If you're playing with feet and inches, 300 m/s becomes 984 ft/s, half that is 492, half that is 246 feet, so the imperial version is 246 divided by the frequency in MHz, gives you length in feet for each leg.

So, you've cut your wires, tied them to some magical feed point contraption, plug it into your radio and you're good to go, right?

Now, anyone who's actually done this knows that this is not what will actually happen. It's never that simple, and frankly if it were, we wouldn't be Amateurs, we'd be, unlicensed or something.

So, what affects the actual length of this magical antenna? Lots and lots of things. Here are a few that come to mind:

- The thickness of the wire you're using. - The thickness of the insulation on the wire. - A thing called the end-effect. - The height of the contraption above the ground. - The kind of ground. - The price of the copper you're using.

Sorry that last one isn't right. I have been told, time and time again that there are only two kinds of wire, cheap wire and free wire. The preference is for the latter. So, price of the copper doesn't matter. Another thing that does matter is that some wire can stretch while in the air, making the antenna longer, so keep that in mind.

Fine and well I hear you say. But how does this really matter?

If you increase the thickness of the wire, the resonant frequency goes down, that is, the antenna is "too long". If you increase the thickness of the insulation, the resonant frequency goes down as well. The end-effect is like adding a capacitor to the end of the wire, making it "longer" as well. The height effect is different for each height. Generally the effect is that the antenna resonates at a lower frequency. Each type of ground has a different amount of effect. Water vs rock vs sand vs clay.

I can hear you groan at this point.

First comment to make is that all of these effects make the antenna resonate at a lower frequency. This means that the suggestion to cut your antenna longer than the calculated number doesn't make much sense. If you start with the basic calculation, 75 divided by the frequency in MHz, you'll end up with an antenna that's extremely likely to be too long.

I can hear you screaming at me right about now. Hold your tar and feathers. I gave you the First comment. Here's a Second one.

If you don't have space for a straight dipole, say, you need to go around a corner, or put a bend in the wire, all of what I just said goes out the window. If you put this above a metal roof, poof, also out the window. If you cannot terminate the wire to a rope without bending the end of the wire, poof.

A Third comment. You cannot cut wire longer. You can only cut it shorter. Cutting it longer is called soldering and that's a whole 'nother thing.

Let me finish with some tips for new players.

Don't ever cut your wire. It won't work like you expect and it will only give you more work. Always, always, always, fold your wire back over itself and wind it back over the end. If you leave it dangling you're adding capacitance and doing all manner of other weird stuff to your antenna.

Also, if you need extra length because the 80m dipole just won't fit into the back yard, you can use the end capacitance to good effect, hang it down towards the ground and you'll end up with an antenna more to your liking.

Final comment and then you can start sending me emails about how I'm wrong.

The humble dipole antenna is a magnificent contraption. It has more variables than you can poke a stick at and anyone who tells you that it's just a case of calculating this by doing a simple division hasn't got the faintest idea of what's actually going on. There are times when simplification is helpful. This is not one of those times.

So, have fun, play with your dipole, try different things and observe the differences when you try different things. I've spoken with Amateurs who've been doing this longer than I've been alive and they still can't calculate the actual length of a dipole, put it in the air and have it work first time.

Sometimes you get lucky. More practice, more luck.

I'm Onno VK6FLAB

In Volume 4 - Just get started - follow my journey through the amateur radio community, how to use QSL cards, mobile antennas on HF, licensing requirements, policing the airwaves, the super check partial list, packing up coax, lightning protection and more.

Search for my callsign - VK6FLAB - on your local Amazon store to have a Look inside.

Amateur radio is a thousand hobbies rolled into one. I hope you find your way.

I'm Onno VK6FLAB

Recently I made a comment about melting your coax and that this was a bad thing. Today I'm going to talk about some of how this comes about and what kinds of parameters we're dealing with.

Let's start with coax itself. The operating temperature of coax is somewhere around 80 to 90 Degrees Celsius, or 176 to 194 Fahrenheit. Soldering is at 230 Celsius, or 446 Fahrenheit, so for starters, soldering coax is a risky adventure.

For argument's sake, let's assume that you managed to solder your coax without damaging it. What else can go wrong?

Let's have a look at high voltage transmission lines. Why do we move power around the place using high voltage lines? The answer is that in a high voltage line, the current is low. Where the current is low, heating is low, so more of the energy gets from the power-station to your shack and less of it is used to heat up the power line between the power station and you.

So, that means that high voltage and low current is less heat loss. The opposite is also true. Low voltage and high current is more heat loss.

Now if you look at a dipole antenna, you'll know that this contraption is moving energy around at some or other frequency. As it's doing that, there are high and low voltage points and high and low current points.

In a half-wave dipole, the high voltage points are at the ends of the antenna, and the high current points are at the feed-point.

Guess where your coax is?

So, you've got your connection to your antenna located at a high current point, in the place where high current has the potential to create problems, things like heating up your coax and potentially melting it.

So, when does this heating happen?

Well, you need high resistance and high current. This typically happens when you've got a bad connector at the feed-point. In practical terms this means that if you're using QRP, 5 Watts, you're unlikely to come across a situation where this becomes an issue, since the currents aren't that high and a bad connection typically means no contacts.

If on the other hand you're using high power, then make sure that the connection to your antenna is strong, solid, and water proof so it doesn't deteriorate to the point of melting and then killing your radio.

It's best to keep an eye on the SWR meter when you're working, since a high SWR might be indicating that the resistance at your antenna changed for the worse.

Final comment. When you've set-up your station, create a note of the SWR at different frequencies and refer back to that regularly. Spotting a problem early might just prevent some expensive maintenance later on.

I'm Onno VK6FLAB

Today's Amateur Radio is less like the valve or transistor based radio and more like a computer. So much so that most radios today have a mechanism to connect the radio to a computer.

This mechanism is called a Computer Aided Tuning interface, or CAT interface. It's a mechanism that's used to allow two way control information to be shared between the radio and a computer.

This interaction is a serial connection, generally something called RS232. This is a standard that was developed in 1962 and it specifies things like timing, voltages and other attributes. The electronics from that era don't look much like the ones of today and most of the challenges with getting this stuff to work is related directly to these differences.

It should come as no surprise that each manufacturer has their own take on what this whole contraption looks like and most of this technology is not directly compatible across radios.

So, let's imagine that you've got a radio and a computer and they're physically connected to each other using a CAT interface of some description. We then need to make sure that things like the speed of both ends is the same, that is, the BAUD rate is the same. Also we need to check that the number of bits, stop bits and parity are also correct. If this sounds a little like 1980's modem talk, you'd be correct. The radio is presenting itself to the computer as a serial device, just like a dial-up modem does. If you've not seen this, just think of it as if the numbers at both ends need to match. Often the radio will have a standard setting, which you should use as a starting point.

Now, I'm going to skip over things like IRQs and port addresses, not because it's simple, but because it might work out of the box, or it might cause you to lose hair. If it's the latter, you're going to need to do some IT support and this is about radios and not about computers.

I'm also going to gloss over the problem that most modern computers don't have an actual serial port any more, most have something called USB which requires an adapter and software for the adapter, another potential minefield to traverse.

Now comes the bit where it all works, right? Nope. Not yet. Next you need to have software that knows how to talk to your radio. It may be programming software, specifically to configure your radio, or it may be generic logging software that reads what mode and frequency you're on and puts that in your log, or it may be something that knows how to correct the frequency of your radio to deal with the Doppler effect of an overflying satellite.

In each case, you'll need to tell your software several things. The most basic one of those is the port number. That is, of all of the serial ports on your computer, which one is connected to your radio?

Seeing that all Amateur Radio manufacturers agree on everything, all actual control codes and responses are the same across all radios. Oh wait, nope, that's not true. They're not even the same across the same brand, so you'll also need to tell your software which actual radio you're using, which is the perfect opportunity to learn that your shiny new radio doesn't yet exist within the software.

So, when you start looking at the CAT interface, you now know that this is a thing that's going to require some homework and planning.

To make digital modes work, you need an audio interface to go with the CAT interface, which a whole different set of fun and games, including ground loops, impedance matching, levels, feedback and distortion.

Now, if you thought that you and I took a lovely walk through the deep arcane world of serial computer interfaces, wrap your head around this.

When we use the current crop of software defined radios, we replicate all of this, both CAT and audio interfaces with virtual versions of cables, BAUD rates and port numbers. Suffice to say, I don't have words.

I should add that all of what I've said is just so you get an idea that there is a chain of stuff that needs to work and that any one of these being incorrect will cause none of it to work. So, when you're doing this in your own shack, start at the beginning, get the cable working, set the speed and bits, set the port, pick the radio and cross your fingers.

It's not trivial, but it's worth it.

I'm Onno VK6FLAB

In every new technology there is an ah-ha moment, the single one insight that defines for you personally what this technology is all about. No doubt this happened when Amateurs first used valves, when they started using transistors and so on. For me that moment happened during the week.

You've heard me talk about the absurd noise floor, that is, the incredible amount of local radio noise that I experience at my shack. I've been working my station portable to get away from the racket.

During the week I came across something that is likely to change that.

You've no doubt heard about diversity reception. You can use two different antennas, do some fancy phase switching and make the noise go away. Now I should clarify, at least briefly what that looks like. Imagine throwing a stone into a lake, it makes waves. If you throw two stones into the lake at the same time, the waves get bigger, but if you were to time it just right, you could throw in one stone, then the next. If you timed it just so the first stone would make a wave top whilst the other stone made a wave trough, the two would cancel each other out.

You can do the same with light, shine a torch onto a piece of cardboard with two slits cut into it. Behind the cardboard you'll see light and dark patches where the frequencies line up and cancel each other out.

Light and radio waves are part of the same spectrum, so you can do the same with radio waves. You could use this technique to cancel out, or rather filter, local noise.

So far I've not said anything particular worthy of ah-ha, but stick around.

There are devices made that you can use to create the equivalent of two slits, by changing inductance and capacitance within a specific circuit, you can align two signals from two antennas and make them cancel each other out. The way that works best is if one of the antennas is really good at hearing noise and the other is responsible for hearing the required station.

You can then mix the two signals, I don't have such a device, but I'm told there is an art to making this work, and out pops the station you care about.

In software defined radio or SDR, you can do this exact same thing. Only you don't need a circuit to do it, you can show the results in real-time and you can create a user interface that makes it really easy to try different things. The example I saw is PowerSDR, an open source project that allows you to control many different radios.

Picture a circle with a line that is attached to the centre of the circle and the end is attached to your mouse pointer. You can move the mouse anywhere in the circle and as you do this, you're controlling two parameters, the phasing angle and the gain. The gain is the length of the line, the angle is the direction in which the line is pointed.

While you're moving your mouse about, the signals from both antennas are mixed together according to the position of the mouse at the time.

The end result is a completely interactive direct feedback loop where you can see and hear the effect of the mouse location. You can move it around very simply, and immediately, continuously see the result.

The outcome of all this is that you can bring your noise floor down by 30dB or more, and hear stations that were completely inaudible within the racket.

I'd heard it being described, but seeing it in action was a show stopping moment for me and right there and then I knew that the landscape in radio has changed forever.

I'm Onno VK6FLAB

This and other episodes of Foundations of Amateur Radio can be heard via podcast or download at podcasts.itmaze.com.au.

There's nothing quite as satisfying as the click of a well designed piece of equipment. It's something that tickles the brain and done well it makes the hairs stand up on the back of your neck.

If time was on my side and I wasn't going somewhere else with this, I'd now regale you with research on the phenomenon, I'd explore the community of people building mechanical keyboards and those who restore equipment to their former glory, instead I'm encouraging you to dig whilst I talk about the second and third harmonics. This is about amateur radio after all.

Over the years there has been a steady stream of commentary around the quality of handheld radios. Some suggest that the cheaper the radio, the worse it is. Given that these kinds of radios are often the very first purchase for an aspiring amateur it would be useful to have a go at exploring this.

When a radio is designed the aim is for it to transmit exactly where it's intended to and only there. Any transmission that's not where you plan is considered a spurious emission. By carefully designing a circuit, by adding shielding, by filtering and other techniques these spurious emissions can be reduced or eliminated, but this costs money, either in the design stage, or in the cost of materials and manufacturing. It's logical to think that the cheaper the radio, the worse it is, but is it really true that a cheap radio has more spurious emissions than an expensive one?

To give you an example of a spurious emission, consider an FM transmitter tuned to the 2m amateur band, let's say 146.5 MHz. If you key the radio and all is well, the radio will only transmit at that frequency, but that's not always the case. It turns out that if you were to listen on 293 MHz, you might discover that your radio is also transmitting there. If you're familiar with the amateur radio band plan, you'll know that 293 MHz is not allocated as an amateur frequency, so we're not allowed to transmit there, in fact, in Australia that frequency is reserved for the Australian Department of Defence, and there's an additional exclusion for the Murchison Radio-astronomy Observatory.

293 MHz isn't a random frequency. It's twice 146.5 MHz and it's called the second harmonic.

There's more. If you multiply the base frequency by three, you end up at 439.5 MHz, the third harmonic. In Australia, that frequency falls into the amateur allocation as a second use, its primary use is again the Department of Defence.

These two transmissions are examples of spurious emissions. To be clear, the transmitter is tuned to 146.5 MHz and these unintended extra signals come out of the radio at the same time.

This is bad for several reasons, legal and otherwise. The first, obvious one, is that you're transmitting out of band, which as an amateur you already have no excuse for, since getting your license requires you to understand that this is strictly not allowed.

The International Telecommunications Union, or ITU, has specific requirements for what's permitted in the way of spurious emissions from an amateur station.

Spurious emissions also mean that there is energy being wasted. Instead of the signal only coming out at the intended frequency, some of it is appearing elsewhere, making the 5 Watts you paid for less effective than you hoped for.

So, what's this got to do with the click I started with?

Well, thanks to Randall, VK6WR, I have on loan a heavy box with a Cathode Ray Tube or Green CRT screen, lots of buttons and knobs and the ability to measure such spurious emissions. It's marked "HP 8920A RF Communications Test Set". Using this equipment is very satisfying. You switch it on and a fan starts whirring. After a moment you hear a beep, then the screen announces itself, almost as-if there's a PC in there somewhere - turns out that there is and the beep is the Power On Self Test, or POST beep. Originally released in 1992, this magic box can replace 22 instruments for transceiver testing. I started downloading user manuals, oh boy, there's lots to learn. Bringing back lots of memories, it even has a programming language, Instrument BASIC, to control it. Where have you been all my life? Turns out that in 1992 this piece of kit cost as much as my car. Anything for the hobby right?

At the next HAMfest I'll be using it to measure as many handhelds as I can get my hands on and taking notes. I have no idea how many I'll be able to test, but I'm looking forward to putting some numbers against the repeated claims of quality and price. I can tell you that a couple of weeks ago I got together with Randall and Glynn VK6PAW and spent an enjoyable afternoon testing several radios and there are some surprising results already.

Perhaps this is something you might attempt at your next community event, gather data, rather than opinions...

I'm Onno VK6FLAB

The origin of our amateur bands

It's hard to imagine today, but there was a time when there was no such thing as either the 80m or the 20m amateur band, let alone 2m or 70cm.

Picture this. It's the roaring 20's, the 1920's that is. Among a Jazz Age burst of economic prosperity, modern technology, such as automobiles, moving pictures, social and cultural dynamism, the peak of Art Deco, we're also in the middle of a radio boom where the world is going crazy buying radios as fast as they can be constructed, there are hundreds of licensed broadcasters, the bands are getting crowded, radio amateurs have been banned from the lucrative radio spectrum above 200 meters, and can only play in the "useless short waves" using frequencies greater than 1,500 kHz. And play they did.

On the 2nd May 1925 amateurs proved they could communicate with any part of the world at any time of the day or night when Ernest J. Simmonds G2OD and Charles Maclurcan A2CM made a daylight contact between Meadowlea, Gerrards Cross, Buckinghamshire, England, and Strathfield, Sydney, New South Wales, Australia on what we now call the 20m band. This contact occurred not once, but regularly, for several days, using 100 Watts.

To give you a sense of just how big news of this feat was, on the second scheduled contact the Prime Minister of Australia, Stanley Bruce, sent a message to England's Prime Minister, Stanley Baldwin: "On occasion of this achievement Australia sends greetings."

If you recall, the IARU, the International Amateur Radio Union, was a fortnight old at this point. Less than a year later contact was made using voice.

Between the banning of radio amateurs from frequencies below 1,500 kHz at the London International Radiotelegraph Conference in 1912 and the Washington International Radiotelegraph Conference in 1927 the world had irrevocably changed. In 1912 the discussion was almost all about ship to shore communication. By 1927, the world had tube transmitters, amplitude voice modulation, higher frequencies and what the 1993 IARU President, Richard Baldwin, W1RU calls, "literally an explosion in the use of the radio-frequency spectrum".

In 1927 individual countries were beginning to control the use of spectrum, but there was no universal coordination, no international radio regulation and as we all know, radio waves don't stop at the border.

Richard W1RU, writing in 1993 says: "In retrospect, the Washington conference of 1927 was a remarkable effort. It created the framework of international radio regulation that exists even today. It had to recognize and provide for a multitude of radio services, including the Amateur Service. It was at this conference that amateur radio was for the first time internationally recognized and defined. Bands of harmonically related frequencies were allocated to the various radio services, including the Amateur Service."

While the IARU was two years old, it really hadn't represented amateur radio on the international stage, until now.

The 1927 conference defined an "amateur" as a "duly authorised person interested in radio electric practice with a purely personal aim and without pecuniary interest."

The harmonically related frequencies that were allocated to the Amateur Service are recognisable today. I'll use current band names to give you some context.

1,715 kHz to 2 MHz, or 160m, 3.5 to 4 MHz, or 80m, 7 to 7.3 MHz or 40m, 14 to 14.4 MHz or 20m, 28 to 30 MHz or 10m, and 56 to 60 MHz or 6m.

Of those, the 20m and 80m bands were exclusive to amateurs. The 10m and 6m bands were shared with experimenters and the 160m and 80m bands were shared with fixed and mobile services. You'll notice the absence of bands we use today, the 2m and 70cm bands, 15m and the so-called WARC bands to name a few.

The final ratified document goes into great detail about the requirements, the restrictions, how to deal with interference, how to allocate frequencies and numerous other provisions, many of which will look familiar, almost a hundred years later, if you've ever looked at the rules and regulations under which you operate as a licensed amateur today.

There were various radio amateurs at the 1927 conference, but as Richard W1RU puts it: "much of the credit for the success of amateur radio at that conference has to go to two representatives of ARRL -- Hiram Percy Maxim, president of ARRL; and Kenneth B. Warner, Secretary and General Manager of ARRL."

While Richard points to their roles in the ARRL, you might recall that Hiram was elected international president of the IARU and Kenneth its international secretary-treasurer.

Whichever way you look at it, whichever organisation you credit, today we have amateur bands thanks to those efforts made nearly a century ago.

I'm Onno VK6FLAB

What would you do if you found that at random times your garage door opener didn't work, or the Wi-Fi network dropped out, or you couldn't switch off a light with an RF controller?

That's the position I found myself in and the times at which this was happening were madly unpredictable. One moment everything would work fine and the next all things radio would just stop.

As a radio amateur you're likely nodding your head and thinking, radio interference, there's some direction finding in your future. Sure enough, that's the case, but before that, I needed to know if the interference was random, if it had a particular pattern and how widespread it was, since it seemed to impact multiple different devices using different parts of the radio spectrum.

Initially I focussed on getting a recording of it. I turned on my radio, tuned it to a 2m frequency and recorded the noise. Only one problem. There was no noise. All I could see was an extreme signal strength, but it wasn't showing up as noise.

I enrolled the help of my RTL dongle and recorded some raw data, essentially capturing a 3 MHz slice of noise centred around 147 MHz. All that revealed was that there was noise. I already knew that.

At that point I decided that a bigger hammer was needed. Something you can do if you have a $5 RTL-SDR dongle and some free software, in my case I used a tool called rtl_power and a visualisation tool called gnuplot.

rtl_power is a nifty piece of software. It takes measurements and averages out the power level across the measurement range. To make it work, you specify a starting frequency, a stopping frequency, how big a step to use to average, how often you want to measure and for how long.

For my little investigation I started with measuring between 0 and 1.7 GHz, at 1 MHz intervals, every 2 minutes for 10 days. That creates a big CSV file that you can process with gnuplot into a picture that tells a thousand lies.

Seriously, it showed me that the interference was very wide, 0 to 300 MHz, it occurred every 20 or so hours, lasted up to six hour at a time. There were other things happening as well, similar patterns, but across an even larger frequency range, from 0 to 600 MHz, but in shorter duration and of lesser strength.

Based on the times alone, I can immediately, almost certainly, eliminate any source under my control.

Based on the timings I can also determine that the noise is likely not created by an automatic process, given that they vary in duration and the way they're clustered around specific times.

The variation of the interference allows me to determine that there are at least three separate types of noise, each with specific characteristics and times, sometimes overlapping.

It's too early to tell if this pattern will continue. One possible next step is to set up the same measurement tool and powering it from a battery. Once I've got that working, I expect to turn off the house power during an interference session and determine if the noise is coming from my house, or if it's an external source, which seems likely.

Once I've determined if it's in house or not, I can start either eliminating gadgets by switching off specific power circuits, or I can start direction finding and locating a nearby source of pain.

At that point I can decide what to do next. That said, at the moment it looks like several televisions around me are creating an RF noise storm of epic proportions.

I've documented all of how I did this and you can find it and the scripts I created on the web at vk6flab.com.

One thing that has happened since I started documenting my efforts is the idea that we could collectively as a community make measurements like this and document the state of our RF space and how it changes over time. I plan to update my code to incorporate this idea, perhaps log in 24 hour blocks and generate a chart over that time, perhaps make it into a video.

One challenge ahead of us would be to come up with a universal way to calibrate our various dongles, so we all report the same signal level in the same way. One thought is to use the sun as a global calibration, but I'm not yet sure how that might be implemented.

One thing's for sure. If you've ever wondered what use can a $5 RTL dongle possibly be, this is one thing that you just cannot do with a traditional radio. That's not to say there's a place for both in the world, just different tools for different problems.

I'm Onno VK6FLAB

Last weekend was memorable for all the right reasons. Filled with 24 hours of amateur radio, spent with friends, in a park, making noise and having fun, marking the first time I recall setting up in a park for that length of time with so few extra resources. Normally we'd be decked out with tents, or in my case a swag, we'd have camping stoves, perhaps even a caravan or two, tables, cutlery, the whole shebang.

This time we brought none of that. Just radios, antennas, batteries, water with a few snacks and folding chairs.

This was like nothing I've experienced before and it has me asking myself: Why did I wait so long to operate like this?

It was wonderful.

We spent it being on-air and making noise during a 24 hour contest which is specifically intended to celebrate and reward portable operation. In case you're wondering, the John Moyle Memorial Field Day is to encourage portable field day operation and provide training for emergency situations. It was created in memory of John Moyle, the long term editor of Wireless Weekly, who served in the RAAF with distinction. He's said to be responsible for a number of innovative solutions to keeping radio and radar equipment working under difficult wartime conditions.

I've participated in this contest plenty of times before. This was the first time I did it in a park, in the city, and as experiences went it was fabulous and recommended.

As you might know, I like operating portable. I've been operating from my car for years, from camp-sites in remote locations for just as long and I've activated several parks and peaks in Summits On The Air, or SOTA, and World Wide Flora and Fauna, or WWFF activities. I've also set-up during field days in local parks and I regularly drive to a local park to get on-air and make noise. With that as background, you might ask yourself, what is different?

Let's start with setting the scene.

The park that we used is located in a suburb about 10 km out from the city centre. It has a river running through it and on the banks there are plenty of trees with lawn. Dotted throughout are picnic tables with wooden gazebos. All very civilised.

From a radio perspective, it was RF quiet, that is, no local electrical noise, away from cars, from a footpath, close enough to parking where we could get our gear out of the car and walk it to the site.

All that alone would have made for a great experience, but this went beyond that.

For example, dinner consisted of ordering from the local fish and chips shop five minutes away and picking up some amazing seafood. While there collecting some extra water and most importantly dessert from the supermarket next door.

During our activities we had visits from local amateurs. Over the 24 hours we had a steady stream of interested hams coming out and having a chat. Some took the opportunity to bring food, dips and crackers, thermos flasks of tea, even ice cold beer. One amateur came along at the end of our activation and helped pack-up. All this made for a very enjoyable social experience.

Another thing that was different was that the operator could wear headphones without stopping anyone else from hearing what was going on. We achieved that by connecting a headphone splitter to the radio, piping the audio to some external speakers for local monitoring whilst the operator wearing headphones would not be affected by conversations taking place around them.

We did have some challenges.

Our logging tool of choice was, for reasons we don't yet understand, switching bands which meant that sometimes the numbers we were giving out were not sequential. Generally in a contest situation you exchange a piece of information in addition to a signal report. In this case it's supposed to be a sequential number and because there were multiple operators, the sequence is supposed to be per band.

The trees provided shade, but were not quite up to the task of being sky-hooks able to hold up wire antennas, fortunately we brought squid poles for that purpose.

It was hot. 38 degrees Celsius. It turns out that even though wearing a black long-sleeve T-shirt is not a suitable fashion choice from a temperature perspective, it was perfect in preventing sunburn and for that I was immensely grateful.

As you might know, we track what we bring in a spreadsheet, one row per item. A column for each time we go out. Over time we learn what's used and what's not. Our list is getting better and better.

I'll admit that I felt some trepidation in relation to this location, but I'm so glad that I took a leap of faith and went with the experience.

What a blast!

What kind of activities have you been up to that gave you a blast?

I'm Onno VK6FLAB

About ten minutes ago I was blissfully unaware of the existence of James K2MIJ. It's unclear if this bliss will ever be returned because it's obvious to me that James and I share several things, a sense of humour among them. Mind you, I've not yet actually spoken to James, other than me saying "Hello" right now, but his QRZ page is a thing of wonder.

Last week I was talking about weird and wonderful antennas. As you know, Amateur Radios don't particularly care what you plug into the back, as long as it looks like a 50 Ohm load, the vast majority of transceivers will happily transmit into them. I've heard of people making contacts with dummy loads, bits of wet string, chairs and as I said last week, bridges and rail-road tracks.

James has made it his mission to tune up strange things. He's made a lawn chair dipole and is using it to contact all states across the US, with only 5 Watts. He's added more countries to his DXCC than I have - 53 - and while he's at it, he also made some other contraptions, a fork dipole, from two actual kitchen forks, his in-the-shack dipole and his latest contraptions, a collection of five and a half inch and nine inch antennas. You heard that right, a five and a half inch antenna for 40 meters.

If you go to James' QRZ page, you'll find a kitchen table, holding an antenna farm that rivals those of many stations. Antennas for 40, 30, 20 and 17 meters.

One thing that piqued my curiosity is a photo of his 20m antenna sitting on the ground. Picture something like a peanut butter jar lid with a piece of copper stuck in the middle, standing up. It's wound around in a spiral with two windings, sort of like a big loading coil you'd find on a 2m vertical antenna.

The base of the contraption has about 30 or so windings on it which you connect between the copper and the feed-line.

The thing that got my interest was what was on the other side of the feed-line, a tape measure. More precisely, a steel tape measure.

As I said, I've not yet spoken to James, but it might be that his mini-antenna is mostly made of tape measure. Don't get me wrong, I think experimentation is wonderful and he's clearly made more contacts that I have, but I'd love to learn what effect the tape measure has on his contraptions.

I noticed a few other things that people have tuned up, beer cans, especially helpful with Fox Hunting, when one of your friends, or should I say Fiends, sets up a secret transmitter that you and several teams have to track down. The more devious the antenna installation, the better.

There's the quintessential flag-pole antenna for those times that your neighbours need to see that you're patriotic and not a nasty radio amateur with unsightly antennas that reduce the value of their home and remove the enjoyment of their life because your hobby affects their ability to sleep at night.

I've seen people tune up their gutters, even tried it myself - the noise floor in my shack prevents anything sensible, but I'm working on it - and of course there's the proverbial boat on a trailer antenna. No interest in sailing as such, just a nice tall aluminium construction that could perhaps be connected via some feed-line to a nearby radio transmitter. It's not even a permanent structure, so it'll add value to the neighbourhood.

Making a weird and wonderful antenna as an experiment is great for learning, it's great for experimentation and dealing with emergencies and it might keep your neighbourhood happy too - mind you, why anyone would think that an antenna is ugly is beyond me.

I'm Onno VK6FLAB

We think of radio as operating on a specific frequency. We select an antenna resonant on a single band. We configure the radio for that same band and then turn the dial or the VFO, or Variable Frequency Oscillator to a particular frequency within that band.

All of our language is geared towards this concept of tuning, of picking out, selecting one special tuned, resonant frequency and listening to it.

I've said this before, but that's not actually what's happening.

Your radio is receiving all RF frequencies, all of them, all at the same time, all the time. Your antenna is better at hearing some frequencies than others, but that doesn't stop it from hearing everything at once. Your radio is getting all that RF information at the antenna connector. After that, every step along the way is removing unwanted information, first it removes all the bands you're not listening to, then the VFO selects which part of what remains to let through to the decoder and the result finally arrives at the loudspeaker.

Ultimately, all your radio lets you play with is what's left over. Say about 3 kHz bandwidth. Using traditional radio, if you want to listen to two repeaters, you either need to switch back and forth quickly, or you need two receivers.

Now without going into how precisely, imagine an SDR with a bandwidth of 3 MHz, one thousand times larger than your traditional radio. Before you think I'm being fanciful, a $25 gadget can do this. This means that you could process most if not all of the 2m amateur band and then pick out which bits you'd like to decode. You could decode all the local FM repeaters, an overflying satellite, the International Space Station SSTV, a beacon, Morse, Packet, RTTY and simplex contacts, WSPR, APRS, EME, whatever is happening on 2m, all at the same time.

Let me say that again. All of the 2m band, all at the same time.

The point is that all this information is there, all the time. We can opt to decode or ignore the information. In a traditional radio, you can only decode one signal at a time, but on an SDR, you can extract as much or as little as your computer can handle. Some SDR language talks about using multiple receivers, but a better description is multiple decoders.

This means that software defined radio is fundamentally a different way of looking at radio spectrum. Instead of filtering out everything we don't want to decode, we select which decoder to apply to which part of the spectrum.

With an SDR you could represent the 2m band as a 3 MHz slice of spectrum as a series of measurements. There is no loss if you reuse the numbers, so if you process the same data multiple times, you have no loss of signal, no deterioration, no extra noise.

All we do is feed the same data into each decoder, pick out the bit we want to decode and have at it.

There is a misconception that you need serious computing power to do this. That's not strictly accurate. A $5 Raspberry Pi single board computer is more than powerful enough to do this. You can argue that this is serious computing power, compared to what we used to land on the moon it is, compared to your mobile phone, it isn't.

I fully intend to go into the maths behind this, but it's not scary, despite what you might think or have been taught. My week has been about the maths and it's become clear to me that there are lots of explanations around, each trying harder than the next to scare you away.

If you feel the need to run screaming for the hills when you hear the words Nyquist, Shannon and Fourier, then get it out of your system and come back when you're ready.

I'd like to mention that I've been working on how to explain this over much of the week, I've lost count of the number of drafts I've written, but it keeps coming back to the words that are almost as old as I am: My god, it's full of stars.

No doubt you might be convinced that I've lost my marbles and that I'm going well outside the Foundations of Amateur Radio, but I have to confess, this is what radio is today, and I'm thrilled to be here learning more about how this all works. Hopefully you are just as thrilled.

I'm Onno VK6FLAB

Where are all the Amateurs is a question that I am asked regularly by new entrants into our community. The journey most new amateurs go through and the one I followed starts with becoming interested, getting a license, buying a radio, setting it up and then turning on your radio. If you're lucky you are at this point surrounded by other amateurs, hopefully in a club setting, or you have a friend nearby and you're off and running.

The reality is likely that even after a successful first on-air adventure, you'll be on your own in your shack asking yourself where everyone went.

I've talked in the past about picking the right day, for example, a Wednesday is likely to have less people on air than a Saturday, but that's only part of the story.

One of the things that had never occurred to me until a while after I became an amateur is that listening is a really important way to find other amateurs.

Let's start with some things that might not have occurred to you.

Most amateurs are not in your time-zone.

There is amateur radio activity almost all the time, 24/7 on whatever the appropriate band is.

Not all bands sound the same.

What worked yesterday might not work today.

This hobby isn't exact or precise, that is, there are an infinite number of variables which each affect the experience either positively or negatively and even if you used your radio in exactly the same way with the same settings on the same band in the same location at the same time with the same antenna, the landscape around you has changed, the ionosphere is a lot like the ocean, flat and calm one day, storms and waves the next.

Those things aside, each of which could be a whole story is still only part of the story of finding other amateurs.

There is a tendency for new amateurs to think of frequencies as numbers, as parameters to add to your radio, pick 7.093 MHz, pick 21.250 MHz, or 28.500 MHz, they're just numbers, things that you pick with your radio, set-up your antenna to and listen.

That's part of the story, but there is another part.

If you think of light and you go from Infra-red through visible light through to Ultraviolet light and beyond, all you're doing is changing a number, from somewhere around 300 GHz through to 3 PHz. It's a long dial in amateur radio terms, but the difference is just a number, right?

It should be obvious that the human day-to-day experience of Infra-red and Ultraviolet are completely different. The 28.5 MHz 10m band frequency is on the same spectrum as both Infra-red and Ultraviolet but you don't expect to see these frequencies or use them in the same way.

The same is true for amateur radio bands. The 80m band, the 40m band, 15m and 10m are all different. They're in use by radio amateurs, but their experience is also completely different. Some are good for day-time communications, others for night-time, some work regardless of the solar-cycle, others need solar flux. Magnetic activity affects some bands more than others and that's just the tip of the iceberg.

If you have a hand-held radio and you're used to listening to a local 2m repeater it's likely that you've set up the squelch on your radio to hide noise and your day-to-day experience is one where there is silence when nobody is talking. You might tune to 15m and look for the same silence, only to learn later on that noise is what you're actually looking for.

The sounds that the 10m band makes is different than the 80m band, the 20m band responds differently to changing conditions to the 40m band and every different radio you use has a different feel, so what you're used to with one radio will be different on another.

All this to say that the way you find other amateurs is to listen. You'll need to get a feel for this thing, a sense of opportunity.

I've compared amateur radio to fly fishing on more than one occasion. Standing up to your arm-pits in a river tossing out a line, finding a bite will be different depending on the day, the temperature, how much you moved around and the appetite of the fish around you at the time. The more you do this, the more you get a sense of opportunity and the better your results.

Instantaneous gratification is going to be elusive, get used to it, be patient, be curious and experiment.

I'll leave you with this image.

I'm currently standing in my wardrobe, surrounded by clothes, shoes, boxes and jumpers in the middle of my home with the door closed, crammed in with my microphone stand, a laptop and a tablet in an attempt to ward off the background noise that comes from a winter storm that is currently overhead unleashing the first rain of the season in spectacular style.

Some days I fantasise that my budget could manage a recording studio or even a sound-proof booth.

I'm Onno VK6FLAB

The history of the evolution of amateur licensing is a nebulous affair, told and re-told, moulded, changed and interpreted by the story tellers along the way. There is an on-going debate about how the restructure of the licensing regime in Australia, in 2005, has affected our hobby.

In 2005, after a 10 month review period, three classes of license were established, a new Foundation class, an a re-imagined Standard and Advanced class, using existing novice and novice limited licenses to create the Standard class and combining limited, intermediate and unrestricted licenses into the Advanced class.

I've touched on this subject before, back in 2011, when I noted that those who forget history are doomed to repeat it.

The ACMA published the review in May of 2004. It summarises the responses about the introduction of the Foundation licensing option.

It opens with, "Over two-thirds of submissions were in favour of the introduction".

It goes on to say that the most common reason for support was the need to make the amateur service more accessible and cited that the Foundation class then introduced in the UK was the appropriate standard.

The majority of respondents suggested that the maximum transmitter output should be 100 Watts PEP and suggested 80m, 40m, 15m, 10m, 6m, 2m and 70cm as the appropriate bands.

Also of interest is that 39% of respondents were in favour of a two-tier licensing structure, where 24% were in favour of a three-tier structure.

The ACMA report also mentions that many respondents suggested that the foundation license should not be renewed without the licensee being re-examined.

If you're familiar with the restrictions and obligations of the Foundation License then you'll recognise that some of these responses were agreed to and some rejected. I've not included the full report, it goes to 15 pages, but there are some other interesting things in the ACMA report.

The ACMA notes that the main reason cited for requiring a Foundation licensee to be re-examined was to promote the license as a "stepping stone" to amateur radio operation. It notes that while there are provisions in the Act for such a re-examination, where there are reasonable grounds to believe that a qualified operator would be unable to achieve satisfactory results. The ACMA notes that none of the current amateur licensing options requires an amateur operator to be re-examined regularly.

I wonder if we actually forced all amateurs to re-do their license, how many would actually pass? I know I would.

There are other interesting things afoot. There is discussion today about allowing Foundation Licensees to use digital modes, but there is a move to require that it be added to the syllabus before that is permitted. Of course there is a parallel to make, none of the current licensees have any such formal training, why should a Foundation Licensee be "special" and require extra training.

I've been asked what I think about privileges and the Foundation License. To be clear, I'm perfectly happy with my privileges. I have yet to experience all that Amateur Radio offers, and by turning my operating power to half the permitted level, 5 Watts, I'm learning specifically what works and what doesn't. I'm learning about propagation, about antennas, about operating techniques and about patience. I'm sure that this stands me in good stead wherever I go.

One final comment, the ACMA report references a submission by a group called CQVK. I managed to track down the 112 page submission and have uploaded it to the F-troop website, the home of the weekly net in which New and Returning Hams can get together every week. Have a look at the ACMA report and the CQVK report at http://ftroop.vk6.net.

As I've said before, those who forget history are doomed to repeat it. Let's not.

I'm Onno VK6FLAB

When I started learning about antennas I was told height is might. The higher the better. For many years I've followed that advice and like a good little parrot I've dispensed that advice. Turns out that as is usual in our hobby, that's not the whole story.

I first came across a ground based antenna with a BOG, that's a Beverage On Ground antenna. It's essentially a long length of coax that's pointed at what you want to hear. You can either terminate the end, or not, different effects result with plenty of discussion about directivity, angles, lobes and the like.

One of the things you'll notice with you use a Beverage antenna is that it's quiet. All signals are reduced in strength, but that also means that noise is reduced. Turns out that this pays off and you hear stuff that you've not heard before. Excellent for a field day or if you want to hear some serious DX stations.

There's plenty of stuff that's not nice about a Beverage antenna. For one, it's highly directional, it takes up lots of space and if you want to listen in another direction, you'll either build a second or third and switch between them. That, or you'll be rolling up and laying out the coax to point at a new DX entity.

You also cannot transmit with a Beverage antenna. While we're on the subject, often a beverage can be combined with a vertical, one for receive, the other for transmit. It's one of the projects that lying in my to-do pile. I've even got a remote controlled coax switch, but I'm still figuring out how to make my FT-857d do the switching.

I could stop there, but I came across another idea a couple of weeks ago. At the time I was being introduced to the local emergency communications team. They showed me their HF stand-by gear. Long piece of wire that you could chuck out on the ground and make contact. As a good little amateur I remember thinking to myself, these poor people they have a lot to learn. I'm glad I'm an eager apprentice in learning the art of keeping my big mouth shut.

During F-troop, a weekly net for new and returning amateurs, you'll find details on vk6flab.com, another amateur was talking about putting a wire near the ground, like about a foot off the turf with great results.

I tried it on the weekend with a friend. We were out camping for a local amateur contest, miles from anywhere and anyone and I recalled the emergency communications people and the story during F-troop. We had some time to play, so we started with a long-wire, actually, pretty-much a wire dipole on the ground. Plugged it in, turned on the radio, magic. Same kind of sound effect as a Beverage antenna. Nice and quiet, good signals to be heard. We turned the whole contraption 90 degrees, no difference. Since then I've learned that it's pretty much omni directional and unlike a Beverage antenna, you can use it to transmit.

Of course it's not going to act in quite the same way as a dipole high in the air, and that's pretty obvious, since it's not in the air. It'll give you communications that are called NVIS, or Near Vertical Incident Skywave, essentially stuff that goes straight up and comes down, stations up to about 400 km or so away. For scale, that's enough to cover all of Holland. In Australia it's enough to cover the state of Victoria, or the width of the UK, and most of the width of the State of New York.

Before you get all huffy and point out that this is not a great DX antenna I'll beat you to it and tell you that this is not a great DX antenna. It's not meant to be. Nor is it intended to be an instruction on what antenna to build next. This is purely intended to illustrate that antennas come in all manner of shapes and sizes and there is lots to be learnt from trial and error.

I know that this is a "compromise" antenna. Guess what, so is every other antenna. Today the compromise is that we don't need any poles, trees or unsuspecting human support structures to keep an antenna in the air. You can essentially try this one for free at any time, on your own, on the beach, in a park or on the side of a mountain.

Another great use is to talk to your friends who live in the same city on HF. I have no doubt you could even manage some FT8 contacts using this antenna.

Next time someone tells you to put your antenna in the air, ask them who they want to talk to. If it's locals, then there is absolutely no need at all. As for mastering the art of keeping my big mouth shut, we'll see.

I'll leave you with this. It's not the answer that's important, it's the question, for everything else there's experimentation.

I'm Onno VK6FLAB