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Starting in the wonderful hobby of Amateur or HAM Radio can be daunting and challenging but can be very rewarding. Every week I look at a different aspect of the hobby, how you might fit in and get the very best from the 1000 hobbies that Amateur Radio represents. Note that this podcast started in 2011 as "What use is an F-call?".
Updated: 4 hours 22 min ago

Getting started on WSPR with a PlutoSDR

Sat, 05/08/2021 - 12:00
Foundations of Amateur Radio

As you might recall, I took delivery of a device called a PlutoSDR some time ago. If you're not familiar, it's a single-board computer that has the ability to transmit and receive between 70 MHz and 6 GHz. The system is intended as a learning platform, it's open source, you get access to the firmware, compilers and a whole load of other interesting tools. I used it to play with aviation receive using a tool called dump1090 which I updated to use Open Street Map. If you're interested, it's on my VK6FLAB github page.

Over the past few months I've been steadily acquiring little bits and pieces which today added up to a new project.

Can I use my PlutoSDR to transmit WSPR?

This all started because of an experiment and a conversation.

The experiment was: "Using my FT-857d on 70cm can I transmit a weak signal mode like WSPR and have my friend on the other side of the city decode the transmission?" The answer to that was a qualified "Yes". I say qualified, since we weren't able to transmit a WSPR message, but using FT8 we were happily getting decodes across the city. We're not yet sure what the cause of this difference is, other than the possibility that the combined frequency instability at both ends was large enough to cause an issue for a WSPR message, which lasts about two minutes. On the other hand, I learned that my radio can in fact go down to 2 Watts on 70cm. I've owned that radio for over a decade, never knew.

Now that I have a band pass filter, some SMA leads and the ability to talk to my Pluto across the Wi-Fi network, I can resurrect my Pluto adventures and start experimenting.

I mentioned that this was the result of an experiment and a conversation.

The conversation was about how to create a WSPR signal in the first place. At the moment if you run WSJT-X the software will generate audio that gets transmitted via a radio. All fine, except if you don't have a screen or a mouse. Interestingly a WSPR transmission doesn't contain any time information. It is an encoded signal, containing your callsign, a maidenhead locator - that's a four or six character code representing a grid square on Earth, and a power level. That message doesn't change every time your transmitter starts the cycle, so if you were to create say an audio file with that information in it, you could just play the audio to the nearest transmitter, like a handheld radio, or in my case a Pluto, and as long as you started it at the right time, the decoding station wouldn't know the difference.

As an aside, if you're playing along with your own Pluto, and far be it for me to tell you to go and get one, you can set the Pluto up using either USB, in which case it's tethered to your computer, or you can get yourself a USB to Ethernet adaptor and connect to it via your network. If you have a spare Wi-Fi client lying around, you can get that to connect to your Wi-Fi network, connect the Pluto via Ethernet to the Wi-Fi client and your gadget is connected wirelessly to your network. I can tell you that this works, I'm typing commands on the Pluto as we speak.

As is the case in any experiment in amateur radio, you start with one thing and work your way through. At the moment I want to make this as simple as possible. By that I mean, as few moving parts as I can get away with. I could right now fire up some or other SDR tool like say GNU Radio and get it to do the work and make the transmission, but what I'd really like to do is actually have the Pluto do all the work, so I'm starting small.

Step One is to create an audio file that I can transmit using the Pluto.

It turns out that Step One isn't quite as simple as I'd hoped. I located a tool that actually purports to generate an audio file, but the file that it builds cannot be decoded, so there's still some work to be done.

On the face of it the level of progress is low, but then this whole thing has been going for months. The experiment on 70cm lasted half an hour, the discussion took all of a cup of coffee. So far, I've spent more time on this project making the Wi-Fi client talk to my network than all the rest put together and that includes finding and ordering the Pluto in the first place.

You might well wonder why I'm even bothering to talk about this as yet unfinished project. The reason is simple. Every day is a new one. Experiments are what make this hobby what it is and every little thing you learn adds to the next thing you do. Some days you make lots of progress, other days you learn another way to not make a light bulb.

I'm Onno VK6FLAB

Ergonomics in your shack

Sat, 05/01/2021 - 12:00
Foundations of Amateur Radio

In my day job I work in computing. For many years that consisted of going on-site and fixing stuff. Invariably this involved me fixing servers that were installed into a room the size of a broom closet with an optional air conditioner screaming in my ear. The experience often included sitting on a crate, or the floor, holding a keyboard and if it was a Windows Server, rolling a mouse on my knee in order to click on stuff barely discernible on a tiny screen that likely sat a meter too high above my eye line with Ethernet wires going diagonally from one end of the room to the other.

These days with ubiquitous internet connectivity that kind of experience is mostly a thing of the past.

That said, operating a radio during a contest in many stations I've used over the years is not far from that kind of layout.

Often a traditional shack starts off with a radio on a table with a notepad to record contacts. Over time that gets expanded with technology like a computer. It's common to have to juggle the radio display and keyboard, to find a spot for the mouse that doesn't interfere with the desk microphone, or to have to reach over to change band and to activate a different filter, select another antenna, use the rotator or some other essential tool that's required for making that elusive contact.

Some stations have multiple monitors, sometimes they're even together, but more often than not they're a different size, sitting too high and the radio sits as a road-block between your eye line between the screen and the keyboard.

I'm raising this because over the years I've not actually seen anyone spend any energy on discussing how you might improve this experience.

If this was your workplace, the occupational health and safety police would be all over you and for good reason. You could argue that amateur radio is a hobby and that OH&S is of lesser concern, but to that I'd like to point out that you have the same risk of self injury at work as you do in your shack, especially if you're doing a contest for 24 or 48 hours.

Not only is there a risk of injury, why make the experience harder than it needs to be? Ergonomics is the process of designing or arranging a workplace to fit the user. It's a deliberate process. You have to actually stop to consider how you are using a space, in this case your shack.

At the moment I'm experimenting with different aspects of the layout of my shack. For example, I started with a layout of the computer, counter intuitive perhaps, since we're talking about a radio shack, but given that I'm spending much of my time doing contests and digital modes, the computer is used much more than the radio is, even if the radio is what's making all the on-air noise.

After making sure that my keyboard, mouse and screen were in locations that actually helped me, I started trying to figure out where to put the radio and what role it actually plays in making the contact. If during a contest you're using search and pounce, which is when you hunt up and down the bands looking for a contact, you might argue that you'll need access to the radio to change frequency, but if you already have your computer connected to the radio, you can change frequency from the keyboard or by control with your mouse.

Another way I'm looking on reducing the amount of stress to my body whilst operating my station is by sorting out audio. Almost every radio has a speaker on it, but if you've got more than one going at the same time it becomes really difficult to determine which one is actually making noise and even harder if multiple stations are on different frequencies on different radios at the same time.

You could wear headphones and select a radio, one at a time, either by plugging in a particular radio, or by using a selector. If you're using digital modes, the audio might already be going into the computer, which offers you the ability to select from different sound cards, but there are other options. I'm working on plugging the audio from each radio into an audio mixer that will allow me to set the level for each radio independently, mute at will, set the tone, the balance between left and right ear and a few other things.

For a microphone I plan on using the same mixer and I'm working on how to have my digital audio coming from the computer incorporated into the same audio environment, because the digital audio could just as easily be a voice caller using the same system.

For push to talk I settled on a foot switch a couple of years ago. That said, if I'm on my own, I tend to use VOX, or voice operated switching, which turns on the transmitter when microphone audio is detected by the radio. This will need some careful planning if I'm going to connect multiple radios, since I don't want to transmit the same message across each radio at the same time, but with computer control, that too can be addressed.

My point is that we have lots of technology available to us as radio amateurs to achieve what ever we need to. It takes extra effort to decide how you might go about making your environment a place where you can safely sit and operate without making life harder than it needs to be.

What kinds of different techniques and technologies have you used to make your shack a more comfortable environment? Do you spend your days hunting DX, doing contests or making digital contacts, or something else? Have you considered how you might improve the layout of your shack to suit your particular use-case and when was the last time you checked to see if the decisions you originally made are still valid today?

I'm Onno VK6FLAB

How much bandwidth is there?

Sat, 04/24/2021 - 12:00
Foundations of Amateur Radio

Have you ever taken a moment to consider the available bandwidth on the various amateur bands?

As an entrant into amateur radio in Australia as a Foundation licence holder you have access to six different amateur bands, the 80m band, 40m, 15m, 10m, 2m and 70cm. If you add the bandwidth from each of those bands together, you end up with 26.65 MHz worth of bandwidth to play with in Australia.

I can tell you that's a big chunk of bandwidth, but until I give you some context, 26.65 MHz isn't likely something that you can picture.

You might think of things as being pretty crowded. For example, on the 40m band during a contest it's common to hear wall to wall signals. There's barely enough room to call CQ and not interfere with anyone else. But how crowded is it really?

Let's start with an SSB signal, typically it's 2.4 kHz wide. On the 40m band, with 300 kHz of bandwidth, there's room for about 125 SSB signals side-by-side. On the 10m band, there's space for over 700 SSB signals side-by-side. Across all the available bandwidth for a Foundation license holder in Australia, there's room for over 11-thousand different SSB signals side-by-side.

While we're on the subject of crowding, there's talk about the massive influx of FT8, some call it a scourge. FT8 channels are transmitted within a single SSB channel and each takes up 50 Hz. That means that within an SSB channel of 2.4 kHz, there's room for 48 different FT8 channels, and if you take into account the odd and even time-slots, that doubles to 96 different signals, all within the same single SSB channel. So while FT8 is popular and growing, let's not get too excited about how much space it's taking up. From the perspective of an Australian Foundation license holder, it's taking up exactly six separate SSB slots of those 11-thousand across the six available bands, room for 576 separate FT8 signals, taking up a total of 14.4 kHz, or 0.05% of the available bandwidth.

Let's look at this another way, of the 26.65 MHz available bandwidth, 20 MHz is from the 70cm band alone, that means that all the other bands put together, fit inside the 70cm band three times over.

Let that sink in for a moment, adding the 80m, 40m, 15m, 10m and 2m band together fit inside the 70cm band three times.

You can use the 70cm band alone for 800-thousand FT8 signals, remember that there's two time slots, so you get two for one.

If this makes your mind explode, then consider that a carrier wave signal is considered to be about 25 Hz wide, so on the 70cm band you could have 800-thousand individual CW signals. You could allocate a personal CW frequency to every one of the amateurs in the United States in the 70cm band and still have room for expansion, not that I'm advocating that, just to give you a sense of scale. I should note that the 70cm band in the United States is even larger than it is in Australia, but I don't want to get bogged down into the various band plans across the world at the moment.

You might ask yourself why am I getting so excited about this?

Amateur radio is about experimentation. I've been telling you about HF propagation and using techniques like FT8 to determine just how far your signal goes, but you could use the same techniques to build a 70cm communication network with the amateurs within your city and share information across the city, perhaps even build a mesh network using your 70cm hand-held and an FT8-call network. It could be used to distribute propagation information, or messages in case of an emergency, or form the basis of something completely different.

If that doesn't whet your appetite, consider that the 1mm amateur band, which runs from 241 to 250 GHz is ready for you to experiment when your license permits. The current world distance record is 114 km, set in 2008 by Brian WA1ZMS and Peter W4WWQ, it has 9 GHz bandwidth and has room for 360-million FT8 signals, or 60 exclusive FT8 channels for every amateur on the planet.

My point is that as radio amateurs we have access to a massive chunk of radio bandwidth and it's just sitting there waiting for you to experiment with.

I'm Onno VK6FLAB

The massive physics phenomenon just over eight minutes away ...

Sat, 04/17/2021 - 12:00
Foundations of Amateur Radio

If you've been around radio amateurs for a little while you're likely to have heard about the Solar Cycle and that it affects radio propagation for HF or High Frequency, also known as shortwave communications. The frequencies in the range of around 3 to 30 MHz, or 100m to 10m wavelength. One of the main ways it's used is for is for long distance or global communication and one of the most common ways that's done is using the ionosphere around the globe to refract a radio signal.

In September 2020, the Solar Cycle 25 Prediction Panel, announced that Solar Cycle 25 had commenced in December 2019 and radio amateurs around the globe rejoiced.

The first question for me was, why Solar Cycle 25?

You might think of the Sun as a stable light in the sky. As it happens, the bright light hides all manner of ferocious activity. One of the measures of this activity is the number of dots observed on the surface of our Star. These dots are called sunspots. As Solar activity increases, the number of sunspots increases. The activity is cyclical, it increases and decreases over time. Each increase and decrease combined is known as a Solar Cycle.

On average a cycle lasts about 10.7 years. Simple maths gives you that Solar Cycles started somewhere around 1750. That seems a little strange. Our Sun is 4.6 billion years old. There are paintings on the rocks at Ubirr in the Northern Territory of Australia that are 40 thousand years old. The pyramids in Egypt are 45 hundred years old. The Solar Cycle has been going for a lot longer than the 7 million years there have been humans on the planet, let alone dinosaurs who experienced the Solar Cycle 66 million years ago. Using fossil records we've determined that the Solar Cycle has been stable for at least the last 700 million years.

Chinese astronomers recorded Solar activity around 800 BC and Chinese and Korean astronomers frequently observed sunspots but no known drawings exist of these observations. The first person to draw sunspots was John of Worcester on the 8th of December 1128. Five days later, half a world away in Korea on the 13th of December 1128, the astronomers in Songdo reported a red vapour that "soared and filled the sky", describing the aurora borealis in the night sky that resulted from those very same sunspots.

In the early 1600's there was plenty of activity around the recording of sunspots. Thomas Harriot appears to have predated Galileo Galilei by more than a year with notes and drawings dated the 8th of December 1610. There's plenty of other names during this period, Father and son David and Johannes Fabricius and Christoph Scheiner to name three, but I'm moving on.

The Solar Cycle, was first described by Christian Horrebow who more than a century later in 1775 wrote: "it appears that after the course of a certain number of years, the appearance of the Sun repeats itself with respect to the number and size of the spots". Recognition of the Solar Cycle was awarded to Samuel Heinrich Schwabe who noticed the regular variation in the number of sunspots and published his findings in a short article entitled "Solar Observations during 1843" in which he suggested that the cycle was 10 years.

Stay with me, we're getting close to Solar Cycle number One.

In 1848 Rudolf Wolf devised a way to quantify sunspot activity. His method, named the Wolf number, is still in use today, though we call it the relative or international sunspot number. In 1852 he published his findings on all the available data on sunspot activity going back to 1610 and calculated the average Solar Cycle duration as 11.11 years. He didn't have enough observations to reliably identify Solar Cycles before 1755, so the 1755-1766 Solar Cycle is what we now consider Solar Cycle number One lasting 11.3 years with a maximum of 144.1 sunspots in June of 1761.

Until 2009 it was thought that there had been 28 Solar Cycles between 1699 and 2008 with an average duration of 11.04 years, but it appears that the 15 year Solar Cycle between 1784 and 1799 was actually two cycles, making the average length only 10.7 years. I should also point out that there have been Solar Cycles as short as 8 years and as long as 14 years.

With the announcement of Solar Cycle 25 comes improved propagation for anyone who cares to get on air and make noise. The current predictions vary depending on the method used, ranging from a very weak to a moderate Solar Cycle 25. There are predictions for the Solar maximum, the time with the most sunspot activity, to occur between 2023 and 2026 with a sunspot range between 95 and 130. By comparison during the previous Solar Cycle, in 2011 the first peak hit 99 and the second peak in 2014 hit 101.

I have purposely stayed away from electromagnetic fields, geomagnetic impacts and the actual methods for HF propagation, I'll look at those another time.

I can tell you that we've gone a little beyond counting dots on the Sun to determine activity and we have a whole slew of satellites orbiting our Star doing all manner of scientific discovery, all of which helps our understanding of what's going on in the massive physics phenomenon 8 minutes and 20 seconds away by radio.

That said, Solar eruptions are still pretty unpredictable, much like the weather around us. Not because we don't want to know, but because this is a very complex one to solve, much like ionospheric propagation is hard to forecast, much easier to measure actual performance and much more accurate.

So, if you want to know how well propagation is going to be today, turn on your radio and have a listen. If you want to know how great it's going to be tomorrow, look at the forecast, but bring an umbrella, or an FT8 transmitter.

I'm Onno VK6FLAB.

The dynamic nature of your shack

Sat, 04/10/2021 - 12:00
Foundations of Amateur Radio

If you have the opportunity to build your shack, it might start off as a table in the corner where you plonk down a radio, plug into nearby power and run coax to. That's pretty much how most shacks start, mine included.

For me the step of running coax was an activity that took weeks of planning and procrastination and days of climbing on the roof. After actually completing that and getting two runs of coax to my planned shack, one for HF and one for UHF and VHF, the shack building itself was pretty simple.

I had to get power to the location, but an extension lead took care of that. In the interest of space I put the power supply on the floor, a wooden floor that ensured good circulation, unlike carpet, perhaps a topic for another day, I plugged my coax into the radio, plugged in the 12 Volt power and was up and running.

Over time that space continued to grow. Looking at it right now, it has two computer monitors, a laptop, three radios, two coax switches, a keyboard, mouse, digital interface, two speakers, and a fan to cool the radio when I'm calling CQ on FT8.

I'm not a messy person, but I do like to have my tools convenient. It's not a pristine environment by any stretch, but it's orderly as shacks go. An hour ago it wasn't, actually, looking at the clock, that was four hours ago. Time flies when you're having fun.

My shack is the centre of my radio activities. I might receive a gadget from a friend to test and I'll put it on my desk ready to go. The same is true for a foot pedal that I found when looking for something else, as is the audio adaptor that I used in the desk mixer that I'm experimenting with.

Over time each of these bits and pieces accumulate on the surface.

When I noticed that my radio was running hot, or in my mind uncomfortably warm, given that I'm using 5 Watts, I decided to invest in a fan, clipped to the edge of the desk requiring yet another wire.

It's not limited to small bits. I'm testing a new radio, that comes with removable head, a microphone, cables to join those to the main body, two antenna port cables, a coax switch and a power lead with two cables.

Over time you have coax mixed with 12 Volt DC and 240 Volt AC, audio leads, USB leads, video leads, grounding wire, remote control switches, microphone leads, CAT leads and more, all running all over the place.

Making a minor change can become a big hassle, making it hard to determine what goes where, not to mention that each cable generates it's own little slice of RF, wanted or not.

The four hours I've just spent consisted of taking everything except the bolted on computer monitors off the desk and starting from scratch.

I also did this when I first added a second radio, but that was so long ago that the "system" I implemented then was unrecognisable. Doing it again today I made better use of the environment and changed some things around. I started with the 240 Volts requirements, then the coax, then 12 Volts, then audio and finally USB, using cable ties for semi-permanent things like power boards and hook and loop straps for things that move more frequently like audio wiring and video cables.

It's not perfect. I'm looking for some flexible coax patch leads, there's USB cables going every which way, the laptop keyboard isn't used, so why use a laptop, no doubt I'll discover more.

My point is that this is dynamic and every now and then it pays to spend a little while putting things back together.

My next project is to use an audio mixer to bring all the audio together in one place so I can use one headset for everything and give me the opportunity to plug in a tape recorder as my regulator suggests for monitoring emergency communications, though I might have to come up with something a little less 1980 for the actual recording.

If you're going to do this, move the desk at least a meter from the wall so you can get at the back of your shack, you can thank me later.

I'm Onno VK6FLAB

When you just have to try things ...

Sat, 04/03/2021 - 12:00
Foundations of Amateur Radio

A little while ago I was gifted a new radio, well, new to me. A Kenwood TS-480HX. It's an all mode HF transceiver with 6m. Does 200 Watts, but you know me, I'm into QRP, low power, so I first had to figure out how to dial the transmitter down to 5 Watts and that was after figuring out how to feed the dual power supplies from one source and have the fuses work as expected.

When I received the radio, I took stock of all the bits that it was packed with, all complete, all the accessories, even the user manual was laminated. The previous owner, Walter VK6BCP (SK) whom I never met was an amateur after my own heart. I've talked about how he meticulously documented his alterations to a power supply for example.

Previously I've taken this radio on holidays to operate portable in a field day. The experience was underwhelming, in that I didn't hear anyone and nobody responded to my CQ calls. At the time I put it down to a poor antenna and unfamiliarity with the radio, despite reading the manual, well, at least scanning it.

Today I finally set some time aside to do some more testing. I decided that the first step would be to actually set it up in my shack, next to my trusty Yaesu FT-857d and see how it performs in comparison.

So, I plugged everything in, found a coax switch so I could switch the antenna between the two radios and learned that the audio connector that I've been using for digital modes on the Yaesu is actually compatible with the Kenwood. Now I need to make another adaptor for this radio, but in the meantime I can move the audio plug between radios when I swap.

In doing this I learnt a few things.

One is that there's plenty of scope for things to break.

For example, I was reaching over the desk to plug a connector into the coax switch when I leaned on the keyboard and touched the space bar. This caused the radio that I was working on to start its tuning cycle without an antenna connected. Fortunately I was using 5 Watts and I caught it within seconds, so no white smoke this time around.

It does remind me to turn off the radio when fiddling with connectors though. I'm embarrassed to report that I thought I'd learnt that lesson already, nothing like a refresher course in transmitter safety and dumb things not to do in the shack.

Then there was the thing about using remote control. In my naivety I thought that the connector that the Yaesu uses for computer control is also used on the Kenwood. Turns out that it isn't. Fortunately I read the manual before plugging that in.

The Yaesu has a specific digital mode with individual gain and filter characteristics, which seem to be completely lacking on the Kenwood.

I'm still attempting to learn the differences in receive performance between the two. I started this process by running WSJT-X and listening to WSPR or Weak Signal Propagation Reports and testing how both radios decode things. I cannot yet do this side-by-side, but for now I can swap and see signals coming in on either radio.

This is not the first time I've put a different radio on my desk to see how it works and it's not going to be the last time. What I'm looking to achieve is to swap over from the Yaesu to the Kenwood in my shack, so I can put the Yaesu back in the car and have a mobile shack operating again because I have to admit, I do miss that.

What kinds of testing regimes to you have when you're trying out a new radio? I'd love to hear your thoughts. My email address as always is [email protected]

I'm Onno VK6FLAB

Portable experiences ...

Sat, 03/27/2021 - 12:00
Foundations of Amateur Radio

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

The remote edge...

Sat, 03/20/2021 - 12:00
Foundations of Amateur Radio

The landscape of remotely operated amateur radio is changing by the day. Once the territory of home brew DTMF decoders and remote controlled radio links, now more often than not it's a Raspberry Pi with an internet connection, or some variation on that.

Before I continue, I must point out that amateur regulations vary widely around the globe, especially in this area. It appears mostly due to the rapidly changing nature of remotely operated radios.

For example, most, if not all software defined radios are technically remotely operated. You run software on your computer, the radio is connected to a network, you twiddle a setting on your computer and the radio responds. The computer is not part of the radio, but without it there's not much radio to be had. There's no need for both to be in the same room, let alone the same building.

Similarly, a Kenwood TS-480 and a Yaesu FT-857d are both radios that have a removable face with knobs and a display. The main body of the radio is a nondescript box with sockets for power and antenna, connected to the face essentially via a serial cable that can be a few centimetres long, or a few meters. There's solutions like RemoteRig that replace this serial cable with a virtual cable, allowing you to put the face in one location and the body in a different one, connected to each other across the internet.

With the introduction of Starlink internet, a low earth orbit satellite based network, a connection to the internet can be made anywhere on earth, making it possible to have your station sitting somewhere far away from interference, powered by batteries and solar panels and connected to the internet. You might not even need to go to satellite based internet, the mobile phone network in many places is often more than sufficient for making such a station viable.

If you're a member of a radio club, you might consider your club station. Often this station is the work of many volunteer years effort with multiple radios, antennas, filters and the like and often it sits idle most of the time, only getting fired up during club meetings or the weekend. What if you connected that station to the internet and offered it as a service to your members?

Depending on license requirements, you might consider amateurs who have limited ability to build a shack but would love to be on air making noise. A remote club shack might be just the ticket for getting them on air. It could even become an income stream for your club.

You might be able to offer access to trainees, or let them monitor the station without transmit ability whilst they're preparing for their license, or you might operate a 48 hour contest in shifts, all using the same transmitter, but from the comfort of your home.

The landscape is full of different solutions, like RemoteRig, which I've already mentioned, RigPi Remote Station Server is a tiny computer that controls your radio and allows you access via a web browser or remote desktop connection. There's Remote Hams, a ready made solution for putting your shack on air with access control and remote management. You can connect specific radios, like the Elecraft K3 Remote System, or a Flex Radio Maestro, there's even web browser remote control projects like Universal Ham Radio Remote by Oliver F4HTB, each making it possible to get on air and make noise using a radio in a different location across the internet.

All of the solutions I've named make it possible to fully use your radio, that means CW, SSB, FM, antenna control and the like. You can use it for FT8 or RTTY, the choice is yours.

The interface might be the face of your radio, a special console, computer, phone or a tablet and you can operate it wherever and whenever the mood takes you.

No longer do you need to have a shack in your home with coax snaking through the walls to an antenna whilst dodging the local authorities, or fighting the engine noise from your car. You can make the ultimate shack anywhere without taking up space in your home or car.

One final comment. This is a moving feast. The level of functionality is increasing by the day. For me this journey started with a steel toolbox in my garage with a radio inside it and coax running from the box to my antenna. I have operated my radio and hosted my weekly net like this. The radio in the garage, me in my office connected via Wi-Fi over a virtual serial cable. You don't need to start this in the middle of nowhere, six hours drive over the back roads to fix a problem, you can start this project today at home.

Where on this journey are you and what issues have you come up against? Let me know. My address as always is [email protected]

I'm Onno VK6FLAB

Making observations

Sat, 03/13/2021 - 11:00
Foundations of Amateur Radio

Amateur radio is an environment for infinite possibilities. I've spoken about the way that contacts can happen, seemingly out of the blue, how propagation has so many variables it's hard to predict what will happen at any given moment. During a contest you might scan up and down the bands looking for an elusive multiplier, a contact that's worth extra points, or a missing DXCC country, in your quest to contact a hundred or more. It's easy to get swept away in the excitement and disappointment that comes with success and failure.

I'm mentioning this because it's pretty much how many people in our community go about their hobby, me included.

I've likened making a contact to fishing, taking your time to get the rhythm of the other station, understanding that there's a human at the other end. Taking stock of what they're hearing, which stations they're responding to, how they respond and if they give out hints about making a successful contact with them.

The other day I came across a request to decode some Morse on an image showing long and short lines joined together in some form to serve an artistic purpose. Others pointed out that this wasn't Morse. I took an extra moment to point out that Morse had four individual attributes. It has a dit, a dah, a spacing between the letters and a spacing between the words, and since this image didn't have that it couldn't be Morse code. A few days later it occurred to me that I hadn't been paying attention. Morse actually has five attributes, it also has a spacing between each tone. I updated my answer and began to think about this interaction.

It's not the first time that I've stopped to consider what's happening.

For example, if I change bands on FT8, a digital mode that is very helpful for determining current propagation, I have a look at the level of activity. I'm generally not in a hurry, so I tend to leave it on the same band for a while, sometimes an hour, sometimes less, sometimes more. If the band is in full flight with every slot filled, it's easy to tick the "CQ Only" box and hide all the noise, or rather extra messages that form the exchange, but sometimes that noise has a whole lot of interesting information.

You can determine if one of the stations calling CQ is actually answering anyone or if they're just an alligator, all mouth, no ears. You can see individual people attempting to get each other's attention, making a local or a long distance contact. You can type in an interesting grid locator that accompanies most CQ calls and see just how far it is from you and in which direction.

I will also point out that using FT8 to observe a so-called dead band can be just as illustrative. It allows you to see signals in the waterfall, it decodes things that are barely visible and it will give you a feel for how your station at that location on that band at that time is performing in real-time. For example, it showed me that the squelch on my radio was turned on and blocking any chance of receiving weak signals, something that I wouldn't have noticed if I hadn't taken the time to observe.

Another example. During a contest I often take some time to listen to a pile-up that surrounds a massive station to see what stations I can hear, who is coming in strong and who is coming in weak. I keep a mental or actual note of what cracks the S-meter with an indication of signal strength and what only turns up as audio, perfectly readable, but not exciting the needle in any way. I might not speak with any of those stations, but I know that there are stations in a particular location that I can hear.

It's easy to get swept up in all this massive excitement that is our hobby, but sometimes it pays off to take a breath, to wait a moment, to take a look and have a listen to learn the lay of the land and understand what is happening and consider the implications. Within that moment of calm you might find an unexpected jewel in the rough. That's for example how I managed a contact with South Sudan several years ago during a massive pile-up in a club station during a contest.

I'd love to hear what you have stumbled upon serendipitously like that. You can always get in touch, [email protected] is my address.

I'm Onno VK6FLAB

Word of the day: software

Sat, 03/06/2021 - 11:00
Foundations of Amateur Radio

Every community has its own language. As a member of that community you learn the words, their meaning and their appropriate use. For example, the combination of words "Single Side Band" have a specific meaning inside amateur radio. Outside of radio, those same words are random words with no relationship.

Sometimes a term like "FM" can be heard across many communities with similar understanding, though not identical.

It gets tricky when a word is used widely but doesn't have a common understanding at all. A word like "software" for example.

A question you might hear in amateur radio is: "Can I buy a software defined radio or SDR that has digital modes built-in?"

It's a perfectly reasonable question, the radio runs software, the digital modes are software, so the answer is obvious, right?

What about: "Can the hundred or more computers in my car play Solitaire?"

Aside from the perhaps unexpected fact that your car has computers on board, you most likely know the answer to that. No, since the computers are specialised for different tasks - and if you're driving a Tesla right now, yes, you can play Solitaire, but I'd recommend that you keep your eyes on the road instead.

My point is that not all software is created equal.

The software inside an SDR is essentially doing signal processing, often by several components, each running software, transforming an antenna signal into something, that can be used somewhere else, likely sound.

The applications WSJT-X and fldigi, both software, use a computer running Linux, MacOS or Windows, software, to decode and encode digital modes while providing a way for you to interact with it. Software running on software.

You might well argue that we should be running applications like that directly on our radio and on the face of it that sounds perfectly reasonable, except that to achieve that, you'd also need to build a system to install and update different types of applications, so you could run SSTV, APRS, RTTY, PSK31, FT8 or any of the other hundreds of digital modes and new ones as they are developed.

If you did that, you'd also have to provide a way to manage the operating system, to connect to the Internet and provide security. You'd need to develop a user-interface, perhaps a keyboard and mouse solution, a screen, etc.

Before long you'll have developed a whole computing infrastructure, much like the one we already have in the form of the computer on your desk or the phone in your pocket.

Computers are getting faster and faster every day. This allows for the software on them to become more and more complex. The inter-dependencies are increasing by the second, but that doesn't mean that specialisation isn't useful.

A software defined radio likely has a Field Programmable Gate Array, an FPGA on-board that is great at processing data in streams. It too runs software. Your microwave is running software, as is your television, your smart-watch, your battery charger, the gearbox in your car and your electric tooth brush.

Making a distinction between the various types of software is helpful to understand what is possible and what is not. Being a computer nerd, I must point out that I've only barely scratched the surface of software here, in-case you're curious, microcode, firmware, hardware abstraction, the rabbit hole goes very deep.

Not all software is created equal and every now and then it's a good idea to remember that when you talk about a word in one community, it might mean a completely different thing in another and sometimes the distinction is significant.

As for having an SDR that runs WSPR, no. You can transmit from a computer though, but that's a whole other thing.

I'm Onno VK6FLAB

How many hops in a jump?

Sat, 02/27/2021 - 11:00
Foundations of Amateur Radio

Amateur radio lives and dies with the ionosphere. It's drilled into you when you get your license, it's talked about endlessly, the sun impacts on it, life is bad when the solar cycle is low and great when it's not. There's sun spots, solar K and A indices, flux, different ionosperic bands and tools online that help you predict what's possible and how likely it is depending on the time of day, the frequency, your location and the curent state of the sun. If that's not enough, the geomagnetic field splits a radio wave in the ionosphere into two separate components, ordinary and extraordinary waves.

All that complexity aside, there's at least one thing we can all agree on. A radio wave can travel from your station, bounce off the ionosphere, come back to earth and do it again. This is known as a hop or a skip. If conditions are right, you can hop all the way around the globe.

I wanted to know how big a hop might be. If you know that it's a certain distance, then you can figure out if you can talk to a particular station or not, because the hop might be on the earth, or it might be in the ionosphere. Simple enough right?

My initial research unearthed the idea that a hop was 4000 km. So, if you were attempting to talk to a station at 2000 km or at 6000 km you couldn't do that with a hop of 4000 km.

If you've been on HF, we both know that's not the case.

If you need proof, which you really should be asking for, you should check out what the propagation looks like for any FT8 station, or any WSPR beacon over time and you'll notice that it's not 4000 km.

Just like the crazy network of interacting parameters associated with propagation, the distance of a hop can vary, not a little, but a lot.

In 1962, in the Journal of Geophysical Research D.B. Muldrew and R.G. Maliphant contributed an article titled: "Long-Distance One-Hop Ionospheric Radio-Wave Propagation". They found that in temperate regions such a hop might be 7500 km and in equatorial regions even 10,000 km.

I'm mentioning this because this was based on observations and measurements.

They used frequency sweeps from 2 to 49 MHz though they called them Mega Cycles, using 100 kHz per second, that is, over the duration of a second, the frequency changed by 100 kHz, so each sweep took nearly 8 minutes using only 15 kilowatts, so substantial gear, not to mention expense and availability.

Oh, computers, yes, they used those too. A three tonne behemoth called an IBM 650, mind you, that's only the base unit, consisting of a card reader, power supply and a console holding a magnetic drum unit.

You know I'm going somewhere with this right?

Today, you can do the same measurements with a $5 computer and a $20 receiver. For a transmitter, any HF capable radio will do the trick, though you might not be transmitting long if you stray outside the amateur bands. For power, 5 Watts is plenty to get the job done.

My point is that there is a debate around the future of our hobby and why modes like FT8 are such a controversial topic in some communities.

I'm here to point out that since that publication in 1962 our hobby has made some progress and we can improve on the work done by people who came before us. We could build a glob-spanning real-time propagation visualisation tool, we already have the data and modes like FT8 keep feeding in more.

If you're inclined, you could even make such a plot in real-time for your own station.

So, how long is a hop?

You'll just have to find out.

I'm Onno VK6FLAB

You Can't Always Get What You Want

Sat, 02/20/2021 - 11:00
Foundations of Amateur Radio

One of the things about amateur radio that I find intensely fascinating and to be honest sometimes just as frustrating, is that you don't know what the outcome of an experiment might be at any one time. Not because you cannot control the experiment, or because you don't know what you're doing, but because the number of variables involved in most meaningful amateur radio experiments is pretty much infinite.

I've spoken about this before, the idea that if you were to make a simple dipole antenna and fold the ends on each other, you'd have infinite variation in antennas with just a so-called simple antenna, since you can vary the shape of it in an unending variety of ways.

The other day I was doing an experiment. An amateur radio one to be sure, but I was doing this within the realm of computing. I have been playing with digital modes for some time now and along the way shared some of what I've learnt. It occurred to me that I've been assuming that if you had the chance to follow along, you'd have access to the required hardware, simple enough, a $20 RTL-SDR dongle, but none-the-less, extra hardware.

What might happen if you rule out that dongle and instead used a web-based receiver like WebSDR, or KiwiSDR, or any number of other such sites where you can pretty much tune to any band and frequency and see what's going on at a particular antenna location.

For one it might allow you to decode something like APRS remotely, or decode an FT8 signal, perhaps even your own FT8 signal. Unfortunately most, if not all, of those sites include only the bare bones decoders for things like CW, AM, SSB and FM. After that you're pretty much on your own.

You could do some funky stuff with a web-browser, linking it via some mechanism to the tool you use to actually decode the sound and there's some examples of that around, none that I really warmed to, since it requires that I open a web browser, do the mouse-clicky thing and then set-up some audio processing stuff.

What if I wanted to figure out where the ISS was right now and wanted to listen to a receiver that was within the reception range of the ISS as it passed overhead, and automatically updated the receiver in real time as the ISS was orbiting the earth?

For that to happen you'd need something like a command-line tool that could connect to something like a KiwiSDR, tune to the right frequency and extract the raw data that you could then decode with something appropriate.

Turns out that I'm not the first person to think of this. There's even a project that outlines the idea of following a satellite, but it hasn't moved anywhere.

There's also a project that is a command-line client for web-based KiwiSDR sites, but after spending some quality time with it and its 25 clones on github, I'm not yet at the point where this will work. Mainly because the original author made a design decision to record data to a file with a specific name and any clone I've found thus far only allows you to define what name to use. None so far actually appear to send their stream to something that can be processed in real time.

Of course I could record a few minutes of data and process that, but then I'd have to deal with overlap, missing data, data that spans two files and a whole host of other issues, getting me further and further away of what I was trying to do, make a simple web-based audio stream digital mode decoder.

As the Rolling Stones put it, "You Can't Always Get What You Want"

And to me this sums up our hobby in a nutshell. When you call CQ, or go portable, or test an antenna, or attempt to build something new, there's going to be setbacks and unexpected hurdles.

I think that it is important to remember that amateur radio isn't finished, it's not turn-key, no matter how much that appeals, you cannot find a one size fits all solution for anything, not now, not yesterday and not tomorrow.

This hobby is always going to test boundaries, not only of physics, but your boundaries. It's after all one giant experiment.

So, next time you don't get what you want, you might try something you find, and get what you need.

Also, apologies to Keith Richards and Mick Jagger for butchering their words, a rockstar I am not.

I'm Onno VK6FLAB

Running out of things to do ...

Sat, 02/13/2021 - 11:00
Foundations of Amateur Radio

So, there's nothing on TV, the bands are dead, nobody is answering your CQ, you're bored and it's all too hard. You've run out of things to try, there's only so many different ways to use the radio and it's all too much.

I mean, you've only got CW, AM, SSB, FM, there's Upper and Lower Side-band, then there's RTTY, the all too popular FT8, then there's WSPR, but then you run out of things. I mean, right?

What about PSK31, SSTV, then there's AMTOR, Hellschreiber, Clover, Olivia, Thor, MFSK, Contestia, the long time favourites of Echolink and IRLP, not to forget Fusion, DMR, D-STAR, AllStar, BrandMeister or APRS.

So far I've mentioned about 20 modes, picked at random, some from the list of modes that the software Fldigi supports. Some of these don't even show up on the Signal Wiki which has a list of about 70 amateur modes.

With all the bands you have available, there's plenty of different things to play with. All. The. Time.

There's contests for many of them, so once you've got it working, you can see how well you go.

Over the past year I've been experimenting with a friend with various modes, some more successful than others. I'm mentioning this because it's not difficult to get started. Seriously, it's not.

The most important part of this whole experiment is getting your computer to talk to your radio. If you have FT8 already working you have all the hardware in place. To make the software work, you can't go past installing Fldigi. As a tool it works a lot like what you're familiar with. You'll see a band-scope, a list of frequencies and a list of decodes. It's one of many programs that can decode and generate a multitude of amateur digital modes.

If this is all completely new to you, don't be alarmed.

There are essentially two types of connections between your computer and your radio. The first one is audio, the second is control. For this to work well, both these need to be two-way, so you can both decode the audio that the radio receives and generate audio that the radio can transmit. The same is true for the control connection. You need to be able to set the transmit frequency and the mode and you need to be able to read the current state of the radio, if only to toggle the transmitter on-and-off. If you already have CAT control working, that's one half done.

I've spoken with plenty of amateurs who are reluctant to do any of this. If this is you, don't be afraid. It's like the first time you keyed up you radio. Remember the excitement? You can relive that experience, no matter how long you've been an amateur.

Depending on the age of your radio, you might find that there is only one physical connection between your computer and the radio, either using USB or even Ethernet. You'll find that your computer will still need to deal with the two types of information separately.

Notice that I've not talked about what kind of operating system you need to be running. I use and prefer Linux, but you can do this on any operating system, even using a mobile phone if that takes your fancy.

Getting on air and making noise using your microphone is one option, but doing this using computer control will open you to scores of new adventures.

I will add some words of caution here.

In general, especially using digital modes, less is more. If you drive the audio too high you'll splatter all over the place and nobody will hear you, well, actually, everyone will, but nobody will be able to talk to you because they won't be able to decode it. If the ALC on your radio is active, you're too loud. WSJT-X, the tool for modes like FT8 and WSPR, has a really easy way of ensuring that your levels are right, so if you've not done anything yet, start there.

Another issue is signal isolation. What I mean by that is you blowing up your computer because the RF travelled unexpectedly back up the serial or audio cable and caused all manner of grief. You can get all fancy with optical isolation and at some point you should, but until then, dial the power down to QRP levels, 5 Watts, and you'll be fine.

A third issue that was likely covered during your licensing is the duty cycle. It's the amount of time that your radio is transmitting continuously as compared to receiving only. For some modes, like WSPR for example, you'll be transmitting for a full 2 minutes at 100%, so you'll be working your radio hard. Even harder might unexpectedly be using FT8, which transmits in 15 second bursts every 15 seconds, so there may not be enough time for your radio to cool down. Investing in a fan is a good plan, but being aware of the issue will go a long way to keeping the magic smoke inside your radio.

I'm sure that you have plenty of questions after all that.

You can ask your friends, or drop me an email, [email protected] and I'll be happy to point you in the right direction.

Next time there's nothing good on TV, get on air and make some digital noise!

I'm Onno VK6FLAB

What's in a prediction?

Sat, 02/06/2021 - 11:00
Foundations of Amateur Radio

Over the past little while I've been experimenting with various tools that decode radio signals. For some of those tools the signals come from space. Equipment in space is moving all the time, which means that the thing you want to hear isn't always in range.

For example.

The International Space Station or ISS has a typical orbit of 90 minutes. Several times a day there's a pass. That means that it's somewhere within receiving range of my station. It might be very close to the horizon and only visible for a few seconds, or it might be directly overhead and visible for 10 minutes. If it's transmitting APRS on a particular frequency, it can be decoded using something like multimon-ng. If it's transmitting Slow Scan TV, qsstv can do the decoding. I've done this and I must say, it's exciting to see a picture come in line-by-line, highly recommended.

The National Oceanic and Atmospheric Administration or NOAA, has a fleet of satellites in a polar orbit that lasts about 102 minutes and they're overhead at least every 12 hours. You can use something like noaa-apt to decode the images coming from the various weather satellites, or a python script and I'll talk about that at some point.

There is a growing cloud of cube satellites with interesting telemetry. They're in all kinds of orbits and you can attempt to receive data from each one as it's in sight.

Keeping track of what's where and when is a full time job for plenty of people. As a radio amateur I'm happy to defer to the experts who tell me where a piece of equipment is and when I'm likely to be able to receive a radio signal from the transmitter I'm interested in.

Previously I've mentioned in passing a tool called gpredict that does this heavy lifting for me. It presents a map of the world and shows what's visible at my location and when the next acquisition of signal for a particular satellite might occur. It talks to the internet to download the latest orbital information. It also has the ability to control a rotator to point your antenna, not that I have one, and it can update the transmit and receive frequency of your radio to compensate for the Doppler effect that changes the observed frequency as a satellite passes overhead. All this works with a graphical user-interface, that is to say, you have a screen that you're looking at and can click on.

Whilst running gpredict, you can simultaneously launch the appropriate decoding tool for the signal that you're trying to receive. If you have a powerful enough computer, you can run multiple decoding tools together. You'll have separate windows for controlling the radio and antenna, for decoding APRS, SSTV, NOAA and if you're wanting to do sunrise and sunset propagation testing using WSPR, you can also run WSJT-X or any other decoder you're interested in.

There are some implications associated with doing this, apart from needing a big enough screen, needing considerable computing power and burning electricity for no good reason, the signal that comes in from your radio will be fed to all the decoders at the same time and all of them will attempt to decode the signal, even when you know that this serves no purpose. That's fine if you don't know what you're listening to, but most of the time you know exactly what it is, even if the software doesn't.

Manually launching and quitting decoders is one option, but what if the next ISS pass is at 3am?

Aside from the computing requirements, so far this works fine with a standard analogue radio like my Yaesu FT-857d. The only limitation is that you can only receive one station at a time.

If you replace the analogue radio with an RTL-SDR dongle, you gain the ability to record and decode simultaneous stations within about 2.4 MHz of each other.

Another option is to use an ADALM Pluto and as long as the stations are within 20 MHz of each other, you can record and decode their signals. If you're not familiar with a Pluto, it's essentially a computer, receiver and transmitter, all in a little box, the size of a pack of cards.

This is where it gets interesting.

The Pluto doesn't have a screen, or a keyboard for that matter, but it's a computer. It runs Linux and you can run decoders on it. I've done this with ADS-B signals using a tool called dump1090. You'll find it on my GitHub page.

One of the sticking points in decoding signals from space was the ability to predict when a satellite pass occurs without requiring a computer screen. Thanks to a command-line tool called "predict", written by John, KD2BD and others I've now discovered a way to achieve that. My efforts are not quite at the point of show-and-tell, but I've got a Docker container that's building and running predict on its own and using a little bash script it's telling me when the ISS is overhead. You'll find that on GitHub as well.

My next challenge is to do some automated decoding of actual space signals. I'm going to start with the ISS, predict and multimon-ng. I'll let you know how I go.

What space signals are you interested in?

I'm Onno VK6FLAB

Changing of the guard ...

Sat, 01/30/2021 - 11:00
Foundations of Amateur Radio

When you begin your journey as a radio amateur you're introduced to the concept of a mode.

A mode is a catch-all phrase that describes a way of encoding information into radio signals.

Even if you're not familiar with amateur radio, you've come across modes, although you might not have known at the time.

When you tune to the AM band, you're picking a set of frequencies, but also a mode, the AM mode. When you tune to the FM band, you do a similar thing, set of frequencies, different mode, FM. The same is true when you turn on your satellite TV receiver, you're likely using a mode called DVB-S. For digital TV, the mode is likely DVB-T and for digital radio it's something like DAB or DAB+.

Even when you use your mobile phone it too is using a mode, be it CDMA, GSM, LTE and plenty of others.

Each of these modes is shared within the community so that equipment can exchange information. Initially many of these modes were built around voice communication, but increasingly, even the basic mobile phone modes, are built around data. Today, even if you're talking on your phone, the actual information being exchanged using radio is of a digital nature.

Most of these modes are pretty static. That's not to say that they don't evolve, but the speed at which that happens is pretty sedate.

In contrast, a mode like Wi-Fi has seen the explosion of different versions. During the first 20 years there were about 19 different versions of Wi-Fi. You'll recognise them as 802.11a, b, g, j, y, n, p, ad, ac and plenty more.

I mention Wi-Fi to illustrate just how frustrating changing a mode is for the end-user. You buy a gadget, but it's not compatible with the particular Wi-Fi mode that the rest of your gear is using.

It's pretty much the only end-user facing mode that changes so often as to make it hard to keep up. As bad as that might be, there is coordination happening with standards bodies involved making it possible to purchase the latest Wi-Fi equipment from a multitude of manufacturers.

In amateur radio there are amateur specific modes, like RTTY, PSK31, even CW is a mode. And just like with Wi-Fi, they evolve. There's RTTY-45, RTTY-50 and RTTY-75 Wide and Narrow, when you might have thought that there was only one RTTY. The FLDIGI software supports 18 different Olivia modes out of the box which haven't changed for a decade or so.

The speed of the evolution of Olivia is slow. The speed of the evolution of RTTY is slower still, CW is not moving at all. At the other end new amateur modes are being developed daily.

The JT modes for example are by comparison evolving at breakneck speed, to the point where they aren't even available in the latest versions of the software, for example FSK441, introduced in 2001 vanished at some point, superseded by a different mode, MSK144. It's hard to say exactly when this happened, I searched through 15 different releases and couldn't come up with anything more definitive than the first mention of MSK144 in v1.7.0, apparently released in 2015.

My point is that in amateur radio terms there are modes that are not changing at all and modes that are changing so fast that research is being published after the mode has been depreciated. Mike, WB2FKO published his research "Meteor scatter communication with very short pings" comparing the two modes FSK441 and MSK144 in September 2020, it makes for interesting reading.

There are parallels between the introduction of computing and the process of archiving. The early 1980's saw a proliferation of hardware, software, books and processes that exploded into the community. With that came a phenomenon that lasted at least a decade, if not longer, where archives of these items don't exist because nobody thought to keep them. Floppy discs thrown out, books shredded, magazines discarded, knowledge lost.

It didn't just happen in the 1980's. Much of the information that landed man on the moon is lost. We cannot today build a Saturn V rocket with all the support systems needed to land on the moon from scratch, even if we wanted to. We have lost manufacturing processes, the ability to decode magnetic tapes and lost the people who did the work through retirement and death, not to mention company collapses and mergers.

Today we're in the middle of a golden age of radio modes. Each new mode with more features and performance. In reality this means that your radio that came with CW, AM, FM and SSB will continue to work, but if it came with a specialised mode like FSK441, you're likely to run out of friends to communicate with when the mode is depreciated in favour of something new.

In my opinion, Open Source software and hardware is vitally important in this fast moving field and if we're not careful we will repeat history and lose the knowledge and skill won through perseverance and determination due to lack of documentation or depreciation by a supplier.

When did you last document what you did? What will happen to that when you too become a silent key?

I'm Onno VK6FLAB

The Vagabond HAM

Sat, 01/23/2021 - 11:00
Foundations of Amateur Radio

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.