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Recently I discussed the idea of listening to the radio spectrum across the internet for the purposes of getting signal into your shack when radios, or in my case, antennas are causing you challenges.

I continued to explore and discovered a project by Jacobo EA1ITI, called "radioreceiver". Behind that unassuming name lies a tool born in 2014, that allows you to plug an RTL-SDR dongle into your computer, open up your web-browser, and listen to the radio signals that your dongle can receive.

In case you're unfamiliar, an RTL-SDR dongle is a small USB device, looks a lot like a USB thumb drive, jump drive, data stick or flash drive, basically a hunk of plastic with a USB connector on it. An RTL-SDR dongle generally also has some form of antenna connector. It's typically sold as a digital radio and digital television receiver, but websites like rtl-sdr.com sell purpose built ones. They can be found starting at about $15.

I realise that this is using a local receiver, with a local antenn

Foundations of Amateur Radio

One of the many challenges associated with being a radio amateur is actually being able to listen to weak signals. If you're like me and more than half the planet, you live in an urban area, which comes with the benefits and pitfalls of having neighbours.

From a radio perspective, there's plenty of noise that drowns out weak signals, so more and more amateurs are finding new and interesting ways to deal with this.

Over the years I've talked plenty about so-called web-sdr, or internet accessible software defined radios. Essentially a radio receiver, preferably in a radio quiet area, hooked up to some software that allows you to listen in using a web browser. There's thousands of internet based services across the globe, the most popular of those are websdr.org and kiwisdr.com.

As a new amateur you might have visited one or more of these and tuned around to listen to various radio stations and QSOs or contacts between amateurs, on bands that you can't acc

Every single radio amateur has come to this hobby with an itch to scratch. Time and again I've seen amateurs around me pursue that particular purpose, only to come out the other end with a look of bewilderment writ large across their face. For some amateurs it means the end of their involvement in the hobby, for others it starts a new journey into the unknown.

One of the ways we explore our community is by travelling out of our shack into the big outdoors in whatever form that takes. Popular activities include setting up a radio in a location and talking to others, known colloquially as an "activation". We do this all over the planet. Perhaps the most recognisable of these is IOTA, or Islands On The Air, where a station is erected on an island and contacts are made. As amateurs we cannot help ourselves and seem to have an insatiable need to measure our prowess. We do this by counting how many contacts, callsigns, countries, grid-squares, or in this case, islands, we've managed to put

Recently I came across a series of strident posts about the injustice associated with a non-amateur service using the 70cm band. Complete with links to discussions, spectrum plots, angst and even incoherent outrage, all related to the notion that whomever "allowed" this user to transmit on this band was clearly incompetent.

Except, that this is probably not the case, or the full story.

So, what's going on and why are people incensed?

This all started at least six years ago. Since then AST SpaceMobile has deployed seven low Earth orbit satellites and used the 70cm band to communicate with them. Although in the trial phase, there's plans for an additional 243 satellites, and there's at least one other company playing in the same space, Atmos Space Cargo.

The outcry from amateurs is around the commercial use of "their" 70cm amateur band. It's an emotional statement, but what is the reality?

Before I dig in, let's set some terms. Radio frequencies are globally coordinated because elec

In the community of radio amateurs scattered around the planet we have a habit of getting together with others to have fun in whatever shape that takes. The obvious ones are HAMfests, car boot sales, raffles and other amateur adjacent pursuits, but we also do things like licence training, weekly on-air nets, contesting, portable activations, climbing mountains, or hills, setting-up in parks, or lighthouses, we set-up on a field day, just for fun, and find excuses, sorry, reasons, for any number of other activities.

Some of these are solitary affairs, but many are best enjoyed shared with multiple friends, both old and new ones. Having been a member of this community since 2010 I've come to observe an aspect of this community that is odd, to say the least.

We organise all these events, but rarely promote it beyond a single email to three people, if that. It's almost as-if the average organiser thinks that their event permeates the community by magic osmosis.

Even if there is any form

Recently I was given some radio data captured on the 40m band. Using a piece of software called "Universal Radio Hacker", I attempted to decode it. At the time I thought that this might be Morse code, since then I've been told by someone who has been using Morse longer than I've been alive, that it isn't.

I shared the data on my VK6FLAB GitHub repository where you can download it and see what you learn, and perhaps repeat what I did, or better still, improve on it.

Over the years I've talked a little about how Software Defined Radio or SDR works, essentially it's a glorified Analogue to Digital converter, much like the sound card in your computer, which does the same, albeit at a much lower frequency. As it happens, you can represent the signal that comes into your radio antenna as a series of values. Essentially, the stronger the signal, the bigger the number, the weaker the signal, the lower the number.

Let's talk about the characteristics of this signal. It consists of two parall

Recently I was helping a friend erect their newly refurbished multi-band antenna and during the process we discussed the notion of tuning an antenna that's high in the air. They made a curious response, in that they'd tuned the antenna on the ground before we started.

I asked how this would work, since as I understand the process, this changes things once it gets in the air. They assured me that while the actual SWR might change, the frequencies at which it was resonant would not.

This was news to me because I've been putting off erecting my own multi-band 6BTV antenna mainly because I didn't really want to face having to erect it, tune it, lower it, modify the elements, erect it, tune it, etc., all whilst standing on the steel roof of my patio. Would this phenomenon be true for my antenna?

It occurred to me that I could test this idea, not only for my antenna, but for other antennas as well. In my minds-eye, I saw a video displaying the pertinent attributes of an antenna, SWR, gain

Just over a year ago, the ARRL, the American Radio Relay League, the peak body for amateur radio in the United States and one of the oldest of such organisations, experienced an incident.

During the weeks following, the ARRL was tight-lipped about the extent of the incident and most amateurs only really noticed that services were off-line or slow to respond. After months of delay and disinformation, the ARRL finally revealed that it was the subject of a ransomware attack and that it had paid a million dollar ransom. It went on to blame the authorities for its silence.

Mind you, it didn't tell me personally, it made public statements on its website. Similarly when I specifically contacted the ARRL to discover what information of mine it held, and what the status of that information was, the ARRL responded that I should refer to its public statements. It continued to state that my information was not compromised, since it only lived in LoTW, the Logbook of The World, the system it uses

Foundations of Amateur Radio

The other day Randall, VK6WR, encouraged me to get on-air. He described it like this:

"There is a mystery signal on 40m that you can try your new Universal Radio Hacker skills on. It appears to be a FSK signal separated by 7kHz with the two signals at 7.0615 and 7.0685 MHz. Each of them on their own sounds a bit like a Morse signal, but my CW decoder decodes junk. But if you can see it on a spectrum scope, it is clearly FSK because either one of them is on at any time."

He went on to say: "You'll need an SDR to receive the signal given the separation, but could be a fun investigation!"

Having just discovered "Universal Radio Hacker", a tool that can help you decode radio signals, that sounded like something I'd love to have a go at. Unfortunately, after the demise of my main workstation last year, my current set-up doesn't allow me to do such recordings, but Randall, ever the gentleman, provided a recording of the signal.

He writes: "This was captured

The other day I was discussing with a fellow amateur the increased frustration my mobile phone provider was inflicting. We hit on the idea of figuring out if other providers would fit the bill and how we could determine if their coverage would suit our needs. Aside from using an old mobile phone, I suggested that using a $25 RTL-SDR dongle would provide a way to record mobile phone cell site beacons from the various mobile networks to map what signal levels we might find.

To that end, I discovered a tool called LTE-Cell-Scanner by Xianjun BH1RXH. Forked from the original project by James Peroulas, it allows you to use simple hardware to scan for LTE Cells used by mobile phone networks. James points out on his site that this tool can also be used to calibrate an RTL-SDR receiver's oscillator, since an LTE downlink centre frequency is stable to within 50 Parts Per Billion, that's 10 times more stable than my Yaesu FT-857d using a TCXO.

If this doesn't mean much, think of it as a local

The other day a fellow amateur asked me to help them with lowering their radio mast so they could do some maintenance on the antennas attached to it. This is not the first time I've been a participant in such an activity, but it was the first time I felt explicitly safe.

Don't get me wrong, on previous occasions nothing bad happened, but there was always an undertone of "what-if" and an associated anxiety. This time was different. Before we did anything, we sat down, had a cup of coffee, talked and discussed what was going to happen. After coffee we looked at specifics and discussed the process in detail. Then we prepared. Clipping cable ties, winding up loose ends, disconnecting coax, and securing a pulley to a tree. We ran a winch line, discussed distances, looked at potential snags and coax lengths and angles, considered what would happen if something unexpected might happen and discussed various safety considerations, like never walking below the mast whilst it was in its most str

The other day a report in "Amateur Radio Daily" caught my eye. Under the heading "IARU Considers Consolidation", I read that the International Amateur Radio Union, celebrating 100 years of representing our hobby, is considering significant change. Links in the report reveal a PDF document titled "IARU Consultation on Proposed Restructuring March 2025".

The document, dated 21 March, outlines the structure of the IARU, four organisations, one for each ITU Region, and one global organisation, the International Secretariat. It provides some insights on how the funding arrangements between these organisations exist and goes on to talk about how the IARU operates, including incorporation, or not, currencies, committees, priorities and other background and historic information.

All excellent. Stuff that should be public knowledge, but having spent the better part of a year reading IARU documents, this one brought several new eye opening things to the table.

The document attributes no autho

Right off the bat, let me start with a question. "What do you think you're doing?"

To give you some context, it should come as no surprise that I'm talking about amateur radio and what it is that we do, you and I, when we "do amateur radio".

Of course the answer is different for every person you ask, and it's likely to change over time. So, let's explore and fair warning, if you know me at all, you'll realise that I'll be asking more questions, so here goes.

Is this an activity that you do, for yourself, or for others? Is it a hobby, or a vocation, or something else? Do you use this as part of your life outside this community and if you do, how?

At this point I hope you're getting a sense of Deja-Vu all over again, in that I'm asking you to explore your own place in the community. I'm asking because it occurs to me that we spend an awful lot of time looking in the other direction.

How do we compare skills and knowledge against other amateurs, how does our shack compare with anothe

Around the world are thousands of associations, groups of people, clubs if you like, that represent radio amateurs. Some of those associations are anointed with a special status, that of "member society" or "peak body", which allows them to represent their country with their own governments and on the international stage to the ITU, the International Telecommunications Union, through a global organisation, the IARU, the International Amateur Radio Union.

Some of these are known across our whole community, the ARRL in the USA, the RSGB in the UK, and the WIA in Australia. Some much less so, the CRAC, the Chinese Radio Amateurs Club, or the ARSI, the Amateur Radio Society of India, for example.

In an attempt to get a deeper understanding of what distinguishes these organisations, I visited a dozen member society websites. Cultural sensibilities and aesthetics aside, the variety and sense of priority is both pleasing and astounding.

Starting close to home, the WIA, the Wireless Institu

Since becoming a licensed amateur in 2010, I have spent a good amount of time putting together my thoughts on a weekly basis about the hobby and the community surrounding amateur radio. As you might know, my interest is eclectic, some might say random, but by enlarge, I go where the unicorns appear.

Over a year ago I mentioned in passing a community called HamSCI. The label on the box is "Ham Radio Science Citizen Investigation", which gives you a sense of what this is all about. It was started by amateur radio scientists who study upper atmospheric and space physics.

More formally, the HamSCI mission is the "Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art."

If you visit the hamsci.org website, and you should, you'll discover dozens of universities and around 1,300 people, many of whom are licensed radio amateurs, who are asking questions and discovering answers that matter to more than just our amateur community.

For the

Recently I saw a social media post featuring a screenshot of some random website with pretty charts and indicators describing "current HF propagation". Aside from lacking a date, it helpfully included notations like "Solar Storm Imminent" and "Band Closed".

It made me wonder, not for the first time, what the reliability of this type of notification is. Does it actually indicate what you might expect when you get on air to make noise, is it globally relevant, is the data valid or real-time? You get the idea.

How do you determine the relationship between this pretty display and reality?

Immediately the WSPR or Weak Signal Propagation Reporter database came to mind. It's a massive collection of signal reports capturing time, band, station and other parameters, one of which is the Signal To Noise ratio or SNR.

If the number of sun spots, or a geomagnetic index change affected propagation, can we see an effect on the SNR?

Although there's close on a million records per day, I'll note i

A recent comment by a fellow amateur sparked a train of thought that made me wonder why there is a pervasive idea within our community that you need a radio transmitter and antenna to be a radio amateur, moreover that for some reason, if you don't have either, you're not a real amateur.

I suppose it's related to the often repeated trope that the internet enabled modes like Allstar Link, Echolink and even IRLP, are not real radio, despite evidence to the contrary.

Instead of fighting this weird notion, I figured I'd get on with it and find a way to play even if you don't currently have the ability to erect an antenna or key a transmitter for whatever reason.

Before I dig in, a WebSDR is a Software Defined Radio connected to the Internet. It allows a user to open a web browser, pick from a massive collection of receivers around the world and listen in. Some of these also have the ability to transmit, but more on that later.

Here's the idea.

Have you ever considered tuning to a WebSD

Over the years I've talked about different ways of using our license to transmit. I've discussed things like modes such as voice AM, FM, and SSB, and digital modes like FT8, WSPR, RTTY, FreeDV, Hellschreiber, Olivia and even Morse code.

Recently it occurred to me that there is something odd about how we do this as a community. Now that I've realised this it's hard to unsee. Let me see if I can get you to the same place of wonder.

Why is it that we as amateurs only use one such mode at a time?

Let me say that again. With all the modes we have available to us, why do we only use one mode at a time, why do we get our brain into the mindset of one activity, stop doing that in order to move to another mode?

It's weird. Amateur radio is what's called "frequency agile". What I mean by that is we are not restricted to a fixed number of channels like most, if not all other radio users. We can set our transmission frequency to whatever we want, within the restrictions imposed by our license

One of the basic aspects of being human and growing up is the process of learning. From a young age we explore our environment, play with others, have fun, fall over and bruise our knees, get up and try again. The playing aspect of this is often discussed as a way to keep things interesting. We add a competition element as an added incentive, so much so that we formaulate it into global competitions and call it sport.

As a species it might surprise you that we spend about 1% of all Gross Domestic Product on sport, compared to science, which is about 2% of Global GDP. To give you some context, Agriculture accounts for about 4%, Manufacturing is 15%, Industry is about 26%, and Services account for roughly 62%. If you noticed that this is more than 100%, take it up with the World Bank, I'm a radio amateur, not an economist.

Over the years I've explored different aspects of our chosen hobby of amateur radio. Time and again I return to experimentation, learning and having fun. Now I absol

When you join the community of radio amateurs, or when you briefly look over the shoulder of the nearest devotee, you're likely to discover that this is a hobby about a great many different ideas. Over the years I've discussed this aspect of our community repeatedly, talked about the rewards it brings you, about the camaraderie, about communication, learning, research, soldering, disaster recovery, public service, and all the other thousands of activities that this hobby represents to the world.

While all those things might be true for some, they're not true for everyone. Many amateurs get excited about antennas, some immediately, some eventually. The same can be said for all the other points of what we think of when we discuss our hobby with others.

Recently I saw a random comment on social media from a person who was having issues with their mobile phone on their property. I considered and ventured an opinion about what might be the cause and how they might go about discovering wha