Foundations Of Amateur Radio

Foundations of Amateur Radio If you've ever been in the market for a new radio, and truth be told, who isn't, you'll find yourself faced with a bewildering array of options varying from obvious to obscure and everything in between. At the obvious end of the scale are things like price, bands and transmit power and at the other end are things like Narrow Spaced Dynamic Range, which you'll find explained by Rob NC0B on his sherweng.com website where he's been publishing receiver test data for many decades. One of the more subtle options you'll need to consider are handheld, mobile or base radio. This is harder than you might think, since radios are increasing in functionality every time you wake up and if you look long enough, you'll discover that they're getting smaller at the same rate. Once upon a time you could just look at the size of a radio and define it as belonging in one or other category, but that's no longer a useful distinction. For example, my PlutoSDR is a tiny device, fits in my pocket, but t

Foundations of Amateur Radio It's an immersive effort to create an article every week, so much so, that I've only just discovered that I passed the 600 article mark some time ago. I'd open up a bottle of something celebratory if I thought it warranted the effort, but I'd rather talk about amateur radio and what I've learnt since becoming licensed in December of 2010. This hobby, this community, the activity of amateur radio keeps surprising me in unexpected and exciting ways. I know that there is a part of the community that thinks of this as a dying hobby, but with every fibre in my being I know this to be wrong. We explore, test, build and learn at every opportunity. Put any two amateurs in contact with each other, either physically or over the air and you'll soon witness an exchange of ideas, of things that bring joy, hints of the next thing and the next. The inspiration for my writing comes from all manner of places. For example, here's an opinion recently shared by someone on social media: "Basic ant

Foundations of Amateur Radio One of the many questions that new amateurs ask is, "When should I get on-air, and on what band?" The often-heard reply is just to get on-air and make some noise. As time goes by, the importance of this seems to fade in favour of using HF prediction tools. Some amateurs never venture beyond that point, relying almost exclusively on technology to determine if they should turn on their radio or not. If you search the internet for "current HF conditions", you'll end up with dozens of sites boldly claiming to provide precisely that information, some even using the label "Real-Time". You'll find instructions from countless self-proclaimed "experts" on how to read propagation conditions from their favourite site. There's even widgets that you can install on your website displaying propagation data per amateur band with helpful labels like "Band Closed" or showing conditions as "Poor", "Fair" or "Good". Some of these widgets even include an embedded time-stamp to prove just how "curren

Foundations of Amateur Radio In 2016, Daniel EA4GPZ, documented how to discover the weakest signal that could be decoded using several weak signal modes, including WSPR, or Weak Signal Propagation Reporter. This is an interesting question because as you might recall, I've been experimenting with very weak signals coming from my shack. To date, my 20 milliwatts has been heard over 13 thousand kilometres away. When you tune to a weak station you'll often hear both the station or desired signal as well as interference or background noise. The stronger the signal, the less noise you perceive. The weaker the signal, the more noise. You can express the relationship between the power of these two, the signal and the noise, as a ratio. If the power levels are the same, the so-called signal to noise ratio or SNR is 1:1. A higher ratio, like 2:1, indicates that the power of the signal is higher than the noise and a lower ratio, like 1:2 indicates that the signal is lower than the noise. If you express this ratio in

Foundations of Amateur Radio Have you ever asked yourself a question that turned out to be a rabbit hole so deep you could spend a lifetime exploring and likely never come out the other end? I did. Yesterday. What's a Volt? This came about when I started exploring how to measure the power output of my WSPR or Weak Signal Propagation Reporter beacon. According to the specifications the output level is 23 dBm or 200 milliwatts. If you read the fine print, you'll discover that the power output actually varies a little depending on which band you're on, for my specific transmitter it says that the output on the 10m band is 22 dBm, or 158 mW. That comes with a disclaimer, that there can be some variation on individual transmitters of about 1 dB. So, on 10m, my output could vary between 21 and 23 dBm, or between 125 and 200 mW. With my attenuator connected, the output could be between 12 and 20 mW, and that's assuming that my attenuator is exactly 10 dB, it's not. Measuring anything means to compare it again

Foundations of Amateur Radio Propagation, the art of getting a radio signal from one side of the globe to the other, is a funny thing. As you might know, I've been experimenting with WSPR or Weak Signal Propagation Reporter and for about a year running a beacon on 10m. Out of the box my beacon uses 200 mW to make itself heard. I couldn't leave well enough alone and I reduced the output power. Currently a 10 dB attenuator is connected to the beacon, reducing output to a notional 20 mW. I say notional, since I haven't actually measured it, yet. With so little power going out to my vertical antenna, a homebrew 40m helical whip, built by Walter VK6BCP (SK), and tuned to 10m with an SG-237, it's interesting to discover what's possible. Last night my signal was heard in Denmark. Picked up by Jorgen OZ7IT, 13,612 km away. That report broke another personal best for me, achieving 680,600 kilometres per Watt. I was stoked! I shared a screen-shot of my report with friends. One friend, Allen VK6XL, asked a very inte

Foundations of Amateur Radio One of the oldest means of electronic messaging is Morse code. Developed by Alfred Vail and Samuel Morse and sent for the first time on the 24th of May 1844, Morse code changed the way we communicate. For nearly a century it was required to become a licensed radio amateur until in 2003, the International Telecommunications Union or ITU left it to the discretion of individual countries to decide if a budding amateur needed to demonstrate their ability to send and receive in Morse. With that decision many thought that the end of Morse code was only a matter of time. They were wrong. Turns out that use and progress of Morse code continues at a surprising rate. Searching for scholarly articles on the subject, you'll discover that it's used, for communication by quadriplegics, for information exchange between IoT or Internet of Things devices, as a way to secure information combining DNA and Morse code, as a method for gesture recognition, as a research tool for psychologists inter

Foundations of Amateur Radio Having been able to call myself an amateur for over a decade, it might come as a surprise to you that it wasn't until a couple of weeks ago that I thought about attenuators for the first time. They're a curious tool and once you come across them, you'll never be quite the same. Before I dive in you should know that an amplifier is an active tool that makes things bigger and an attenuator is a passive tool that makes things smaller. To look at, attenuators are diminutive to say the least. The ones I have in my kit look like barrel connectors, a male and female connector and seemingly not much else, but looks can be deceiving and I'll mention that shape isn't universal. The purpose of an attenuator is to reduce the power of an RF signal by a known amount, preferably without distortion or any impedance mismatches. When you go out hunting and gathering, your choice of connector is the first obvious selection, but soon after you'll be asked for a frequency range, an impedance, a pow

Foundations of Amateur Radio It's common knowledge that power, as in output power, makes your signal heard in more places. If you've followed my adventures you'll also know that I'm a firm believer in low power or QRP operation. It all started when I was told that my shiny new amateur license was rubbish because I was only allowed to use 10 Watts. Seemingly the whole community around me shared that opinion and slogans like "life's too short for QRP" are still commonly heard. As a direct result of that sentiment I decided to explore and document just how much I could actually do with my so-called introductory license, the Australian Foundation License. I've now held it for over a decade and I'm still exploring and writing. One of my first acts of rebellion was to lower my radio output power to its minimum setting of 5 Watts and half legal power was sufficient to prove my point. Although I'm still regularly being encouraged to upgrade, my second act of defiance is to keep my Foundation License until I deci

Foundations of Amateur Radio Recently I discussed the concept of a VFO, a Variable Frequency Oscillator. It's an essential building block for our amateur radio community. In describing the idea behind it, while making an error in one of the CB radio frequencies, thanks to Ben VK6NCB for picking that up, I skirted around how a VFO actually works. In reality the VFO is a collective term that describes a whole range of different methods to vary a frequency. Naturally I continued my exploration and discovered a whole range of documentation on the subject. I even started writing about how one common method, a Phase Locked Loop or PLL, works and how a VCO, a Voltage Controlled Oscillator, operates as part of that. I'll come back to those shortly. In doing my reading, since, as is often the case, I use my weekly contribution to the world as a method to learn things. I'll investigate a topic and attempt to describe who came up with it, what it means, how it works and what its place is in the world, the who, where,

Foundations of Amateur Radio One of the many acronyms that define the world of amateur radio is VFO. It stands for Variable Frequency Oscillator. That doesn't explain much if you're not familiar with the purpose of it and just how special this aspect of amateur radio is. Much of the world of radio beyond our hobby, like broadcast television, WiFi and Citizen Band or CB, to name a few, uses radio spectrum in a particular way. On a television you change channels to switch between stations. Similarly, a WiFi network uses specific channels to make your wireless network a reality and the same goes for CB, different channels to make yourself heard. Looking specifically at CB for a moment, if you look at channel 8 for example, depending on which type of equipment you have, your radio might be using 27.055 MHz, or 476.575 MHz, or 476.6 MHz. Each of those frequencies can be described as CB channel 8. The first is on the 27 MHz or 11m band, the second is if you're using a 40 channel radio, which is now depreciated a

Foundations of Amateur Radio With the ever increasing pace of innovation, well, change, I'll leave alone if it's actual innovation instead of marketing, we see new software released at an almost alarming rate. There is an urge to stay abreast of this process, to update, upgrade and try new solutions as soon as they are presented to you by well meaning friends and colleagues, not to mention online marketing, uh, reviews and other enticements that make you click the button to install something to avert the fear of missing out. If you've done this for a number of years, actually, who am I kidding, a number of weeks, you'll discover that this comes at a cost. One that the corporate world has attempted to address by using terms like Standard Operating Environment, backups, administrator privileges and other such annoying things that prevent users from trying something new and breaking things. At home and in the shack most of that is not a problem. No corporate IT division around to stop you, but soon you'll di

Foundations of Amateur Radio Yesterday I finally discovered the missing piece of information that will allow me to create a project that I've, if not outright spoken about, at least hinted at. In an ideal world by now I'd have built a proof concept and would be telling you that I've published a GitHub repository under my callsign for you to explore. If wishing made it so. Unfortunately, currently sitting at a keyboard for anything longer than ten minutes or so makes it nigh on impossible to stand up, so you'll have to make do with hand waving and gesticulation rather than actual code, but for now, that's all I have. Consider this a design specification if you're so inclined. So, big idea. Imagine that you have a device that can listen to radio frequencies. This device is connected to a network and it shares the data to any number of different listeners which might each do something different with the information. If you were to do this in the way we watch YouTube or listen to streaming audio, each listen

Foundations of Amateur Radio When people think about and discuss my chosen hobby, amateur radio, there's often a perception that it's old men sitting behind a radio tapping on a Morse key, making beeping noises surrounded by all manner of imposing equipment, stacked thick and high in a tiny room that soon becomes too stifling to spend much time in. While such scenes might exist, often reinforced by old photos and messy radio shacks, any self respecting amateur will tell you that plenty of time is spent outside the shack dealing with antennas, coax and earthing systems, combined with pouring concrete, building, erecting and climbing towers and a myriad of other physical activity. My experience has shown that my own inertia bending acts often involve things like camping, portable operation in ever changing environments, throwing ropes into trees and recovering those later, erecting verticals, tying down squid-poles and other muscular movements like building temporary rotators lashed to the nearest utility ve

Foundations of Amateur Radio A week ago I unexpectedly had my gallbladder removed. As emergencies go, I was lucky to be in a major metropolitan area with a remarkable hospital, supported by a group of humanity whom I've never much interacted with in my life. The staff at Sir Charles Gairdner Hospital were without exception amazing, from the orderlies to the nurses and everyone behind those, I interacted with about fifty people directly during my stay and every single person had a smile to share and an encouraging word to give. As life experiences go it was as uplifting as I've ever had the opportunity to celebrate. Sure it hurt like hell and there were things I'd rather not have to try again, but on the whole it was, if not pleasant, at least memorable. Recovery is going to take a little while and I understand my voice is expected to return to normal in a few weeks having been intubated for most of a day. Half an hour after being discharged from my five days in hospital I was faced with a choice. Produce no

Foundations of Amateur Radio Forgive my briefness. You'll discover why this space was left intentionally blank next week. It involves a broken capacitor, of sorts. I'm Onno VK6FLAB

Foundations of Amateur Radio Over the past while I've been discussing the Amateur's Code and its place in our community. I've shown that it was published in 1927, despite credits to the contrary and it's possible that it existed since 1923. I've discussed the original code, how it evolved and what changes have been made across the decades since. I'd like to take this opportunity to compare the original from 1927 to a revision that I've constructed using the various versions that have been published since. Originally I was going to use the current 2022 version in the ARRL handbook to discuss this, but it's completely different from the one shown on the ARRL website today, which appears to be more recent, that it made little sense to pick one over the other. Back to 1927, or 1923 if you like, written by Paul M. Segal 9EEA, or W9EEA, Director, Rocky Mountain Division and General Counsel of ARRL. The Amateur's Code I - The Amateur is Gentlemanly. He never knowingly uses the air for his own amusement in such

Foundations of Amateur Radio It's been a while since I looked up the word "patriotic". Depending on which dictionary definition you use it could be: "showing love for your country and being proud of it", or it could mean: "having or expressing devotion to and vigorous support of one's country". Synonyms for the word patriotic include "nationalist" and "nationalistic" and it relates to words such as "chauvinist", "jingoist" and "fervent". Jingoist means having or showing excessive favouritism towards one's own country. That said, the original Amateur's Code published in 1927 says that: The Amateur is Patriotic. His knowledge and his station are always ready for the service of his country and his community. The 2022 ARRL handbook says: The Radio Amateur is PATRIOTIC...station and skill always ready for service to country and community. The ARRL website is slightly different: The Radio Amateur is PATRIOTIC...His/[Her] station and skills are always ready for service to country and community. Based on the

Foundations of Amateur Radio When you are absorbed in a hobby like amateur radio it's easy to lose track of the world around you. I freely admit to spending many hours on this hobby and it wasn't until I spent some effort taking stock that I discovered just how much time I spent. The fifth clause of the Amateur's Code attempts to formalise this behaviour and I confess that it's taken me several years to find a more reasonable balance. Let's review the original 1927 published version of this clause. It reads: The Amateur is Balanced. Radio is his hobby. He never allows it to interfere with any of the duties he owes to his home, his job, his school or his community. It's interesting to note that in one of the oldest documents describing our community it refers to our activity as being a hobby. I'm noting this because there have been plenty of treatises written on the notion that amateur radio is a public service and not a hobby. This clearly states that in the opinion of the General Counsel of the ARRL in

Foundations of Amateur Radio The fourth clause of the original Amateur's Code, published in 1927 has a lot to say about the tone of amateur radio. It says: The Amateur is Friendly. Slow and patient sending when requested, friendly advice and counsel to the beginner, kindly assistance and cooperation for the broadcast listener: these are marks of the amateur spirit. The 2022 ARRL handbook tweaks that into: The Radio Amateur is FRIENDLY...slow and patient operating when requested; friendly advice and counsel to the beginner; kindly assistance, cooperation and consideration for the interests of others. These are the hallmarks of the amateur spirit. The ARRL website adds a pronoun and updates some of the language: The Radio Amateur is FRIENDLY...He/[She] operates slowly and patiently when requested; offers friendly advice and counsel to beginners; kind assistance, cooperation and consideration for the interests of others. These are the marks of the amateur spirit. I'm not quite sure what the idea behind th