Foundations of Amateur Radio

Foundations of Amateur Radio What's in a word? When you join a new community you learn very quickly that each community has its own language. A word in one community has a different or extra meaning in another. For example, the word "Snowflake" in one community might refer to a phenomenon related to water and freezing, in another community it refers to a person who is sensitive, easily hurt and offended. If you mix the two meanings all manner of misunderstanding ensues. In amateur radio, one of those words is the word gain. This word is used in many different aspects of our hobby, but today I'm going to focus on one specific use of it, in relation to antennas, antenna gain. This mythical property of an antenna is often used as a way to distinguish two different antennas and in advertising terms, bigger is better, more gain, more better. I'll skip over the marketing shenanigans related to artificially making the number larger by comparing apples and pears, or dBi and dBd and move on to how gain comes about. Let's look at something completely different. A light bulb. One of those tiny ones you find in a torch, or on the front of your bike or even one in your car. In essence we have a gadget that emits energy in the form of light and heat when electricity is applied. The specifics aren't important, but let's just say we're going to ignore more voltage and more amps for the moment. If you have a bare light bulb, light and heat radiates in almost all directions. You can't see any light where the fitting is, but everywhere else is a pretty uniform pattern. For the moment, let's ignore the fitting. If you were to get a piece of black cardboard and drill a hole and put the light through it, you've essentially removed half of the light. Below the cardboard there is no light. Above the cardboard is the same amount of light as before. Half the light is being stopped by the cardboard and it's essentially lost - technically it's getting absorbed and the cardboard is getting a little warmer, but let's not confuse the issue for the moment. If you were to make the cardboard reflective, say some foil, white, a mirror, whatever, the light that was hitting the cardboard would be reflected away from the cardboard and you'd experience that as the light getting brighter. Notice though, it's still dark below the cardboard. In essence you've just increased the gain of your light bulb and it didn't cost you any more electricity to make that happen. Antennas work in much the same way. There are a few more wrinkles. A light bulb is working with light and heat frequencies, wavelengths are between 100 micrometers and 100 nanometres, where the antennas we use in amateur radio typically look at 100 meter to 23 centimetre, so the material aspects of our mirror equivalent are different, but have a similar idea. One thing that's fundamentally different between a light bulb and an antenna in our hobby is that a light bulb is generally only transmitting, where we tend to both transmit and receive with an antenna. Remember when I skipped over the bit of the light bulb below the cardboard being dark? That's the antenna equivalent to not hearing something, which means that you're better able to hear the signal in the direction you're pointing. The same is true for the bit about the light bulb fitting and no light below it. In antenna terms, this phenomenon relates to the front-to-back ratio. Imagine turning your antenna 180 degrees. Pointing one way the signal is of this strength, pointing the other way it's that strength. Divide the two. If they're the same, the front-to-back ratio is 1, otherwise they express the directivity of the antenna. Another number you can use to market your antenna to an unsuspecting amateur. So far we've only looked at using a single reflector for our light bulb, but if you were to use a torch, you'd get even more directivity and more gain. The same amount of energy, pointing at a smaller area. The ultimate expression of this is a laser beam, which is essentially a single focussed beam of light with no light anywhere other than where it's pointing. Antennas do the same thing, using different methods, but the most common one is to add more bits of metal to focus the radio energy. A light bulb emits energy in all directions and an antenna does too. Even if you were to make an antenna made of elements, all aligned in the same direction, the pattern is still mostly round, that is, it's like a cone of radio, regardless of the shape of the antenna. Yes, there are ways of making antennas that don't make round cones, but that's a conversation for another day, but think about this, what would happen if you were to squash an antenna pattern and then focus it? I'm Onno VK6FLAB

Foundations of Amateur Radio How far can I talk on radio? A question that regularly hits the enquiring minds of people who are not (yet) radio amateurs is one about distance. For both amateurs and those who are not ye) inducted into our community the concept of distance speaks in ways that other parts of our hobby don't. It's a simple concept, between these two points, how far can you talk? The interesting thing to me about this phenomenon is that distance isn't a metric that we as amateurs use for anything other than calculating repeater coverage and then only for frequencies that are line-of-sight. If you're not an amateur then this might be unexpected or even illogical. Let me give you two questions: How far can you talk in amateur radio? - and - How far does light shine? If you're an amateur you'll know that those two questions are pretty similar, if not identical for certain frequencies, but if you're not, then these two questions appear completely unrelated to each other. Let me start with something that you might not realise. If you tune to a local AM radio station, let's say ABC 720 in Perth. It's located in the AM broadcast band and the number of the station, 720, is the frequency at which it's transmitting. 720 kHz, or 720 thousand Hz. If you had a radio capable, you could turn the dial to the right, and after passing 810 Radio National, eventually, if you kept turning to the right, you'd find ABC Classic FM at 97.7fm in the FM broadcast band. The station indicator, 97.7 is again the frequency, 97.7 MHz, or 97.7 million Hz. So, 720 and 97.7 are both on the same dial, just at different ends. Now if your radio was capable, you'd be able to keep winding it to the right, and after passing by Wi-Fi, at 2.4 GHz, or 2.4 billion Hz, you'd eventually come across light. Green light for example is about 560 THz, or 560 trillion Hz. You could keep going and end up with even more exotic stuff, like X-rays and Gamma-rays, in the exahertz range, a 1 with 18 zeros, but you get the point. Radio and light are the same thing. If fact, there are experiments around that are using light for Wi-Fi communications. So, How far does light shine is the same thing as How far can you talk in amateur radio? Before you start complaining about when it's different, let me point out that the only difference between these two is the frequencies at which we're comparing, with the characteristics that come with that. I'll get to that in a moment. Look at light. If you have a light bulb that's bright enough, you can see it in full daylight. If it's dark outside then you'll need less of a light bulb to see it. If it's raining, or if there is smoke in the air, you'll need more. If there's a wall between you and the bulb, you'd need a pretty bright light to shine through the wall, but you already know this. Covering up a torch with your palm shows the bones in your hand. Light gets through different parts of your hand in different ways. Another thing you've seen is when you put a straw into a glass and it looks like it's broken. That too is related to how light travels through different materials. You may even have been underwater in a pool and looked up to see a reflection. That too is a phenomenon familiar in amateur radio. Something that you might not realise is that something like an X-ray is identical to shining a light of a torch through your palm. Only X-ray's are used for diagnostic purposes, we shine an X-ray light at your body and some gets through and some doesn't. We take a photo of that and use it to figure out what's under your skin. Back to radio. The same phenomena happen in radio. Buildings are good at stopping certain radio frequencies, in much the same way as they block light, but other frequencies barely get noticed, they shine right through. Similarly, the ionosphere around the earth can act as a reflection like the surface of a swimming pool for some frequencies, but not for other frequencies. Interestingly this changes throughout the day, depending on the sun and a whole range of other factors which I'm not getting into today. Finally, just like with light, you can turn up the brightness for different effects, you'll get further, but only if the conditions allow for it. To answer the original question about how far you can talk on amateur radio becomes much harder and now you know why. I'm Onno VK6FLAB

Foundations of Amateur Radio Recently there was a discussion on social media about the legality of various types of transmissions. Before I get into the specifics, it's worth looking at some of the rules around this. I will point out that this isn't exhaustive, but it gives you an idea of what I'm talking about. In Australia, the rules about this are encapsulated in the Radiocommunications Licence Conditions Determination, referred to as the LCD. It essentially says that you must not operate an amateur station to transmit signals that are encoded for the purpose of obscuring the meaning of the signals, except for amateur satellite and repeater command and control purposes or emergency service operation and training. In the United States, the rules are covered under the FCC rules, Part 97 Amateur Radio Service. It says that you may transmit using a digital code who's technical characteristics have been documented publicly. It goes on to prevent such transmissions for anyone communicating with a country that doesn't have an agreement with the United States. It also states that using unspecified digital codes must not be transmitted for the purpose of obscuring the meaning of any communication and if it's deemed necessary, you must maintain a record, convertible to the original information, of all digital communications transmitted. In the United Kingdom, the amateur terms say that the licensee may use codes and abbreviations for communications as long as they do not obscure or confuse the meaning of the message and messages shall not be encrypted for the purpose of rendering the message unintelligible to other radio spectrum users, except for during emergencies or if used by various emergency or government departments. Just by looking at three different sets of rules we can already tell that law makers across the globe have different ideas of what's allowed and what isn't. I will point out that the rules in the United States are much more prescriptive than those in Australia or the United Kingdom. I'll leave it to lawyers to determine which of the rules is more effective and what their actual effect is on our global amateur community. Let's get back to the original question. What's allowed? The purpose of obscuring the meaning of the message is essentially not allowed. What happens if that's a beneficial side-effect? Is that allowed? For example, let's imagine that I have a new mode that is more efficient than any other mode in getting information between point A and point B. It does this by transmitting a single number, which is simply sent and received, it could even be done with Morse code. Station A knows what the message means and Station B also knows what it means. How they come to a common understanding of the message is something I'll leave to your imagination, but is this kind of transmission in violation of the idea of obscuring the meaning of the message, if all we're doing is making communications faster? Let's say that we have a public web-site that links those numbers we've exchanged to a more meaningful message. Let's say that Station A uploads an image to this website, and then sends an ID number of that image to Station B, which then goes to the same website and looks up that ID and sees the image. Bingo, transmission complete. Message exchanged. It's all public, there's no intent to obscure the meaning, everyone happy. In case you're wondering, I've just described how Hybrid EasyPal works. What happens if I require a password to access the website to see which file was intended for me? Have I just obscured the meaning of the message? Note that I'm talking about two stations exchanging a unique identifier of some sort, that both stations have agreed on, so they can communicate via a password protected website using amateur radio. That appears to be in violation of the amateur radio rules for all three countries. It gets better. What if I build a gadget that makes squeaky noises and knows how to receive them? Station A plugs their microphone into the gadget and talks into it. The gadget makes squeaky noises and those are transmitted. Station B has the same gadget, which understands squeaky noises and makes it into perfect audio. The purpose is to get information between the two stations, no intent to obscure the message, right? What if I only make two of these gadgets? The purpose isn't to obscure, but the outcome is that the messages are actually obscured. At this point we get lawyers involved who argue both sides. Your honour, I wasn't trying to hide my communications, I was just making them more efficient. Clearly this isn't what our hobby is about. It's about exchanging information, un-obscured information, between stations that want to talk to each other. If the intent is to make apples, but the outcome is that you're making pears, you're making pears. I'm Onno VK6FLAB

Foundations of Amateur Radio What would you do if you found that at random times your garage door opener didn't work, or the Wi-Fi network dropped out, or you couldn't switch off a light with an RF controller? That's the position I found myself in and the times at which this was happening were madly unpredictable. One moment everything would work fine and the next all things radio would just stop. As a radio amateur you're likely nodding your head and thinking, radio interference, there's some direction finding in your future. Sure enough, that's the case, but before that, I needed to know if the interference was random, if it had a particular pattern and how widespread it was, since it seemed to impact multiple different devices using different parts of the radio spectrum. Initially I focussed on getting a recording of it. I turned on my radio, tuned it to a 2m frequency and recorded the noise. Only one problem. There was no noise. All I could see was an extreme signal strength, but it wasn't showing up as noise. I enrolled the help of my RTL dongle and recorded some raw data, essentially capturing a 3 MHz slice of noise centred around 147 MHz. All that revealed was that there was noise. I already knew that. At that point I decided that a bigger hammer was needed. Something you can do if you have a $5 RTL-SDR dongle and some free software, in my case I used a tool called rtl_power and a visualisation tool called gnuplot. rtl_power is a nifty piece of software. It takes measurements and averages out the power level across the measurement range. To make it work, you specify a starting frequency, a stopping frequency, how big a step to use to average, how often you want to measure and for how long. For my little investigation I started with measuring between 0 and 1.7 GHz, at 1 MHz intervals, every 2 minutes for 10 days. That creates a big CSV file that you can process with gnuplot into a picture that tells a thousand lies. Seriously, it showed me that the interference was very wide, 0 to 300 MHz, it occurred every 20 or so hours, lasted up to six hour at a time. There were other things happening as well, similar patterns, but across an even larger frequency range, from 0 to 600 MHz, but in shorter duration and of lesser strength. Based on the times alone, I can immediately, almost certainly, eliminate any source under my control. Based on the timings I can also determine that the noise is likely not created by an automatic process, given that they vary in duration and the way they're clustered around specific times. The variation of the interference allows me to determine that there are at least three separate types of noise, each with specific characteristics and times, sometimes overlapping. It's too early to tell if this pattern will continue. One possible next step is to set up the same measurement tool and powering it from a battery. Once I've got that working, I expect to turn off the house power during an interference session and determine if the noise is coming from my house, or if it's an external source, which seems likely. Once I've determined if it's in house or not, I can start either eliminating gadgets by switching off specific power circuits, or I can start direction finding and locating a nearby source of pain. At that point I can decide what to do next. That said, at the moment it looks like several televisions around me are creating an RF noise storm of epic proportions. I've documented all of how I did this and you can find it and the scripts I created on the web at vk6flab.com. One thing that has happened since I started documenting my efforts is the idea that we could collectively as a community make measurements like this and document the state of our RF space and how it changes over time. I plan to update my code to incorporate this idea, perhaps log in 24 hour blocks and generate a chart over that time, perhaps make it into a video. One challenge ahead of us would be to come up with a universal way to calibrate our various dongles, so we all report the same signal level in the same way. One thought is to use the sun as a global calibration, but I'm not yet sure how that might be implemented. One thing's for sure. If you've ever wondered what use can a $5 RTL dongle possibly be, this is one thing that you just cannot do with a traditional radio. That's not to say there's a place for both in the world, just different tools for different problems. I'm Onno VK6FLAB

Foundations of Amateur Radio For some time I've been explaining how some of the internal workings of a Software Defined Radio operate with a view to getting into the nitty gritty of the why and the how. This exploration is happening within the context of a world where there are countless choices for selecting a radio to match your budget. Increasingly that selection process starts with a simple question: Should I purchase a Software Defined Radio or a traditional radio? This is not a new question, previously it may have been: Should I select a radio with transistors or one with valves? Presumably the same happened when your ancestors faced a choice to buy a new car or update their horse and carriage. Of course I'm being flippant, but the point stands, as things evolve, choices change. Today we don't know what comes after the Software Defined Radio that we currently know, but it's likely to force the same selection on future generations of radio amateurs. So, if you're in the market for a new radio, what things should you consider in your selection? SDR is becoming pervasive, that is, the more you look, the more you'll find. Much like transistors overtook valves, not because they're better, but because there's a smaller component count and related price advantage. SDR come in all forms, from nondescript black boxes to a traditional radio form factor and everything in-between. If you choose a black box model SDR, there are tools around that allow you to use external controllers to provide knobs and buttons. These external controllers might be a fully-fledged radio head, or it might be using an external USB connected knob to change the frequency, or you might integrate your solution with a DJ Console, a big panel with lots of knobs, sliders and dials, repurposed as a user interface for your radio. The software behind most SDR platforms appears to continuously be in a state of rapid development. This means that every update potentially gives you more functionality. Of course the opposite is also true, things break, get taken away, get redeveloped, in ways that may be unexpected or unwanted. In my opinion, there's an awful lot of crap software around, attempting to use a computer screen to emulate a physical environment, forcing you to use a mouse to turn a knob, or slide a slider. It's getting better, but so far I've not seen a single solution that does this all well. That's not to say that there aren't any innovative things happening either. For example, something I've mentionned in the past, is the user interface for the diversity receive function inside PowerSDR. You set the phase angle and the strength by pulling on a line inside a circle. There's plenty of open source software around, and functionally it's pretty good. Fortunately Windows is not your only option, Mac OS and Linux provide many opportunities. Traditional radios have not finished, nor are they likely to go the way of the Dodo anytime soon, but while people are getting excited, you can pick up bargains from those migrating away from traditional radio to SDR. If your selection is based on using a computer or not, there's things to use your computer for with a traditional radio, numerous and growing digital modes and other cool stuff to get your teeth into. I should mention that there are radios about that are both traditional and SDR, so you can have the best (or worst) of both. My recommendation is to set a budget and see what that buys you. Regardless of what you end up with, your requirements will evolve. I'm Onno VK6FLAB

Foundations of Amateur Radio From time to time our hobby changes. While the idea that we're all a bunch of old men playing with spark gap transmitters, or using strange noises to the annoyance of others, the reality of amateur radio is markedly different from that stereotype. The changes we experience come from many different sources. As amateurs we're always trying something new, inventing things and building stuff. That type of change is integral to the hobby and in many ways it's why our community exists in the first place. Other changes are external. A new product arrives into the marketplace and we gleefully take possession of a new gadget. That in turn creates other changes which are incorporated into our day to day life as amateurs. A more structured change happens when the regulator makes a proposal, instigates a new rule, enforces an old rule or does something else that affects us. In the time I've been an amateur, I've seen changes happen that originate from the regulator that both benefit and impede our activities. Things like the introduction of new bands, the trial of high power, but also the removal of frequencies, the restriction on modes and across the globe this happens in every single jurisdiction. For example, in Sweden the regulator proposed and then implemented a reduction in transmitter power, from 1 kW down to 200 Watt. I'm sure it made lots of noise in Sweden, but here in Australia there was hardly a squeak. In France proposals have been drafted to reallocate the 2m band to the Aeronautical Mobile Service, to be discussed as an agenda item at WRT 2023. The 2m band is a band that is widely used, often as the first band for most amateurs, a band that offers local communication, hosts local discussion nets, has many options of affordable equipment, uses small antennas commonly installed on vehicles. In Australia the regulator is looking at removing access to the 3.6 GHz band for specific areas and defining more precise access restrictions, removing emission mode and bandwidth restrictions and removing specific Foundation restrictions, such as the ability to build radios, connect radios to the Internet and use digital modes. The Australian regulator is also of the opinion that any station should be able to use 400 Watts, regardless of the license level, since it's unlikely to increase interference. Interestingly, the local representative bodies are at odds with this, since they appear to believe that we need multiple levels of licence, even though I've never actually heard a coherent argument to support that. There's more, but let's move on. What strikes me is that the benefits are celebrated and the impediments are bemoaned with hardly any thought expressed on how these changes happened and what brought them about. There are representations made by representative bodies, but most of that is at arms-length. We're a tiny community in the scheme of things, we always have been, but we have access to one of the richest resources available and we have a regulator who is required to consider our existence when new rules are made and old rules retired. In discussion with other amateurs I hear time and time again that making a submission is hard, it's a waste of time and takes too long. For me that makes no sense. The notion that our tiny community has no impact is not credible in the face of the evidence, so why is it that the idea of making submissions to the regulator is such a waste of time and so difficult? Why is it that we give up before we even start? What is it in our DNA that leaves these submissions to others and what is it that makes us think we're unworthy or unable or unheard of if we never even try. A submission doesn't have to be a book, it doesn't need to have more than one page. You can write a letter to your regulator that says: Hey, I'm an amateur, I'm affected by your proposal and I think the following. My point is this. If amateur radio is important to you, if it gives you joy, if it teaches you stuff, if it gives you a community, if it justifies buying gadgets, then why don't you express that to the regulator when they announce a request for consultation? What are you waiting for? Share your opinion, make your voice count, you can be part of the change. I'm Onno VK6FLAB

Foundations of Amateur Radio It seems my analogy with milk glasses hit a nerve when I explained some of the inner workings of a simple Analogue to Digital Converter, also known as an A/D Converter or ADC as part of my exploration into Software Defined Radio. Thank you for your comments, suggestions and corrections. I did make an error when I said, grab eight of them and you'll have a byte, I'll get into that. Thank you for pointing it out. With my milk glass analogy, if you missed it, without naming it, I drew a picture explaining how a flash or direct-conversion ADC works. Briefly, I said that if you were to pour milk into a glass and continued to do that until you ran out of glasses or milk, you'd have converted a signal into bits. I also covered how a partially filled glass was neither full nor empty and if you ended up with milk all over the desk you wouldn't know how much there was. In terms of electronics, how does this actually work? In essence you're comparing a reference voltage against your incoming antenna signal. The way that happens is you have a series of resistors between ground and your reference voltage. For simplicity, lets say five identical resistors against a reference of 5 Volts. The result is a series of steps of voltage. At the first resistor the reference voltage is 1 Volt, at the second, it's 2 Volt and so on. If you were to compare your antenna signal at the first resistor, you'd compare it against 1 Volt and your antenna signal might be higher or lower. If it's higher than 1 Volt, we'd record a full glass or one and if it's lower we'd record an empty glass or zero. This is done with a nifty circuit called a comparator that compares two voltages. If the signal is higher than the reference, it returns a one and if it's lower, it returns a zero. If that sounds familiar, an op-amp does a similar thing and if you're wondering, a comparator is an op-amp without a feedback resistor. In a circuit diagram you might see a triangle with two voltages coming in, the one you're measuring and the reference voltage with a single output that's either zero or one. Inside that triangle, which you can purchase as a component for cents, you'll find the whole circuit that makes all this happen. I'll acknowledge there is an opportunity here to go into how an op-amp actually works, how it slightly differs from a comparator and more, but we're talking about an Analogue to Digital Converter, which in turn is part of a discussion about how a Software Defined Radio works, so I'll leave the circuit diagram and building an op-amp from basic components for another time. One thing to note though is that this type of ADC is essentially independent of frequency, it's a direct-conversion ADC and the speed of sampling is determined later on in the process. Back to comparators. We have several of these, each comparing the incoming signal against a stepped reference voltage. In actual fact, if you're doing 8-bit sampling, you'd need 255 of these comparators, if you're sampling at 16-bits, you'd need 65535 of them. As I explained with glasses of milk previously, you'll have interesting results if the voltage you're measuring is between steps. You could increase the number of steps and measure more accurately, but as I said before, you're only kidding yourself if you think that solves the actual problem. In the same way, if the voltage you're measuring is higher than the total reference voltage, you're up the creek without a paddle and you won't know what happened, unless you saw magic smoke appear, in which case you know that lightning probably struck somewhere nearby. You could increase the reference voltage, like making the glasses bigger, but that's actually making it worse, since we now have bigger steps between each measuring point. So, a flash ADC is a series of comparators which compare an incoming signal against a reference voltage and returns a series of bits that digitally represent your signal. The final piece of the puzzle is how we get from the bits coming out of the pile of comparators to the byte going into your computer. Basically we're tallying each bit, that is, we're counting how many there are and returning the number as a value to the computer. The speed of this counting process is what determines how fast we can measure our signal. Did I mention how deep the rabbit hole goes? Amateur Radio for me is the gift that just keeps giving, more to find every time you look. I'm Onno VK6FLAB

Foundations of Amateur Radio One of the unsung hero components of a Software Defined Radio is the A/D or Analogue to Digital converter. Its job is to convert the analogue signal that's coming in via the antenna into a digital signal that is processed by software. I've talked about the difference between analogue and digital before and many explanations talk about converting things into zero and one. There are a few steps before that. Imagine a row of identical glasses, let's say eight. Grab a jug of milk and pour it into the first glass. Keep pouring until it's full. Now do the same to the second glass, rinse and repeat until you either run out of milk, or run out of glasses. You now have either a row of glasses full with milk and some spilled all over your desk, or you have some full glasses and some empty ones. Now if you were to mark a one on your logging paper for every full glass and a zero for every empty glass, you'll end up with a row of zeros and ones. Essentially you've converted an analogue signal into a digital one and in effect, this is how an A/D converter works. Each glass represents effectively what's known in computing as a bit. Grab eight of them and you have a byte. I will point out that this is just one example of an A/D converter, there are many others. You may have noticed I've skipped over some interesting things here. For example, what happens when you spill your milk all over the desk? Or what happens if you don't completely fill a glass? This is the bit where the action is. So, let's look at that. If you've ever over driven a microphone or a speaker, heard of clipping, or distortion, those are all equivalent to spilling milk all over your desk. The take-away is that there is an indeterminate amount of milk and no place to store it, so your row of glasses says all full, but you and I both know that there is some spillage. This is lost information, we don't know if there is a droplet spilled or a whole ocean spilled. So, one consideration in picking an A/D converter is how to deal with high signal levels. You may need to either increase the number of glasses, or bits, or you may need to decrease the signal before measuring it. Another interesting thing is what happens at the boundary between full glasses and empty glasses. If you pour one glass full and run out of milk, you're good to go, but the reality says that you'll start pouring the next glass and you'll run out, having a glass that's only half-full. Or is it? Is it half-empty? How do you know? Is this glass represented as a one or as a zero? You could create a row that's twice as long with glasses that are half the size, and at the boundary you'd have a more accurate idea, but you'd still have the same issue, is the glass that you filled only partly, half-full, or half-empty? There's more to come, but the basic idea of converting an infinitely variable signal coming from your antenna into something used by software is a big part of a Software Defined Radio. I'm Onno VK6FLAB

Foundations of Amateur Radio Today I'm going to go sideways to move forward. In amateur radio we consider circuits, components such as transistors, inductors, capacitors, crystals and how they're connected to each other. The framework in which that exists is embodied by the field of electronics and how these components can be mixed together to shape a radio that you can build or buy. In a software defined radio there are electronics and components to be sure, but the bulk of the work is done in the field of software and today I'm going to look at that. Computers surround us, in our work place, in our home, on the street, in our hospitals, across our society. Each of these devices is running a thing called software, as opposed to hardware - a physical thing, software is intangible, in much the same way as your date of birth is intangible. You cannot hold your birth date in the air and point at it. You could write it down onto a piece of paper and point at the piece of paper that has the date on it, but you'd be pointing at a piece of paper, not your actual birth date. Computers work in much the same way. You cannot point at software, nor can you hold it in your hand. You can print it out onto paper, and point at that, but you'd end up with a deforestation problem that far exceeds the stripping of all the trees in the Amazon rain forest. To make matters more complex, there are at least two types of software, human readable and computer readable. You can translate human readable source code into a computer readable executable with a tool called a compiler, but doing it in the other direction is much harder. Think of the ink on the paper that describes your date of birth. You can put the ink on the paper, but putting it back into the pen is more complex. All this is leading somewhere, I promise. A little while ago I started digging into how Software Defined Radios work and if you've been following along on my journey, there'll be parts that you can follow, parts that you sort of get, and bits that seem like black magic. This will be different for each person. My black magic is not going to be the same as yours and the things I understand without thinking might make your head explode. If that's not enough, the goal posts keep moving. As I said, I started digging, much like peeling an onion, removing layer by layer, I've been exploring and learning and hopefully sharing my excitement along the way. The other day a mate of mine came by with a new toy. A QRP or low power HF radio. The device itself is entirely driven by software, that is, it's a Software Defined Radio. It has some knobs and buttons, a display, a power socket, a plug for a microphone, an antenna, a speaker port and some other bits and pieces, but underneath all that is software. What's special about this radio is that the software is Open Source, that is, you can peek inside and see what the code looks like before it becomes ink on the page, the human readable source code, rather than the computer readable executable. I've touched on Open Source before and perhaps I should spend some time on that soon, but for now, think of it as a set of rules that dictate how you are allowed to use source code. As any self-respecting IT geek, I went to the website where the software is available and downloaded it. What struck me was that it was much simpler than I had expected. Don't get me wrong, this is a complex piece of software, not something I'm expecting to pick up in an hour or even a week, but it's simple - as in digestible. I can point at different bits and understand what they do. This part does Morse Code, that does FM, over here is RTTY and look, over here is FreeDV. If you're wondering, I'm describing the UHSDR, or Universal Ham Software Defined Radio project. Built originally by Chris M0NKA and Clint KA7OEI and sporting an impressive list of contributors, this software offers insight into receiving and transmitting using an SDR across a variety of amateur radio modes, including SSB, AM, FM, Synchronous AM, FreeDV, RTTY, CW as well as CAT or Computer Aided Transceiver, sometimes referred to as rig control or remote control, a way of using an external computer to control a radio. The beauty of this software lies in its simplicity. Unlike many other projects, there is no code dealing with Windows, or with Mac OS, there is no mouse, touch screen, or any other complex user interface. There is a limited set of buttons, a few dials and a screen for output. The end result is that the level of complexity is much lower than you'd find if you were to start digging into something like PowerSDR or some other code-base. The point is that the UHSDR project is a really accessible way to start digging into the software behind a software defined radio and another path into this magical hobby of amateur radio. I'm Onno VK6FLAB

Foundations of Amateur Radio Over the past few weeks I've been describing how some of the fundamental concepts of software defined radio work and how some of these operate and interact with each other. You might think of some of these ideas and technologies as unrelated to the hobby of amateur radio, or not relevant to traditionally built radios. Nothing could be further from the truth. Before I go on, I've been trying to find more elegant terms to distinguish between radios built with mostly software and those built with mostly hardware, and I use the word mostly, because a traditional radio like my Yaesu FT857D has software on board and similarly the software defined radio Flex 6600 has traditional components inside the box. For convenience, until I find a better distinction I'm going to refer to these as hardware radios and software radios. When I refer to a hardware radio, think Yaesu FT857D, when I say software radio, think Flex 6600. Back to the topic at hand. The techniques used in both disciplines, hardware and software, apply to each other. So for example, a band filter might be useful in both and use similar if not identical circuitry, but a noise filter, or an audio filter like a Collins SSB or CW filter might only exist in a hardware radio and the software radio deals with the issue using little programs. Similarly, the local oscillator in both determine the accuracy of frequency representation, but a hardware radio might require a screwdriver to adjust, where a software radio offers the adjustment functionality with a single menu option. With my time spent on software defined radio, I'm finding that my understanding of how spectrum relates to the signal and how filters, offsets and various adjustments all relate to each other. Don't get me wrong. The things I'm learning are perfectly able to be represented within hardware radios and the education that goes with that, what I'm saying is that they arrived for free for me with understanding the software defined radio. Let me give you an example. If you listen to a Morse code beacon signal on the 10m band, lets say the NCDXF beacon on 28.2 MHz. If your radio is set up correctly, you'll hear a tone as each beacon does its thing. If you tune slightly off frequency, the tone changes, up or down, depending on how you've got your radio configured. If you've got a Collins CW filter, you might find the whole thing vanishes if you stray too far off frequency. Now here's the thing. The tone you're hearing is actually dependent entirely on how far off frequency you are, so much so, that if you're entirely on frequency, you won't hear anything at all. But you just heard me say that if your radio is set up correctly, you'll hear Morse if you're on frequency, and that's because, setting up the radio includes an offset, in a hardware radio it might be called the CW pitch, and what it does is essentially take your radio off frequency by the pitch amount. You can test this by setting the pitch to 0 and taking the radio off frequency by say 500 Hz. The point is that how this works and my understanding of it, came entirely from the software radio side. My training didn't include the intricacies of hardware radios, but my curiosity got me there by another path. Another way to consider the Morse code signal is to think of it as a tone of 0 Hz. You can't hear the tone, since it's 0, but if you were to move the dial, the 0 changes into something you can hear. While I'm at it, if you've ever wondered what's the difference is between the two CW modes on your radio, when they don't appear to do much at all? Consider two signals, side by side, say 500 Hz apart. From a listing perspective, the station you care about is at 500 Hz and the one you don't care about is at 1000 Hz. Change to the other CW mode and the one you care about is still at 500 Hz, but the other station has moved from a 1000 Hz to 0 and it vanished. I've spoken to many different amateurs over the years and each one learns their craft differently. I hope that my weekly podcast adds little puzzle pieces to your mind that will over time collide with each other and end up with that elusive Ah-Ha moment that makes you smile with a tinkle in your eye and a better understanding of this amazing hobby. I'm Onno VK6FLAB

Foundations of Amateur Radio As a quick recap of what I've discussed before, a Software Defined Radio is a tool that essentially measures the voltage at the base of an antenna system and sends that to a computer for processing. The faster you measure, or sample, the better the representation of what's coming in via the antenna. The traditional view is that you need to sample at least twice as high as the highest frequency you want to represent. You may also recall that an antenna system doesn't just receive a single frequency, the one your radio is tuned to, but all frequencies. So, if you need to build a software defined radio from scratch, your first question might be: What do I want to listen to?, followed by: Which sample rate do I need? If we were to answer the first question with HF, say up to 50 MHz, the answer would be something like a sample rate of 100 MHz, so you can capture any signal up to 50 MHz. So, twice the highest frequency as the one you care about, that's the short way of waving your hands about and ignoring any little inconvenient side effects. Like, what happens to signals above 50 MHz? First of all, your antenna system will still receive those signals to more or lesser degree, they don't just vanish because your sampling tool isn't interested in anything over 50 MHz. The second thing that happens is that the signals between 50 and 100 MHz will turn up backwards between 0 and 50, so you'll effectively hear 51 MHz at 49, 55 MHz at 45 and so on. As a neat little side-effect, for those reversed signals, an upper side band signal will turn into a lower side band signal and vice-versa, but I'll leave that for another time. In case you're wondering, yes, this can be a desired effect. The signals between 100 and 150 MHz will also turn up where they're not welcome, 105 MHz becomes 5, 110 MHz becomes 10 and so on. A different way to picture that is to think of a tri-fold birthday card. Lay it flat on the table, put a 0 in the top left, 50 at the first fold, 100 at the second fold and 150 in the top right. You're looking at 0 to 150 MHz. Now fold it up. You'll notice that 0 and 100 are in the same place and 50 and 150 are also in the same place. If you need more detail, put some in-between numbers, 25 MHz, 75 MHz and 125 MHz and you should see what's happening. I've seen it described as digital origami and it is. The technical term is called aliasing and it's also referred to as folding. It happens in day-to-day life as well. If you've ever seen a wheel running backwards on television or on a film, that's an example of folding. If that's not enough, this phenomenon repeats itself, 150 to 200 MHz is overlapped in reverse, 200 to 250 MHz overlaps normally and so on. You might come to the conclusion that your magic SDR isn't so magic any more, now you have all this other stuff turning up that you don't want to hear. So what do you do? One approach is to increase the sample rate, but as I've explained, it doesn't make the problem go away. But here's the thing: If you were to sample at say 200 MHz, you'd be perfectly fine with any signal up to 100 MHz. Now here's the kicker. If you filter out anything above 50 MHz, and as long as there's nothing left by the time you get to 100 MHz, you're good to go, no more unwanted information, no more aliasing or folding. Essentially what you've just done is created a thing called a bandwidth limited system. You've essentially removed anything above 100 MHz and now your sampling is working as planned and all of the stuff I've said about sampling at least twice the maximum frequency applies. Yes, there's more, but I'll get to that another time, but to give you a taste, what happens if you want to use the same SDR to listen to the 2m band? I'm Onno VK6FLAB

Foundations of Amateur Radio If you were asked to make an image of the Sydney harbour bridge and only use four dots, the viewer might struggle to determine what was the bridge, the sky, the water and the Sydney Opera House. Regardless of the number of colours available to you, the number of dots would not be enough information for most people. You might have a nice piece of art on your hands, but it might be ineligible for the Archibald prize. Even if you were allowed many colours, and just four dots, figuring out if the blue dot was water, sky, or the background of the Australian flag on top of the bridge might be just as complicated. If you were asked to make the image with one hundred dots, and only use black and white, from the perspective of the viewer you'd have a result that was easier to understand. Use a thousand dots, even easier, even if you only used black and white. Now, if you were to use a hundred dots, with ten colours, your image might be just as easy to understand as if it was a thousand dots in black and white. The point is, there are two things going on here. The number of dots and the information contained in each dot. More dots or more colours, or both, will help your image. Similarly, in Software Defined Radio, more dots, that is, more samples, will help and as I've previously mentioned, you need at least twice the number of samples as the highest frequency that you're measuring. But what of the colours in relation to an SDR? Measuring voltage as a human with a piece of paper is pretty straightforward. Provided you've got a Volt meter, a piece of paper and a scribble stick, you're good to go. If you measure your voltage as 1 Volt, you write 1, if it's -1 Volt, you write -1. Similarly, if it's 100 Volts, you'd write 100, 13.8 Volts and you'd write 13.8. We'll get back to colours in a moment. Provided your paper is big enough, you can record as many values as you need and as accurately as you desire. 13.8 or 13.8853, makes no difference to a piece of paper. Computers represent numbers internally using powers of two, called bits. A single bit can represent two values, 0 and 1. Two bits can represent four values, 8 bits represent 256 values and 16 bits represent 65536 different values. The takeaway is that there are a specific number of values that you can represent inside a computer, depending on how many bits you use. Consider the values I've mentioned, 1, -1, 100 and 13.8. That's four different values. If it's not immediately obvious, what ever solution you come up with, tracking positive and negative, tracking small and large, whole and fractions should all be part of the mix. In case you're wondering, we're essentially describing here how many colours or values we are going to allow, or in terms of a computer, how many bits. Let's consider all the values you might measure and represent inside a computer. How many different voltages do you want to be able to record between 1 Volt and 100 Volt? If you allow for ten values, you can record 10 Volt, 20 Volt and so-on, but you can't record 15 Volt. If you allow for a hundred values, you can record 1 Volt, 2 Volt and up, but you won't be able to record 1.5 Volt. If you account for a thousand values then you can record 1.1 Volt, 1.2 Volt and so-on, but you can't record -10 Volt. Remember, our computer representation can only manage a specific list of values and the size of the list is determined by the number of bits you're using. The rabbit hole goes even deeper. Radio signals vary massively in their strength, which is why we use a decibel scale to represent the signal strength, instead of saying station A is a thousand times stronger than station B, we say it has a signal level that's 30 dBm higher. That's comparing a 1 Watt station to a 1 kilowatt station, and in terms of voltage, that's between 20 Volt and 632 Volt. If you're designing a mechanism to store your measurements inside a computer, you might decide to use dBm to record your measurement. Let's say 30 values from 30 to 60 dBm. Sounds great, where do I sign up? Not so fast. What happens if our station is running less than 1 Watt, or if it's running 100 kilowatt, like when you happen to receive a nearby FM broadcast station? Not only do you need to contend with a whole range, called a Dynamic Range of measurements, you also need to deal with what happens to the overall picture. Let me say that in another way. Your voltage measurements at the base of your antenna are a representation of the RF information that your antenna is receiving, or transmitting for that matter. Representing that inside a computer means that the values you're using, and how fast your gathering them, determine how well the RF signal is represented. One thing to note is that the largest values represented by what ever you choose is only part of the problem. A signal that is stronger than the largest value you can record is not going to be recorded correctly. Similarly, a signal that is so small that it doesn't

Foundations of Amateur Radio If you measure the voltage at the base of an antenna and record the readings, you end up with a collection of numbers that represent the voltage over time. These numbers, or samples, can be used to represent the antenna signal inside a computer. An antenna system voltage is an example of an analogue signal, continuous over time, the recorded readings, the samples are an example of digital, discrete and intermittent. It's possible to reconstruct an analogue signal from digital samples and that's exactly what Software Defined Radio or SDR is all about. The process of sampling essentially converts a continuous signal into an intermittent one. As recording separate samples implies, there is loss of information in this conversion. For example, if you sample once a minute, you'd represent a continuous signal as 60 samples per hour, probably enough to reconstruct where you've driven in your car along the highway, but hardly enough to reconstruct the route through the middle of the city, let alone represent an antenna signal that varies millions of times per second. So, how often do you need to record a sample? Turns out that if you sample at least twice as fast as the highest frequency you're representing, you're good to go. So, for sound, the human ear can hear about 20 kHz, so more than twice that, explains some of why a CD is sampled at 44 kHz. If you want to represent the 20m band, up to 14.350 MHz, you need at least a sample rate that's double that, or 28.7 MHz. As an aside, there are other ways to look at this problem. If you managed to move the 20m band down to 0, then you'd only need at least a sample rate of 700 kHz to do this. Let me say that in a different way. The width of the 20m band is 350 kHz. So sampling it would require at least twice that, or at least 700 kHz. Moving frequencies around is something that we've been doing in traditional radios for a long time. The technique uses one or more frequency mixers. This means that combining some traditional radio tools with an SDR gives you even more options. Truth be told however, this idea of moving the band with one or more mixers is becoming less important as technology improves and there are plenty of reasons not to use this. I'll talk about that at another time. So, the first takeaway is that to sample a continuous signal and be able to represent that signal accurately requires a sample rate that's at least twice as high as the highest frequency in the continuous signal. Without going into the actual proof of this, consider a sine wave that oscillates at 1 Hz. If you sample it at anything less than 2 Hz, you'll end up with some cycles being sampled only once, which isn't enough to represent the sine wave. If you sample it at exactly 2 Hz, you'll have two samples on every cycle, but if you happen to sample when your signal is 0, all you'll ever measure is 0. By sampling at a rate greater than 2 Hz, you overcome that limitation. I'll make brief mention of another phenomenon, that of over sampling. An interesting thing happens if you sample twice, three times or more than the minimum sample rate. In short, the higher sample rate improves the dynamic range, noise performance and filtering, all very useful when you are processing radio signals. Cheaper and cheaper hardware are making this very attractive and it explains some of the reasons why SDR manufacturers are using sample rates that far exceed double the highest frequency being sampled, for example, the Flex-6600 samples at 245.76 Mega Samples Per Second, or Msps, even though the maximum receive frequency is between 30 kHz and 54 MHz. In case you're wondering, yes, I'm leaving out a lot of detail here, one thing at a time. The opposite, under sampling, has its uses as well, but I'll also leave those for another time. The second takeaway is that higher sample rates are used to reduce cost, increase performance and reduce component count. Some of what I've talked about can be explored with the popular RTL-SDR USB dongle which is actually a mass produced commodity digital television receiver, made in the millions and accessed directly thanks to the combined efforts of many different people. If you'd like to start to play, $25 should get you a dongle and most of the software you can start to experiment with is free. Check out rtl-sdr.com to get started. If you'd like to get in touch, please do, [email protected]. I'm Onno VK6FLAB

Foundations of Amateur Radio We think of radio as operating on a specific frequency. We select an antenna resonant on a single band. We configure the radio for that same band and then turn the dial or the VFO, or Variable Frequency Oscillator to a particular frequency within that band. All of our language is geared towards this concept of tuning, of picking out, selecting one special tuned, resonant frequency and listening to it. I've said this before, but that's not actually what's happening. Your radio is receiving all RF frequencies, all of them, all at the same time, all the time. Your antenna is better at hearing some frequencies than others, but that doesn't stop it from hearing everything at once. Your radio is getting all that RF information at the antenna connector. After that, every step along the way is removing unwanted information, first it removes all the bands you're not listening to, then the VFO selects which part of what remains to let through to the decoder and the result finally arrives at the loudspeaker. Ultimately, all your radio lets you play with is what's left over. Say about 3 kHz bandwidth. Using traditional radio, if you want to listen to two repeaters, you either need to switch back and forth quickly, or you need two receivers. Now without going into how precisely, imagine an SDR with a bandwidth of 3 MHz, one thousand times larger than your traditional radio. Before you think I'm being fanciful, a $25 gadget can do this. This means that you could process most if not all of the 2m amateur band and then pick out which bits you'd like to decode. You could decode all the local FM repeaters, an overflying satellite, the International Space Station SSTV, a beacon, Morse, Packet, RTTY and simplex contacts, WSPR, APRS, EME, whatever is happening on 2m, all at the same time. Let me say that again. All of the 2m band, all at the same time. The point is that all this information is there, all the time. We can opt to decode or ignore the information. In a traditional radio, you can only decode one signal at a time, but on an SDR, you can extract as much or as little as your computer can handle. Some SDR language talks about using multiple receivers, but a better description is multiple decoders. This means that software defined radio is fundamentally a different way of looking at radio spectrum. Instead of filtering out everything we don't want to decode, we select which decoder to apply to which part of the spectrum. With an SDR you could represent the 2m band as a 3 MHz slice of spectrum as a series of measurements. There is no loss if you reuse the numbers, so if you process the same data multiple times, you have no loss of signal, no deterioration, no extra noise. All we do is feed the same data into each decoder, pick out the bit we want to decode and have at it. There is a misconception that you need serious computing power to do this. That's not strictly accurate. A $5 Raspberry Pi single board computer is more than powerful enough to do this. You can argue that this is serious computing power, compared to what we used to land on the moon it is, compared to your mobile phone, it isn't. I fully intend to go into the maths behind this, but it's not scary, despite what you might think or have been taught. My week has been about the maths and it's become clear to me that there are lots of explanations around, each trying harder than the next to scare you away. If you feel the need to run screaming for the hills when you hear the words Nyquist, Shannon and Fourier, then get it out of your system and come back when you're ready. I'd like to mention that I've been working on how to explain this over much of the week, I've lost count of the number of drafts I've written, but it keeps coming back to the words that are almost as old as I am: My god, it's full of stars. No doubt you might be convinced that I've lost my marbles and that I'm going well outside the Foundations of Amateur Radio, but I have to confess, this is what radio is today, and I'm thrilled to be here learning more about how this all works. Hopefully you are just as thrilled. I'm Onno VK6FLAB

Foundations of Amateur Radio If you've been around the hobby in the past decade, you may have come across the invention of a Software Defined Radio, or SDR. You might even own one and if you've looked into how it works, read the explanation that essentially describes it as a traditional radio where all the components are implemented in software. To me that's like explaining how a radio works by waiving your hands and saying: here is magic. How it actually works is something all together more interesting and thought provoking. If you think of sound, like my voice, coming from a speaker, you can imagine putting a volt meter on the speaker terminals and measuring every second what the voltage is. As my voice gets louder you might measure a large voltage, as I take a breath, it will be smaller. You could chart the different measurements and show a waveform that would represent the loud and soft parts of what I'm saying. The faster you measure, the more accurate the picture represents my voice. For comparison, a CD player does this measurement 44 thousand times per second. If you were to play back those sound measurements at the same rate into a speaker, you'd end up with my voice, and that's actually more or less, what's happening if you're listening to this podcast. Yes, for the purists, there's more to it, but not relevant at this point. Similarly, if you were to hook up a volt meter to an antenna and take measurements, you'd end up with a chart that represented the signal strength that your antenna is receiving and the faster you measured, the better the representation. What it exactly represents I'll come to in a moment. The waveform that represents my voice is actually a very complex signal. In much the same way as a piece of music is made up of different notes, played in sequence and in concert with each other, my voice is also made up of separate frequencies, played together to form the words that you hear. If you were to measure those separate frequencies and draw a waveform for each, you'd see how every one contributes a little to the overall effect, and if you were to add them all together, you'd have my voice again. In the same way, the waveform that represents an antenna signal is made up of all the separate frequencies that go into the overall signal. You might be surprised to learn that an antenna is actually hearing all frequencies at the same time. Some better than others, but typically, all of the RF spectrum at any given time. Your radio is also essentially hearing all frequencies. When you tune to a local station on 720 kHz, you're actually telling your radio to ignore all the stuff that isn't 720 kHz and to only process that small bit of what it's hearing. The selectivity of a radio is the measurement that represents how good your radio is at being deaf to all the things you don't want to hear. To help that filtering, a traditional radio and antenna works by pre-selecting part of the RF spectrum, when you press the AM button on your car-radio, you're selecting which chunk to listen to, press the FM button on the same car-radio, you'll select another chunk. On an amateur radio, you select by choosing the 80m band, the 40m band, etc. Similarly, your antenna is pre-disposed to hearing a particular chunk better than others, but that doesn't make it immune to signals across the entire range. You may have heard described that a Software Defined Radio hears all frequencies at the same time. Essentially it's a volt meter connected to your antenna, spitting out measurements as fast as it can for processing by a computer. The waveform that comes from those antenna voltage measurements represents all of the RF spectrum and it's just the beginning of what you can do next. In the same way that my voice is made up of lots of different parts, all played together, the RF spectrum is made up of the local broadcast stations, the local TV stations, mobile phones, garage remotes, Roy on the 7130 DX net, this podcast on your local repeater, all at the same time, all played together, to make the waveform that represents the measurements you make at the base of an antenna. I'm going to ignore for a moment how exactly we extract the various bits, or how we decode an FM or SSB signal using software, it involves some math, instead we can look at something that is easier to explain. Unlike with a traditional radio, which has to work hard to filter out undesirable information, a software defined radio can filter out information by just deleting those measurements you're not interested in. Yes, there is more to it, much more, but that's the beginnings of how an SDR works. If you'd like to get in touch, please do, [email protected]. I'm Onno VK6FLAB

Foundations of Amateur Radio Previously I've spoken about the dynamic nature of your station. Even if from day to day use, nothing changes, things around you are always in flux. Propagation changes, power fluctuates and the environment in which your antenna operates is dynamic. Mobile stations even more so. A few days ago we had a gale come through, strong enough to do some major damage, rip off some roofs, break some trees, cause flooding, cause power outages, plummeting temperatures, the first of the Winter Storms. Obviously, checking out your antenna after such an event is expected. Better still, stowing your gear before the event is even better. Such extreme weather events are an obvious trigger to attending to antenna health and well being, not to mention, maintenance and repair. The thing is, it's not the only time you should check out your antenna. Every day it's subject to change. The sun rises in the East, follows its path along the sky and eventually sets in the West. The temperature and humidity change throughout the day and continue to change through the night and the next day it starts all over again. Peppered with sun, rain, snow, salt, corrosion, expansion and contraction, your faithful antenna sits there ready for you to get on air and make noise, until one day it isn't. You could just wait until it falls down, dies, perhaps becomes a hazard to anyone within gravity range, not to mention, destroy your radio when you key it up. Or you could check your antenna regularly and look after it. Inspect and test it regularly, run you analyser across it every couple of months, you know the drill. Most antennas are out of sight for most of their life, but they should never be out of mind. During the weekly F-troop net we started discussing this - as well as an in depth conversation about launching wire into trees - and there were several suggestions worth investigating. One amateur pointed out that the level of complexity in the air dictates the amount of maintenance. A log periodic antenna on a rotator needs more Tender Loving Care than a wire hanging off a tree. Another suggested that you should regularly check the tower supports - technically the mast supports - a tower is self-standing and a mast is not - the best way to remember is that is the Eiffel Tower doesn't have any guy wires. Before a storm, if you have warning, you should check the supports, wind down anything that goes up and down and you should think about how you're going to earth the coax. I've previously covered the weirdness that lightning and charge represents, even at distance, so don't wait until it's overhead. There were suggestions of using spark plugs and Mason Jars, but I've got no supporting evidence either way. My geek background is sceptical, but I'm open to learning more. I've seen installations where a coax switch is used where the antenna is switched to a shorted socket, so the inner and outer braid of the coax are connected to each other. One amateur suggested that an antenna tuner is cheaper than a radio, and that if you leave it in place during a storm, blowing that up is cheaper than blowing up a radio, but your mileage may vary. Also, if you have spare cash to burn, I'm happy to take your donation and relieve you of that fire hazard. It's interesting in and of itself that antenna maintenance is often discussed in terms of extremes, lighting, storm, wind, ice, etc. and less so in terms of regular maintenance. Finally, if you're only using a temporary antenna, you're not exempt from this. You're actually likely to have more failure, since the act of erecting and lowering of the antenna is likely to cause more wear and tear. The antenna is the final part of the transmission chain and it should be treated with the same respect as the power supply at the other end. I'm Onno VK6FLAB

Foundations of Amateur Radio Our day to day life is full of communication. We listen, although less and less, to the radio for news and entertainment, sometimes mixed together as food and games for the masses. We can communicate with family, friends and the rest of the global population using a telephone. With the internet as a transmission medium, we exchange text, sound and vision with impunity to anyone who stumbles across it on a mind boggling collection of outlets, websites, social media, email, streaming services to name a few. The vast majority of this kind of communication is a commodity, that means that with little or no training most of the population has access to this. Another aspect of this commodification is that it's reliable. It works most of the time, it's generally good quality, with little or no loss, as in, you speak into your phone and there's an extremely high chance for the other party to hear your voice. While there are occasions that calls drop out, or the audio is chopped up, it's more an exception rather than a regular occurrence. In stark contrast, amateur radio is none of those things. It's not a commodity, it's not reliable, it's a poor man's version of the ubiquitous mobile phone. As amateurs we know why it's not the same, for starters, to make contact between say Perth and Bermuda using amateur radio requires exactly two pieces of equipment. Your radio and theirs. Making this contact with a mobile requires that both ends have a phone. They'll also need a way to connect to the phone network, either a local base station or a telephone exchange, those in turn connect via many different ways to each other, including repeaters, relays, perhaps a satellite, a fibre optic cable or three, too many devices to count today. Extreme level of complexity. I'm mentioning this because it's simple to conclude that amateur radio is obsolete, but its just not true. With the lack of reliability associated with an amateur radio connection comes something that is unique to society today. Thanks to reliable communication, we have come to expect that all communication is reliable, even our experimental hobby, but if you spend any time on air at all you'll quickly realise that for amateur radio, we need to conduct ourselves with protocol, using specific procedures, phonetics, structured phrases, callsigns and the like to overcome some of the aspects of unreliability. Talking on the local repeater looks and smells like a mobile phone chat room, but it's not. It relies entirely on the participants collaborating to ensure reliable communication. Similarly, calling CQ on HF, requires that you understand that the other station isn't on the end of a telephone connection and that parts of what you're saying are going to be missing at the other end. Using phonetics, speaking slower, waiting longer and monitoring, all assist with making contact. If you're unsure about this, just listen in on a local net for regular confusion, or use an online receiver like WebSDR to hear what you sound like at the other end. To make things a little more interesting, every amateur band has a different failure mode. On 20m from one breath to the next, the path might close, on 80m you might get overwhelmed by noise, on 40m you might find yourself all of a sudden sharing the frequency with another station, both of you blissfully unaware of the other's existence. Communication in amateur radio is collaborative and there are common courtesy behaviours. If you're working a rare DX station, that's not a personal friend, don't start a whole conversation about your dogs, your medical issues, or the level of amazingness of your station. You're not alone in attempting to make the contact and they're not there for your personal enjoyment. Hogging the frequency is a sure fired way to acquire the ire of your fellow amateurs, especially in marginal conditions, where band conditions are rapidly changing. There is nothing like getting your feet wet by actually getting on air and making noise, but when you do, remind yourself that this is not a telephone and it's not perfect. Be mindful of your on-air conduct and you'll find a globe full of friends. I'm Onno VK6FLAB

Foundations of Amateur Radio When you get your amateur radio license you become part of a select group of humans who are required to notify authorities if you happen to hear an emergency transmission. Not only that, you're required to offer assistance. The regulator in Australia, the ACMA, says this about it: When a distress call is heard, you must immediately cease all transmissions. You must continue to listen on frequency. You must record full details of the distress message, in writing and if possible recorded by tape recorder. You must also wait for a short time to see if the message is heard by a station better placed to help. If the distress message is not acknowledged within a reasonable time, the amateur is obliged to assist. The regulator goes on to say that after acknowledging or attempting to acknowledge receipt of the distress message, you should immediately forward details of the distress situation to the nearest police station for land based distress situations or the Australian Maritime Safety Authority for air or sea based distress situations. In the United States, the ARRL uses the word may, rather than must, but essentially says the same thing. The FCC, the US regulator, says that an amateur station is not restricted by any rules to attract attention in the case of distress, nor is there any restriction on assisting a station in distress. In the UK, the regulator specifies that instead of waiting for a reasonable time you must wait for three minutes for a Coast Station to reply before responding. Interestingly, getting information on how to respond, what you must and must not do is hard to come by. This in itself is a cause for concern, but let's move on. Using the Australian example and requirements, how prepared are you to do this? Could you actually record the information, do you have a pen and paper next to your radio and can at short notice dig up a tape-recorder, or presumably some more modern recording device, capable of recording audio from your station? Do you have the contact details for search and rescue at hand and are you actually prepared for such activities? During the week, an amateur in Australia reported that they heard a distress signal five hours after the event. While they were at work, their station recorded off-air and they listened to the recording after returning home. Using social media, they asked the question, should they report this information to authorities? The answer is Yes, not only should they, in this case, given that they're in Australia, they must. There was no evidence that any other station heard the distress signal, in fact, the evidence was that the other stations continued to transmit on frequency, either completely deaf, or engaged in more pressing activities like hunting for a contact. I will note that propagation is a fickle beast and it's possible, though improbable, that the other stations on frequency didn't hear the distress call, even through it was repeated. For that reason alone, you should never assume that someone else will deal with it and as I said, in Australia, you don't get the option, you are required to. A couple of other things came to light for that amateur this week. Their recording was in a format that was hard to process by normal audio processing software, in this case the recording was made as an I/Q recording, we should look at that some other time, but processing the file was non-trivial and valuable time was lost in uploading a huge file, and for others to download it for confirmation. There was also indecision about reporting the call to authorities and if so, to which ones. I will say that while we don't know the outcome of the distress signal, we do know that it was reported and that at this point is exactly what is required. The chances that you'll hear a real distress signal in your life are tiny, but if it happens, are you ready for it? I know I have some work to do. I'm Onno VK6FLAB

Foundations of Amateur Radio If the thought of keying up a microphone has you break out in a cold sweat, or the notion of making a mistake sends you into fits of anxiety, the idea of performance in public makes your heart pound, this is for you. Amateur radio is a hobby of communication. The lowest barrier to entry is a hand held radio and making voice contacts with the rest of the community. There is an underlying assumption that this is likely to be the most common way that you'll start getting on air and making noise. Of course you don't have to do that. You could learn Morse Code and never have to open your mouth. You could get a license that's permitted to use a Digital Mode like JT65 or RTTY and let your fingers to the talking. Both those options are perfectly valid and if that's what you need to get on air, be my guest. If you do however want to actually get to a point where you can communicate with other amateurs using voice communication, then let's investigate what voice communication actually entails and what fears might be eating away at your confidence. The most obvious fear, shared by many, if not most amateurs, is the fear of making a mistake. So let's look at that. Apart from blowing up your gear, which won't actually be noticed by anyone but you, those near to you and perhaps your bank manager, blowing up your gear is not a high embarrassment experience. Expensive perhaps, but not so much socially crippling, unless you tell someone that you did it. Other mistakes might be a little more public. For example, if you're on HF, theoretically the entire planet can hear you, perhaps even those space aliens orbiting the Sun and in 4.367 years, those orbiting Alpha Centauri. So potentially, many different individuals and communities can hear you. To counter that I'd point out that most of those will not actually have the means to hear you, or if they technically do, they are likely to be on a different frequency, or otherwise engaged, eating, sleeping, procreating, whatever. The chances that someone actually hears you is very, very low and if you're on VHF or UHF, the audience drops even further. The potential audience is only really line-of-sight, unless you happen to activate a Tropospheric duct, but then that might only double the potential audience, the actual audience is still a fraction compared to HF. You might be afraid that you'll transmit on the wrong frequency. If you've purchased modern properly built and configured amateur radio equipment, the chances of transmitting out of band, into non-amateur frequencies is very low. If you pay attention to what the dial says, and you have a copy of your band-plan at hand, the chances of getting it wrong are even lower. Even so, the band police aren't going to knock on your door within the next 30 seconds, so take a breath. The next set of fears revolve around saying the wrong thing. If you haven't talked on the radio much, or even at all, you're bound to worry about blurting out the wrong thing and being the biggest embarrassment to the hobby in this and the last century. Getting your callsign wrong is pretty common. If you're just starting out, or even if you're more experienced, writing down the callsign on a piece of paper and having it in front of you when you key your microphone is good planning. For every contest I participate in using anything other than my own callsign, I bring a piece of paper and a thick marker for just that purpose. I can still get it wrong, sometimes I even notice. Then there is the topic of the conversation itself. What do you talk about? How long do you talk? How much should you share? The answer to those questions can be summed up with a simple phrase - less is more. If you're establishing the actual contact, a bare minimum is required. You need to first establish that you have their callsign and they have yours. Don't do anything until both those have been confirmed. That goes for both day-to-day contacts and contest contacts. After that, establish how well they are hearing you and how well you are hearing them. Exchange a signal report. If you're in a contest, you'll include the contest exchange while you're sending a signal report. If you're not sure about anything, you can stop there. If you're doing a contest, that's all that's needed and unless the other station asks for your dog's name, or the weather, you can safely move on to your next contact. Your takeaway from this should be that doing a contest can be a really safe way to start. There is minimal information to exchange, it follows a strict format and it's generally over before you know it. Working DX, chasing activators in far away lands can be your next stepping stone, or joining a net on the local repeater might be how you next cut your teeth. You can create a list of things you've heard other people mention and use it to describe your environment. Nothing wrong with making some notes. Most amateurs perpetually carry around a little notebook to scribbl

Foundations of Amateur Radio A topic that rarely if ever gets any serious air-time is the humble station log. It's a process where you track what contacts you've made with whom, when and what conditions prevailed at the time. Notice first of all that I mention that it's a process. A station log is made up of several different moving parts and if you're new to this you might think of your station log as a physical thing. You can actually buy things called Station Logs, looks like a book, it has pages, lines, columns, sometimes pre-populated with headings and as you operate, you write stuff into this book. Let's start with the stuff. What stuff? How much stuff? Have you ever heard another station on-air say something along the lines: Hey Wally, it's been a long time, we last spoke in 1984, how are you and how are the kids? If you thought for a moment that the station had all that information stored away in the back of their mind, that's not to say, some do, but most of the time it's thanks to their station log that this kind of information is at their fingertips. Another thing you might realise is that if you're using paper, like the book I mentioned, then doing this kind of lookup is less than trivial, unless you maintain two logs, one in callsign order and another in contact order. Perhaps you start creating a card file with this kind of information. We do have better tools. At the simplest level, you can create a spreadsheet with your station log. It's simple to maintain, easy to expand, backup, infinitely flexible and for many stations it ticks all the right boxes as a way to store contact information. So, looking at a spreadsheet, what columns should you introduce as a starting point? Well date and time is a good start. Logging in UTC is a solid idea, given that you might move location several times in your amateur career and you might not always be in the same time zone, so if you need to know what time it actually was, you'd need to add a time zone column. Instead just log in UTC, and the time will always be correct. After date and time, you'll need a record of the frequency. You can either record it as a band name, or as an actual frequency, your choice. You'll need a column for the mode, was it an SSB contact, CW or an AM contact, RTTY, FM, FT8, what ever you need to track. You can choose to differentiate between Upper Side Band and Lower Side Band, it's entirely up to you. The next column you'll need is a callsign column, one for the other station. If you have several callsigns, you might also want to add a column for your own callsign. The operator name, theirs, presumably you know who you are, a signal report sent column and a signal report received column and if you're game a comments column. That's the bare bones of the idea. You can expand this to include location information, both theirs and yours, perhaps you'd like to record station information, what antenna you were using, where were you, operating on battery, the power levels, etc. The sky is the limit. Log as much or as little as seems helpful. You'll notice at this point I've not yet talked about specific software. That's because at this point you don't actually know what you care about. For some people logging the bare minimum is enough, for others, recording the whole contact or QSO is not enough and of course there is every variation in between. Once you've become comfortable with what to log, you can start looking for specific tools, what's suitable for your Operating System, your usage patterns, etc. I've said previously that if you're looking at logging software, make absolutely sure that it has the ability to export your data. If it cannot export, then my strong recommendation is to discard that software as a choice, because locking away your data in a flexible environment like amateur radio is a recipe for entering data manually into a new tool and you have better things to do with your life like getting on air and making noise. Now I started off with saying that the station log is a process and so far all I've talked about is the act of logging. The next step in the process is the act of QSL-ing, that is, exchanging your contact record with the other station. There are many different ways to do it, which is food for another day, but tracking where in the process you are, sent QSL, received QSL, confirmed QSL, etc. are just some steps that you might want to track. One of the things that a spreadsheet won't do is track progress. Unless you start writing specific reporting modules, which from an educational perspective might be interesting, tracking progress toward a DXCC, which is contacting 100 countries, Worked All States, Worked All Continents, IOTA or Islands On The Air, SOTA or Summits On The Air and many other awards, you'll get to a point where you'll want to have a report. At that time you can import your spreadsheet into an amateur radio logging tool and generate reports from there. Also, Contest Logging and Station Loggi

Foundations of Amateur Radio On Thursday the 3rd of July 2008 at 6 minutes to 7 at night a developer called Dan KK7DS started to scratch an itch and published the results. The next morning before breakfast Dan added more. Since then about a hundred people from around the globe have contributed to that project. Some people made little changes, others made large contributions over many years. In all, on average, the project saw a change every 29 hours over more than a decade of contributions. On the 16th of July, less than two weeks into the project, it got a name, CHIRP. It's been translated from US English to Spanish, French, Hungarian, Italian, Dutch, Polish, Brazilian Portuguese, Russian and the Queens English. From the beginning of talking to a single Icom IC-92 radio, CHIRP today supports 27 different Icom radios, 36 different brands of radio, hundreds of different radios in all, with new ones being added every couple of months or so. The software runs on anything that will run Python, that includes Windows, OS X and Linux and it does it with an extremely modest footprint and it's free, free in cost and free as in Open Source. If you're not familiar with CHIRP and you have a radio, then it's time to get to know this tool. It makes it simple to program your radio, to configure settings and to make backups of your current channel listings. I should mention that this is not just for hand held radios, there are plenty of HF base station radios supported. When you run CHIRP it presents you with a window where you have a spreadsheet view of the channels in your radio. You can download the channels from your radio or upload new ones. Changing a frequency is as simple as clicking on the frequency and typing a new one, with a full-human-sized keyboard, rather than the poor excuse for a dial-pad your radio has. If your radio supports it, you can supply a human readable name, configure offsets, CTCSS and tuning step size, the mode and several other properties. If you're unsure where to get started, CHIRP even comes with a list of frequencies to get you on your way. You can create different configurations for different types of operations. For example, if you're into SOTA, you can make a configuration file that has all the relevant SOTA frequencies, but when you head back home and want to use the local repeater network, you can build a set for that. If you visit a different state, another country, or if you want to copy your channels from one radio to another, you can with CHIRP. If you want to get started, there's a Beginners Guide, a list of frequently asked questions and you'll find information about what cables to use, specific errors and issues you might encounter and if you're a software developer, you'll find information on how to contribute. If you want the ability to program your radio on any computer, you can download a boot-able CD that will run CHIRP without installing it and if you need help, there's an active mailing list, going back to 2008, an up to date wiki, issue tracker and of course, you can download the source-code, if that's your fancy. CHIRP makes all that possible because one amateur wanted to scratch an itch. What's itchy in your life? I'm Onno VK6FLAB

Foundations of Amateur Radio I grew up with Lego, plastic blocks that you can put together in infinite variety. My oldest Lego kit hails from 1964, kit 324: House with Garage and it's still in pretty good nick today. It's missing the tree and the car and the garage door is broken and a few blocks have vanished, but putting it together the other day reminded me of the art of building. Today I still play with Lego. In fact after a hiatus of several decades I pulled out my old boxes and started sorting my blocks. That lead to building the House and while I was at it, I managed to reconstruct my first Lego Technic kit, 850: Forklift, bringing with it a flood of memories. Why the Lego? It's been my source of inspiration for many decades. It has allowed me to imagine something and then go on to build it. Over the years I've learned that this is not a universal experience. I recall one friend who was gifted a huge Lego car, but had no idea that you were allowed to modify it and I blew his mind converting his four cylinder engine into a V6. That same eye for the possibility exists in all of us. You need to look at things in a different light. One of my friends likes to shop online, he also loves to roam through the local hardware store and I get regular photos of things that are useful. Last night I got a photo of a square washer. Plate of steel, galvanised, hole in the middle with the caption: I've got plans. I took one look at it and knew that I too had plans for that washer, which is why thoughtfully he bought a couple for me too - I didn't even need to ask, it was obvious to us both. The central hole is just the right size for an SO239, so clearly the washer is just right to act as an antenna base. You could weld it to a trailer, or drill some holes for radials, hang it from a tree, make a dipole from it, the sky is the limit and for only 76 cents, what's not to like. I've been looking, like all my amateur friends do regularly, for a pole. I have a large 12m squidpole. It's very helpful to make into a vertical antenna. Use a bit of wire and you're good to go. It's a little floppy if you want to hold anything more substantial, like a horizontal dipole or an inverted V antenna. So, back to the pole. I'm looking in my local hardware store for poles. Of course I could go with the Pine variety, but I'm not keen on carrying a 3.6m wooden pole on the roof of my car, or for that matter, several of them, so I've been looking for other solutions. Tent-poles, pretty cost-effective, strong if you can guy them and the load is vertical, there's painters poles, which will require some testing to see if you can combine several together and make a longer contraption. The point is, I'm not seeing a painter's pole or a tent-pole when I'm looking, I'm seeing the ability to hold something up. In the same way as when Calvin gets his hands on a large box and converts it into a Transmogrifier, I wander the isles of various shopping outlets looking for the possibilities that something might have, rather than the label written on the outside. Doing this is second nature, and achieving it is a matter of practice. The best advice I can give is to walk around with 'What-if' emblazoned on your brain. What-if I could use this as an antenna, what-if I could use this as a battery-box, what-if this fits into my car, what-if this table is big enough for a field-day, what-if. That same what-if attitude will stand you in good stead when you experiment with antennas. Don't be afraid of failing, the more you fail, the better you learn. What-if isn't scary, it's in-built into this hobby of amateur radio. I'm Onno VK6FLAB

Foundations of Amateur Radio The transceiver you use to get on air and make noise needs power to operate. The traditional voltage for our amateur equipment is 13.8 Volts. Why not 12 Volts you ask. The short answer is chemistry, but let's move on, there is lots to cover. Generally that 13.8 Volt is specified with a +/- symbol and some percentage. For my radio it's 15%, which means that if I plug it into power that's somewhere between 11.7 Volt and 15.9 Volt, I'm good to go. Then when you look a little closer at the specification you'll see that my radio draws 22 Amp. That's a whole chunk of juice that needs to come from a power supply. Of course that means that you'll also need to deal with 22 Amp fuses, wire capable of dealing with 13.8 Volt at 22 Amp, and connectors that won't melt when you do that. If you look closer again, you might notice that 22 Amp is when you're using the radio at maximum power, that is, 100% duty cycle and 100% power, and only during transmit, in the case of my radio, 100 Watts for HF. So, if I'm using a digital mode, AM or FM, at 100 Watts on HF, my radio says it will draw 22 Amp at 13.8 Volts. Those numbers aren't correct of you're using CW or SSB. A rough number to work with for CW is 40%, that means if you're doing CW for a minute, that's the equivalent of key down at a 100% for 40 seconds and key up at 0% for 60 seconds. SSB is roughly 4 times as efficient as AM, about 25% duty cycle, but realistically it's more like 20%, since your power consumption depends on how much you're yelling into the microphone. If you take long breaths, 0% power, whistle into the microphone, 100% of SSB, or 25% of overall power. Now all this gets even more interesting if you consider that you're not just transmitting all the time. If you're only transmitting half the time, you need to take your power consumption down another 50%, so SSB might be 10%, CW only 20% and the digital modes 50%, from the perspective of the power supply. So you want to go portable and need batteries. Batteries don't come in 13.8 Volt versions. So 12 Volts. Get the number of amp hour and you're good to go right? Nope. Your battery doesn't just run at 12 Volts and then all of a sudden stop, it runs down, you've seen it in a torch or a Walkman when the tape got slower and slower. A 26 Ah battery should give you 26 Amp for an hour at 12 Volts, but if you actually do that, you'll need to buy a new battery, because you'll have destroyed the one you just exhausted. All of this then starts a conversation about chargers, which incidentally might put out 14.4 Volts. You might turn to solar panels, which at peak power operate at something like 18 Volts, then you stumble into the world of PWM vs MPPT solar converters or charges. Then there's the joys of over and under current, battery discharge rates, continuous versus intermittent charging, different battery types, battery safety, storage, weight, out-gassing and more fun than you'll want to know about on your morning commute. And I haven't even talked about battery isolation, HF interference from chargers and inverters, the differences between powering your radio straight from a battery or via a DC to DC converter, using 240 Volts, or if you're in the USA 120 Volts in the field, generators, compatibility with others and how much all this might cost and if you need to invest in lotto tickets to pay for this experience. One tool I stumbled across in my travels is the Four State QRP Group website which has the W1PNS / WA0ITP / AB8XA Battery Life Estimator, which in a single web page gives you the ability to say what mode you'll be using, for how long with what battery size and how much radio draw and it'll tell you how much more battery you'll need to get the job done. Very handy for a contest that you're hoping to operate portable from a battery. This all to say that power is a very deep rabbit hole and it will take you some time to figure out where your use pattern puts your requirements and budget. Here be dragons. I'm Onno VK6FLAB

Foundations of Amateur Radio Previously I've spoken about the joy of making something out of not much. On that theme I've covered WSPR, the Weak Signal Propagation Reporter, a mechanism to use a modest station to report signals received, which is something any suitably interested person can participate in, no license required. For a time I had my radio, a Yaesu FT-857D connected to a Windows XP notebook running WSJT-X, a piece of software that has the ability to set the frequency of your radio and then listen to what the radio is hearing, attempt to decode it and then report on what was heard. The beauty of this system is that you're using your own station to report signals heard, that is, your own antenna, your own coax, your own radio. Essentially you can use it to see what can be heard from around the world at your station. I had this running for a while, but the set-up was less than satisfactory, because I use the same radio and antenna to run weekly nets, the computer was running Windows XP and running out of disk space since WSJT-X has the option to save all the audio heard, which was clogging up my drive. It also meant that I was required to remember that I needed to reset the volume of the radio, set the squelch just so, disconnect and more importantly reconnect the antenna when there were storms about and a few other annoyances that became just a little too much for it to be fun. After doing this for a couple of months I just gave up and put it into the too-hard basket. The other day I started afresh. I started with a Raspberry Pi. It's a single board computer, about the size of a credit card, that comes in at about $30, is powered off a USB adaptor and runs Linux. Since I've been using Linux for around 20 years now, it seemed like a natural fit. I managed to obtain an RTL-SDR dongle which if you're not familiar, is essentially a USB device that you can use to listen to RF frequencies. Without going too deep, these gadgets started life as USB DVB-T and FM receivers, you know the USB dongles that you can plug into your computer to watch free-to-air TV or listen to FM radio. Back in March of 2010 Eric Fry got curious about figuring out if he could make a Linux version for one of the dongles work by reverse engineering the communication between the dongle and the supplied Windows software. In 2012 Antti Palosaari built on that and published his findings on the linux-media mailing list. Things exploded from there. So, an RTL-SDR dongle, connected to a Raspberry Pi, running Linux. At this point it would be great if I could report success and show and tell everything I've learnt, but then for that to happen I would need to actually have had success and I'm not quite there yet. I managed to decode one, count 'em, one, WSPR packet on 6m, once. Of course I couldn't help myself and started to improve things and since then I've not heard anything. I can tell you that there is plenty of documentation online about the subject, and I'll be adding my version of that once I've got mine up and running. There's a few things to work on, for example, listening on 6m is all fine and well, as long as there are 6m stations within hearing that are on and transmitting. Turns out that the station that I heard once last weekend has been switched off for a week. I've just changed bands, to see if that improves things, but only time will tell. I have also been using a mechanism to change bands automatically every 15 minutes, but without any spots I'm not sure if my set-up is working or not and I've just been unlucky not to hear anything. The challenges continue, but then I suppose that's why I'm here in the first place. I will add that a problem shared is a problem halved. I mentioned my challenge to a local amateur who sprang into action and set-up a WSPR beacon, just so I can test against it. I'll let you know how I go, or you can monitor for my spots on the WSPR website and celebrate when you see a spot with my callsign on it, because I will be, celebrating that is. As an aside, it continues to surprise me that this hobby has its fingers in so many different pies and my chosen profession of IT Geek is just another aspect of amateur radio. I'm Onno VK6FLAB

Foundations of Amateur Radio The hobby we call amateur radio is enormous. One amateur called it a thousand hobbies in one and that just about sums it up for me. Being bored inside this hobby is not an option, because there is just so much to do and see. Yesterday I found a completely unrelated aspect to our hobby, call it the one thousand and first hobby associated with amateur radio. A friend came over and handed me the separation kit mount for my Yaesu FT-857D, it's the bit of plastic that you clip to the back of the head of the radio, so you can mount it somewhere separate from the main body of the radio. I have one of those already, purchased from a local supplier, at the time, 8 years ago, it cost me $80, these days it's included with the radio. For my station I needed a second mount and I really didn't want to spend that much money on three cables and some plastic, so I went hunting for alternatives. One of my friends is doing some 3D printing R&D for his job and has access to a printer to do some rapid prototyping and I wondered if that might be an option. Turns out that I'm late to the party, people have been designing and printing bits for their radios for years. A quick hunt through the popular 3D printing libraries showed about 500 different designs for Yaesu, Elecraft, Baofeng, ICOM and Kenwood, though I should point out that Kenwood also makes food processors and other bits that seem popular in the 3D printing world, so 500 is likely a little high, but respectable nonetheless. I looked at 8 different libraries and found that Thingiverse is by far the most popular for bits with radio brands we know and love. It occurred to me that right here is thr perfect example of how amateur radio is a hobby that just grows and grows. If you're looking for radio mounts, stands, buttons, microphone clips, belt clips, mount adaptors, holders, cradles, plug covers, brackets, earpiece retainers, logos, callsign stands, cogs, gears, handles, caps, pins, latches, cases, tuning knobs, CW key brackets, stacking brackets, antenna adaptors, feet, desk stands, shoulder strap holders, battery compartments, you're good to go. I should mention that you don't even need to invest in a 3D printer at this point, you can hand the design to a printing service and get your print shipped to you in the mail. If you cannot find what you're looking for, you can fire up a 3D CAD program and get designing to make something precisely to your own specifications and based on the current tools available, you can even see what it's going to look like by the time it's rendered in the plastic and colour of your choice. I've only mentioned radio bits, but there's nothing stopping you from printing ladder line separators, dipole centres, antenna brackets, tuner cases, project cases for your home-brew contraption, knobs and dials, buttons and connectors and other missing parts or hard to find pieces. If you're using standard components like a Raspberry Pi or Arduino, you'll find cases ready to go for those as well, so the more you look, the more you'll find. The point of all this is that amateur radio is a hobby that goes far beyond someone sitting behind a radio listening to beeps, pops and crackles. Manufacturing and amateur radio go hand-in-hand and have done since the very beginning, but there's no rule that says that you have to keep using traditional tools to build what you're imagining. The sky is the limit, and based on the efforts of CAMRAS, the CA Muller Radio Astronomy Station, PI9CAM based at the Dwingeloo Radio Telescope in the Netherlands, who captured a photo of the far side of the moon using a camera linked to an amateur radio transceiver on board of the Chinese Longjiang-2 satellite, even that limit is being explored. I'm Onno VK6FLAB

Foundations of Amateur Radio We tend to spend most of our energy looking at antennas and power to evaluate how well our station works. Based on a better antenna or more power, you're likely to make more contacts is the general gist of the process. Being a QRP operator, power rarely comes into the conversation, 5 Watts is what you get, leaving antennas as the prime method of discovering how effective we can be. Recently I received an email from Layne AE1N, pointing me at an article he wrote on the Nashua Area Radio Society website titled: It's all about the decibels - factors in enhancing station effectiveness. The article, goes into great detail in looking at an alternative way of measuring how well you're doing and builds on the December 2013 QST article - How Much Punch Can You Get from Different Modes? In our hobby we measure using a thing called the decibel. I've spoken about it at great length previously. The way to use it is to compare something against something else. Using the metric used in the QST article we take as a starting point a modern transceiver, using 100 Watts, CW into a half-wave dipole at 30m. Everything we're discussing from here on in, is related to that starting point, the zero point. I should also make clear that we're talking about the ability of the receiver to decode your message, not the strength of the signal. If you were to use the same radio and instead of using CW, used AM, you'd have a station that was 27 dB worse off. That is, your signal would effectively become harder to hear by 27 decibel. On the other hand, you if were to replace the half-wave dipole with a 4 element Yagi, your station would be just under 7 dB better off, that is, it would be easier to hear you by 7 dB. Of course you can combine AM and the Yagi, adding the two measurements together, coming out at minus 20 dB, which means that compared to a 100 Watt transmission on CW into a half-wave dipole, the same 100 Watt transmission on AM into a 4 element Yagi would still be harder to hear by 20 dB. If you go from CW to SSB, you'd be 17 dB worse off, or SSB is 10 dB better than AM. Note that when I say better and worse, it's about how much your signal can be decoded at the other end, using the same receiver, antenna, etc. The whole article includes comparisons between CW and FM, CW and RTTY and so-on. RTTY is only 4 dB worse than CW, but most transceiver manufacturers recommend that you reduce power to a quarter power, that is, 25 Watt instead of 100 Watt when using RTTY or Digital modes, so you end up losing 14 dB for that, making RTTY slightly worse than SSB if you follow the manufacturer instructions to reduce power. This isn't all doom and gloom however. Even though CW is very effective, we can improve things in other ways. For example, using PSK31 gives you a 7 dB head start, switching from CW to JT65 or FT8 gives you 25 dB. Even if you take into account the reduction from the loss of full power, 14 dB, you still end up in front by 11 decibel, which is more than you can get from upping power from 100 Watt to 400 Watt which only gets you 6 dB. Adding an 11 element Yagi gives you a similar improvement as changing from CW to FT8, just over 11 dB, and using 1500 Watts is only slightly better at 12 dB. The point I'm making is that you can use this idea to figure out how to get your signal heard. More power or a bigger antenna is only part of the conversation, picking the correct mode is just as important. Of course, the 11 dB gain you get from moving from CW to FT8, even when reducing power, is one of the main reasons that it's so popular, much easier to change mode than to build a new fancy antenna. One more thing, what of the 5 Watts vs. 100 Watts we started with, 13 dB. That's significant, but if you were to use 5 Watts FT8 into a quarter-wave dipole, using 100% of the 5 Watts, you'll actually be 12 dB better off than the same station using 100 Watts CW. Check out Layne's article for a reference to QST and a whole lot more. It's a very useful way of looking at how your station can be very effective, even if you're QRP. I'm Onno VK6FLAB

Foundations of Amateur Radio Operating your amateur radio station at home, in your shack, is one of the often discussed aspects of our hobby. Much has been said about installation, antennas, grounding and the like, but what if you want to operate mobile? Picking a location, of all the locations available to you, can be quite the task. For some it's daunting, others find it challenging, others take to it with ease and often you find yourself overwhelmed by choice. What makes a good operating location, what should you look for and how do you do this better? First thing to consider is that options give you choice, choice gives you uncertainty, which can lead to stress and other unpleasantness. If you're completely flummoxed as to how to select a location, visit the Summits On The Air website, or the World Wide Flora and Fauna site and see which of the qualifying locations is reachable for you. The choice becomes much easier if you don't have a choice. Picking from a proscribed list makes it easier to start and the more you do it, the more you'll learn about what makes a good operating location and what doesn't. Restricting your options is one path to success, but there are others. Over the years I've poured over maps, looked at places that qualified, tried and failed, many times. Things I look for when I am hunting for a new place to operate from include the ability for my car to get there. I live in Australia, often shade is a consideration, away from buildings and other sources of interference. I tend to go for places that have water nearby, preferably the ocean, but I also frequent lakes and rivers. If I'm operating on VHF and UHF for a local contest I might look for a high point, something that has clear line of sight to the local amateur community, in my case a high hill or the local ranges overlooking the city basin. For one contest I needed to visit local shires and to do that I created a map showing all the shire boundaries. I then used that map to scout possible locations and took into account how to get from this shire to the next. I learnt from that exercise that the ground beneath the operating location matters, sand versus gravel, gravel versus granite, granite versus swamp. I also learnt that overhead power lines are hard to spot on a map, but avoiding them is essential to success. Depending on how long you plan to operate for, an hour, a day, the weekend, select a location based on the time that you're there. Picking an isolated jetty where there is potential for crime in the middle of the night is probably best for day-time activations, but might need reconsideration for an overnight adventure. Picking a local park might be possible for 24 hours, but the local ranger might not appreciate you setting up a more permanent camp. Often planning works to your advantage. The local council might appreciate you having a chat with them before a contest and might even offer you assistance in the form of local facilities, running water, etc. Consider using the local public open space with a community hall as your base. There's a balance to be found between preparation and turning up on the day. If the location is something that you're only visiting for an hour, you won't need to scout, unless you're planning on a particularly elusive DX contact, but setting up camp for 48 hours with tents, masts, coax and operating positions will benefit from a visit before the actual event. Make sure that you bring along a radio that can operate on the bands that you're planning to operate on and remember to turn it on and have a listen. I can tell you that driving for 90km to scout a location and forgetting to actually turn on the radio is an experience that I cannot recommend. There are many places to choose from. Radio considerations aside, I mentioned shade before. The environment is important. You don't want to set-up on the side of a highway with fast moving traffic, or in a location where people will come right up to your station to get to their cars. You don't want to select a large car park where others will, for inexplicable reasons, park right next to you. Boat ramps and jetties are good, a national park is great, a beach-side car park, the top of a hill, next to a river, are the kinds of places where you'll find an operating position that will get your mobile station up and running. Bring along stuff. Batteries, squid-poles, rope, wire, spare coax, a table, water, a chair, your logbook, a box of tools, the little things that will give you options for when something unexpected happens, like the tree you were planning to use is further away than expected, or the shade moved, or the rubbish bin on site is just a little too close for comfort. Also bring fly spray, a rain coat, some food and consider any other things that might affect your enjoyment. Essentially, build in some flexibility. I'll leave you with this question. What operating positions have you used and how successful were they? I'm Onno VK6FLAB

Foundations of Amateur Radio Today I have a new callsign, it's exciting, special, kind of strange, to be known as something other than VK6FLAB. It's hard to overstate how much of your identity as a radio amateur is linked to your callsign. It's a strange phenomenon to those who are not amateurs, or who have only just joined the community and are still learning to remember what callsign they have. We think of callsigns as semi-permanent fixtures, but realistically they're far from that. In your life as an amateur you'll operate many callsigns, even if you never change your own. When you're operating the local club-station, you'll use that callsign, or when you're participating in a special event, say an activation of an island, or some remote DX station, or when you get on air to make noise in another country. Some stations use special contesting callsigns, either for speed, or to commemorate another amateur. There are those who collect callsigns like badges, others only ever register one and keep it for the rest of their life. There are provisions for applying for callsigns for short duty operation, sometimes as little as 24 hours, to mark a significant event or activation. For example, in 2013 we registered VI6PROF as a special callsign for the then Chief Scientist of Western Australia, Professor Lyn Beazley, who used that callsign for two hours after dinner during the annual conference held in VK6 that year. There are callsigns registered for marking the end of Polio, VI6POLIO, 100 years of the Wireless Institute of Australia VI100WIA. VK100MARCONI commemorated the first direct wireless message from the UK to Australia. There are callsigns registered for activating an island, like VK6WDI to activate Woody Island between the 9th and the 12th of November 2012, or VK6CHI for the Cheyene Island activation in 2007. Special callsigns are a global phenomenon. The Straight Key Century Club operates K3Y. K1A gets used by amateurs throughout the USA for many different events, from Boy Scout camps through to the America Recycles Day, from the Georgia QSO party to the ARRL Field Day. The 2012 Olympic Games in the United Kingdom were celebrated with 2012L and 2012W callsigns. RG22RQ was for the Winter Olympic Games in Sochi. As with anything rare, there's an active community that collects it. For special callsigns, there are amateurs who collect by trying to make contact with an elusive call, confirm their contact and receive a QSL Card to decorate their shack with. In Australia, three times a year, on Australia Day, the 26th of January, on ANZAC Day, the 25th of April and on ITU Day, the 17th of May, a licensed amateur gets a special callsign to commemorate those special days in the calendar. Australia Day is the official national day of Australia, marking the anniversary of the 1788 arrival of the First Fleet of British ships at Port Jackson. ANZAC Day is the national day of remembrance in Australia and New Zealand that broadly commemorates all Australians and New Zealanders who served and died in all wars conflicts and peacekeeping operations. It's marked on the anniversary of the ANZAC landing at Gallipoli in 1915. ITU Day is the World Telecommunication and Information Society Day, commemorating the foundation of the International Telecommunications Union on the 17th of May, 1865. On each of these three dates, radio amateurs in Australia can replace their VK prefix with AX and use their special new callsign on-air to make contact anywhere around the world. So, for now, I'm Onno AX6FLAB

Foundations of Amateur Radio In 2017 a new digital amateur mode called FT8 joined the ranks of inventions related to our hobby. Since then it's taken the amateur world by storm, filled the bands with contacts and attracted a strong following among radio amateurs across the planet. Making contacts with low solar cycle numbers has never been so easy. Together with that following comes a growing chorus of those who decry this addition, the filling of our air with useless noise and it's too easy, not real radio, there's no conversation, who cares about contacts, I want to rag-chew, anyone can do this and it's not right. Clearly some think of FT8 as the end of amateur radio as we know it. Recently I came across a list of other technologies that made amateur radio too easy and would cause the end of our hobby. Amplitude Modulation or AM, Semi-automatic CW Keys or Bugs, Vacuum Tubes, Single Sideband or SSB, Radio Teletype or RTTY, Repeaters, Electronic CW Keyers, Transistors, Electronic digital programmable computers, Antenna Rotators, Integrated Circuits, Digital Signal Processing, Microprocessors, the Internet, CW Decoding Software, Automatic Link Establishment or ALE, Packet Radio, DX Clusters, Pactor and PSK. Of course some of those make current amateurs just shake their head, or laugh out loud. Who could imagine that AM or SSB would cause the end of the hobby, given that they replaced spark-gap transmitters, which incidentally became prohibited in 1934. As we invent new things - the ARRL referred to FT8 as the Latest Bright Shiny Object in Amateur Radio Digital World - we learn more, have more, do more and expect more. In 1675 Isaac Newton said: If I have seen further it is by standing on the shoulders of Giants. Every invention builds on the ones that came before it and apart from the banning of the spark-gap transmitter, each of these newfangled baubles has made it into the mainstream of our community, to the point of being ubiquitous. Can you imagine an amateur radio without AM or SSB today? Using Clublog aggregate data as the source, with almost 30 years of records, in 2002, CW became more popular than Phone for logging contacts. This is on the back of Phone contacts reducing overall as a percentage of logs, against the increase of RTTY, PSK and other modes. In 2017 FT8 joined the fray and both Phone and CW logged contacts reduced markedly. Interestingly RTTY continues to be used though not at the levels seen at its prime between 2005 and 2010 or so. As an overall percentage of contacts, FT8 is by far the most popular. 2018 showed that over 40% of logged contacts were on FT8, CW remains essentially stable at 30% and Phone contacts account for 20% of overall contacts logged on Clublog. What this shows is that amateurs go where the contacts are. When CW worked better than Phone, it became the prominent mode. While CW use stayed the same, and Phone reduced, it was because contacts were being made with PSK and RTTY and other modes. This doesn't reflect the death of a hobby, far from it. It reflects the pragmatic nature of making contacts. You use a mode that's going to work. When amplifiers and big antennas were the name of the game, those were the tools being used by our community, but these days, FT8 has levelled the playing field for all comers. In a world where noise is ubiquitous and large antenna farms are possible for a select few, FT8 is making it possible for people to get on air and make some noise. No doubt some will decry that these are not real contacts and that exchanging a signal report isn't a real contact. Of course it is. It's just a different contact. Just like a CW contact isn't the same as an SSB contact and glorious AM isn't the same as FM, a contact with FT8 is like any other, it's real, between two stations using radio gear. I should point out that the logging information I looked at comes from Clublog and that in 1990 there were 2.4 Million QSO's logged. In 2018 there were 40.4 million. In the same time CQ WW increased the number of entries by almost 200%. Interestingly, CW logs outpaced SSB logs in 2003, 2006, 2008 and 2016. On the 31st of May 1897 Mark Twain said: The report of my death was an exaggeration. I think we can safely say that Amateur Radio isn't going anywhere and FT8 isn't killing the hobby. I'm Onno VK6FLAB

Foundations of Amateur Radio One of the single most recurring topics within our community is that of antennas. Everywhere you look is a story or a photo or a website or a contact about an antenna that came into being because somebody had an idea. Now if you've been in the ideas field for a while you'll have learnt that having the idea is often just the start of the process. After that there's planning, sourcing, building and testing. If you're lucky you'll end up with something and a story to tell. If you manage to persist you might even end up with a working antenna. The other day I managed to have an idea that I'd not seen anywhere else. As it turns out and perhaps not unsurprisingly, I'm not the first to have this idea. Despite that, what struck me is that I'd not seen or heard of this combination of antennas before. As you might recall, one of my earlier forays into antennas consisted of purchasing a set of mono-band antennas. I intended to use these on my car while operating mobile, but despite countless unsuccessful attempts at making them work, the project ended up being abandoned and written up as a learning experience. That said, each of these antennas works just fine on a roof, just not on the roof of my car. Recently I'd been reading about how much separation is needed between antennas that are resonant on different HF bands and my research unearthed the idea that while they might affect each other to some degree the overall effect appears to be not that large. Combing that with an antenna called a fan dipole, I wondered if I could do the same with some vertical antennas. As it turns out, yes you can. It's sometimes referred to as a fan vertical. Before I get too carried away. A fan dipole is an antenna that consists of a set of dipoles that are all fed from the same feed point. Imagine three or four dipoles, each for a different band, with each centre connected to the same balun. Each of the legs are spaced apart so they're not touching. After a bit of tuning you'll end up with a combination antenna that works on each band. The beauty of this is that it takes up the same amount of space as the largest dipole and you'll only need one feed line, rather than several. You'll also only need two sky hooks, so you won't have to plant a forest before setting up your antenna farm. For all those reasons I wondered if I could make a single feed point for all my vertical antennas and get the same benefits. At one point I got so excited that I started modelling this in cocoaNEC, an antenna modelling tool based on NEC2, but my learning curve exceeded my skill set, so I had to postpone that in order to actually do some income generation instead. Discussion with fellow amateurs encouraged my tomfoolery, unearthed prior work and assured me that it would work and since then I've started down the procurement phase and have now got some SO239 connectors, a piece of metal and ideas to space holes evenly with a central socket to connect my coax to. I plan to solder all the connector centres together with some thick copper wire and use the metal plate to connect all the shields together. The only fly in the ointment at this point is my unhealthy relationship with drills. You might remember that I managed to drill a hole in my hand a while back - all healed, I was incredibly lucky, a delightful scar to remind me - so if at all possible I'd like to avoid such a thing. Last time all I wanted was to make a single hole bigger, this time I've got four 16mm holes to drill. You'll be pleased to learn, just as my partner was, that I'm now able to use a drill press and I even splurged and added a vice, so if I'm not too clumsy, I should be able to avoid stitches this time around. What I'm hoping to achieve is a little group of vertical antennas, connected to the same coax, mounted on the metal roof of the house, all but invisible to our neighbours without needing to swap antennas in and out like I currently do and actually use those lovely mono-band antennas I purchased so long ago. I may have to experiment with radials and tuning and no doubt there's still a gap between theory and reality, but I'll let you know how I go. My question to you is, what antenna project are you working on? I'm Onno VK6FLAB

Foundations of Amateur Radio The hobby of amateur radio is a curious animal. It sits at the junction between empirical evidence and the scientific method. On the one hand it's all about physics, electricity, magnetism and the science behind those. On the other hand it's about trying something out and seeing what happens. When I started in this hobby, I was all about the science. I wanted to know "Why is it so?" "What evidence is there to support that?", all the typical questions you might ask if you're coming at this from that direction. As is often the case, the more you know, the less you know. That is, the more you understand a topic, the more you understand that you know nothing. The deeper you dig, the more variables become apparent, the deeper the hole goes, the further away from absolute you travel. That's not to say that our hobby is unknowable or non-deterministic, far from it. It's often so complex as to defy immediate explanation using high-school physics. You'll get to a certain point with that knowledge, then from one moment to the next you'll open a door into a world where that knowledge is just not enough. Interestingly when you look at for example the standard way of determining the length of a dipole, a fixed number divided by the frequency, that number we use, what ever the value, is an example of an empirical evidence based number and as observations go, it's not a particularly good one, which is why when you start using it you'll find all manner of exceptions, alterations, modifiers, etc. If there was a formula for a dipole, it would not just have that fixed number and the frequency. Nor would it be a simple division, since the number of variables is likely to head to infinity by the time you actually approach something that can model the real world. Between those two extremes, the quick-and-dirty empirical calculation and the intricate model at the scientific end lies a point of "good enough". The point of "good enough" is where what you're calculating is likely to end up with something that works most of the time. It's not 100% accurate, nor is it trivial, but it gives you a level of confidence that the thing you're calculating is useful and reproducible in many circumstances. I've been told by those who have told me that they know, that the fixed number divided by the frequency is on that "good enough" point, but my experience and the evidence says otherwise. Oh, that's ok, just add 5% to that number, or just cut it long, or insert some or other correction factor to account for the variation, that will give you "good enough". Ok, I'll bite. If that's "good enough", why are we teaching our new amateurs that this is how you create a dipole, no explanation about the variations, the effects of the environment, the material used, just: "Here's a number that you divide by the frequency and you'll have a dipole." My point is that it's time to revisit some of the things we think are "good enough" and look for something "better". I'm not advocating that we all need to become theoretical physicists, though for some that might be just the ticket, but I am saying that we should not just state that making a dipole, or calculating anything associated with our hobby, should be done without context. Here's some context for the magic number 468. Ward N0AX did the research almost a decade ago. It's a fascinating read, look it up! Turns out that the first occurrence of the magic of 468 comes in the form of 438. Yes, that's correct, 438 was the first attempt at making a magic number and it was based on measurements by G. William Lang in 1926 and it was based on averaging measurements for several antennas. In the 1929 ARRL handbook the number 468 first appeared and has been repeated ever since. Apparently as it turns out, the more you repeat something the more it's right. To the point of being ridiculed if you dare question the validity of such a notion. So, what is it, scientific, or empirical, or is it a little of both? I'm Onno VK6FLAB

Foundations of Amateur Radio Over the past year and a half I've been working on a secret project. Today I'd like to share what I've been up to. To set the scene, I'm not doing this on my own, a fellow co-conspirator is Randall VK6WR who became an amateur about 20 months ago. Randall has a long association with the Engineering Development Array and the Murchison Wide Field Array, two of several radio telescopes that are built on one of the few radio quiet areas in the world and located near the future home of the Square Kilometre Array, the SKA. One day Randall and I started talking, as you do, new amateur, new topics, interesting new fields and ideas. We hit on the idea that radio astronomy telescopes are able to receive 2m signals. This started a discussion about using a radio telescope to receive a moon-bounce signal. So, the idea was born. Can we create a 5 Watt signal, bounce it off the moon and have it be heard by a radio telescope? Randall and I have been working on that on and off since our first discussion. Let me start by pointing out that we've not managed this yet, but we think it's a project worth doing, to forge cross skill exploration by various different groups. I have a strong background in IT and a few years as a radio amateur; Randall brings with him a wealth of radio astronomy engineering expertise, not to mention signal processing, communications and myriad other skills. We started to do this on the quiet, why talk about something that hasn't happened, might never happen, could be done by someone else who'd claim the glory before we did, and so-on. I've come to the realisation that while those things all hold true, this is a non-trivial project to achieve and anyone who puts in the work and gets there is welcome to claim the glory. So, in the 20 months gone by, while both working full time we've done lots of things. Let's set the parameters. When we first started, both of us were holders of an amateur foundation license. This means hand-keyed Morse, 10 Watts and band restrictions. Because I'm me, I decided that the difference between 10 Watt and 5 Watt wasn't significant enough to make or break this, so we went with 5 Watts QRP. Our license precludes the use of WSJT modes, invented by another radio astronomer, Joe K1JT, so the signal had to be something else. We settled on a manual slow Morse signal. We're using a radio telescope at one end, so it had to be on 144 MHz. Those decisions made, our first project was to attempt to calculate if we could actually achieve this. Conventional wisdom says no, but our ongoing calculations revised several times since our original effort, show that we're right at the edge of what is possible. We then started the process of determining if the radio telescope could actually hear moon bounce radio signals. We have a limited field of view, roughly 20 degrees around vertical, so the moon has to essentially be above the telescope. The galactic centre is a very noisy place from a radio perspective, so it has to be at least 20 degrees away from the moon. Similarly the sun, also very noisy, needs to be 20 degrees away from the moon. That started a process of me learning Python, so I could use Astropy to create a table with observation times that match those criteria. I'm still working on that. Having been a programmer for 35 or so years, I'm not a fan. We did some manual calculations to do some test runs and had two amateurs send a signal to the moon, which for several reasons, we were not able to detect. Traditional Earth Moon Earth, EME, communications benefit from ground gain, something like 3 to 5 dB of gain based on the path essentially ducting across the earth, but that requires the moon to be near the horizon, so not relevant for our project, since the moon needs to be overhead. Of course, it might mean that I need to travel half-way across the globe, so I can get the gain, but that's another project for another day. We get some effective gain from having a very stable signal. You might recall I purchased a high stability compensated crystal module, a TCXO, for my radio a while back, this project is why I did that. Another thing I purchased at the time is mechanical filters which also provide a little effective gain. We started the process of acquiring some high gain 144 MHz Yagi antennas, but through some miscommunication with the amateur who was selling them at a really nice price, we missed out and haven't yet bit the bullet on another set. Initially when Randall and I started this, we were working on it on our own, we tried to learn as much as we could and test the waters ourselves. We've been at it now for a while and it's become apparent that this is going to be something that is likely to involve several other amateurs. Some have already been helping, Allen, Allan, Keith, Alek, Leigh and Marcin all contributed time and material. No doubt this list will grow as the project continues. At the moment I'm still trying to write code to create a calenda

Foundations of Amateur Radio Often we forget the things we've done or achieved and every now and then it seems like a solid use of time to reflect a little on what went before and what that did. Recently I asked various amateurs what they were proud of having done or achieved in the past year, their little personal victory, their thrill to keep coming back to the hobby. For me it was the research and production behind "Is man-made noise really vertical?". It took several weeks to research and produce and received only a handful of responses on social media or via email, even though it was downloaded and read about 10,000 times or so. For me it gives me a thrill to have spent time digging into the Who, What, Why, When, Where and How of a topic that seems steeped in myth and often remains unexplained or unexplored. One amateur shared that they'd made their first HF contact from Perth to Romania, one had gotten their license this year after procrastinating for 30 years, another came back to the hobby after being away for a decade. There was an amateur who managed to set-up a rotatable Yagi on 6m. There were a couple of amateurs who have each been building a repeater network, another who built a 6m Yagi antenna and pre-amplifier, another who erected their tower after 5 years, another who managed to get an article published in the national amateur radio magazine, another who set-up their G5RV and connected it to an Air Spy to make WSPR spots after only a year and a half in the hobby. One amateur got their license upgrade and is looking forward to learning CW next year, another got their station fully set-up and returned to being an active radio amateur. There was an amateur who managed to get through a 20m SSB pile-up. A friend told me that their achievement of the year was to listen, both to others and themselves. There was an amateur who used 10 Watts to make a contact between Massachusetts and New Zealand, one who worked the SO-50 satellite with a Baofeng radio and a rubber duck antenna. One amateur managed to work AO-92 with the same type of gear, made two contacts and even has a recording from one of them. One amateur celebrated the arrival of their Bengali key, considering it Christmas before Christmas. One amateur who made their first contact between Texas and the Netherlands used a 20m self-built Moxon beam constructed from wire and fishing poles. There was an amateur who got their license and is impatient to get on air, it's been a week of waiting. One person upgraded to the top license class and actually started operating. One aspiring amateur was inspired by how easy it was to get licensed and is planning for their entrance as a licensed ham in the new year, mind you, that did't stop him from listening and decoding a NOAA satellite image using an RTL dongle. One amateur decided that he just couldn't wait for his license, studied three days and passed his test. He's now building his first radio, looking forward to making a contact. There's an amateur who joined the ranks and is now looking forward to going for an upgrade to his license next year. One ham has been licensed for 10 months and is already having a blast, erected his first real tower and now has a VHF antenna at 60ft, that's 20m up in the air. There's one amateur who has been learning about what a cheap RTL-SDR dongle can do with SDR# and he's saving up for an Icom 7300. He's finding it tough to balance between spending his money on high-end audio and saving for his Icom. Take it from me, the radio wins, every time! I've only scratched the surface of the activities undertaken in the past 12 months, but it's clear that being an amateur is a positive experience for many people, getting on air and making noise, learning, having fun, trying things and exploring this wonderful hobby is ingrained in much of the community. Before wrapping up, I'd also like to credit Will VK6UU for independently asking the same question and for the countless amateurs who responded, many of whom I wasn't able to squeeze in this time around. Perhaps I should do this more often. What's your proudest moment in the past 12 months? Let me know. I'm Onno VK6FLAB

Foundations of Amateur Radio Recently I managed to get some quality on-air time when I participated in a contest. This isn't about contesting. Although I suppose tangentially it is. It was a most enjoyable experience shared with some friends and because we did it at a local radio club, Sunday morning had all manner of visitors joining us for a little social chat, just the ticket for breaking the monotony of calling CQ. Normally when I do a contest I wear headphones, actually it's a headset, that is something over my ears with an attached microphone to capture my contacts without me having to use my hands or move my head towards a fixed location while I'm making the contact. One hour in my trusty headset broke clean in half. They've been with me since 2012 so I was a little disappointed. They weren't cheap. I'm not going to tell you what brand it is, but they're very popular in the contesting community and I bought them based on those recommendations. Given that I now had no headset I immediately went to the nearest social media outlet to ask for recommendations on what to do next and the typical responses included different brands, ways of repairing, better models, those kinds of things. Everything you'd expect from a community which has some experience in creating a headset that actually works within the context of amateur radio. Don't get me wrong some of these suggestions were great but I don't particularly fancy spending $500 on a headset that is suited to listen to glorious HF SSB. If you're not familiar, think long distance AM radio playing music you can barely hear hosted by a DJ you can almost make out. Making a contact using HF SSB is really an exercise in deciphering really bad audio, often with lots of people on the same frequency at the same time, all vying for your attention. Making a contact, a QSO, in that kind of pile-up can be a challenge. The contest ran for 48 hours so in my down time I had to come up with a solution since making a repair within the time available seemed unrealistic, even though I happened to have spare parts somewhere in my shack. As an emergency standby I brought along my mobile phone in-ear headphones. They're lightweight, cheap, and they block out the audio from nearby conversations in the shack. Everything you want in a contesting headphone. I used a microphone on a boom, attached to the desk, but that wasn't ideal, moving your head, looking at the logging screen, operating the radio, from a user interface perspective, it left me wanting. I should add that I prefer to operate a contest using Voice Operated Control, or VOX, that is, setting up your radio in such a way that you don't need to push any buttons to talk, you open your mouth and the radio automatically starts transmitting. Very helpful when you have your hands on the keyboard and the foot-pedal is just out of reach or making your leg tired because you have to hold it up so you don't accidentally key up the transmitter. It occurred to me that I'd never seen this particular use of a headphone in the context of amateur radio. After the contest I went out to find a similarly spartan microphone. I'm still weighing up the options but I think I might have settled on the idea of pursuing headphones and microphones intended for use on a mobile phone, precisely because they are designed to deal with blocking out surrounding audio from both the earpiece and the microphone. As I'm describing this to you it occurs to me that it doesn't even need to be wired, a simple Bluetooth audio module plugged into the radio with wireless mobile phone headsets might just be the ticket. What has been your recipe for success in creating an environment where you can hear a HF SSB QSO in a contest environment without spending half the value of the radio? I'm Onno VK6FLAB

Foundations of Amateur Radio The question that new amateurs most often ask after "What radio should I buy?" is "How do I get the best antenna?". In a household where you're the only antenna affected aficionado the question is likely more along the lines of: "Why do you need another antenna?". The answer is pretty much the same, an antenna is fit for purpose, generally only one purpose. Going from A to B without walking might involve a car. If it's just you, one seat is enough, if your local cricket team is coming too, you might need more seats. If the road is rough, you might need a good suspension and if it's the middle of summer in Australia, air-conditioning isn't a luxury but a necessity. Each of those different requirements varies depending on circumstance and need. There are plenty more variables, fuel, distance, cost, and the deeper you dig, the more choices. Antennas are no different. While cars have an element of fashion, colour, styling etc. antennas are more utilitarian, radio amateurs rarely care about the colour of their contraption, but they do care about cost, construction and performance. Those three variables alone would make for plenty of choice, but we've not yet talked about some other variables that come into play. If you're a licensed amateur, picking the frequency you want to use is obvious and a major factor in the choice of antenna, but if you're not an amateur, that's not something obvious, but you have seen it before. Without going into the physics of how and why, imagine all the antennas you've seen in your life. There's a TV antenna on the roof, the antenna on a transistor radio, an antenna on a car, the antenna on your Wi-Fi modem, a mobile phone antenna, satellite dishes, you might have seen antennas near train lines, on top of traffic lights, on a GPS and on a satellite phone. You might not be familiar with all of them, but enough to know that there is a huge range of different types of antennas. The more you look, the more variation you find. You might think that each of those different antennas was chosen at the whim of the person spending the money, but actually, each of those antennas was chosen for a specific job. Each of those antennas works on at least one frequency, sometimes more and does so taking into account its purpose. Is the antenna for sending, or receiving, or both? Is it supposed to work regardless of where it's installed, or how high off the ground it is? Does it need to take into account interference from a particular direction? Is it meant for strong or weak signals, does it need to have a defined lifespan, deal with a particular wind strength, etc. etc. Answering each of those questions determines the choices made to select an antenna from the infinite variety available. As an amateur, my licence allows me to operate in six different frequency ranges or bands. Technically that means at least six different antennas, just so I can use the frequencies I'm licensed for. Of course I'm only scratching the surface here, since I've already explained that antennas come in many different shapes and sizes, each with different characteristics and trade-offs. So next time you wonder why so many different antennas, that's why. If you've been wondering when I'll answer the bit about the best antenna, you should already have a clue by now, but the real answer is unsurprisingly: "That depends." "On what?" you ask. On which ever variables you care about and to which degree. The best antenna depends on the questions you ask. Ask better questions, get a better antenna. I'm Onno VK6FLAB

Foundations of Amateur Radio The other day one of my non amateur friends asked for some help. He wants to set up a receiver for his bush fire brigade that's available via the internet so his community can listen to the communication channels when there are fires around, or when a volunteer is out of radio range but still wants to hear what's going on. His question was about hooking up an antenna. We started to discuss what he already had and it turns out that he has enough coaxial cable in either 50 Ohm RG58 or alternatively 75 Ohm low loss quad shielded satellite TV coax. He's not an amateur, won't be broadcasting and just needs it to work without spending too much money. We then started talking about antennas and he had a tuned whip and a generic scanner antenna. Turns out that the tuned whip was for 78 MHz and he needs to listen to 164 MHz, so I suggested the scanner antenna, so called broadband, but no actual specifications. Then we talked about how it was going to be mounted to his metal roof. Tek screws to the iron, a CB mount with solder pads. That started a conversation about waterproofing and coax rot, termination and then the ground plane. I could get my antenna analyser out, drive to his place an hour or so away, help him install and test it and then decide that we need other options. We might still decide to do that, but it will be driven by what happens at his installation. If you're a licensed amateur with a little experience, this story will leave you with a whole lot of but, but, but. If you're not, then you'd come away with, that's pretty reasonable, let's go. What I find fascinating is the gap between those two. On the one hand you've got knowledge that says this isn't ideal, who in their right mind would hook up a random antenna without the proper ground plane with an unknown feed point impedance to a 75 Ohm coax, using solder pads on the top of a roof. There's more of course, but those are the big ticket items. On the other hand you have an antenna, coax, connectors that fit and a high likelihood of noise coming from your radio. I'm not going to pretend that the choices we made over the phone are the final ones, or that it will even work as described, but we discussed that and the selection of parts gives us the highest chance of success, and rather than give the right answer we went with the closest we could get without spending a cent. The gap between knowing and not knowing can be perilous, but it can also be used as a map to navigate from one to the other. Is this going to work? Who knows, too many variables to be certain, too many unknowns. Sometimes ignorance is bliss and sometimes knowledge is a burden. Finding the balance is a lifetime of learning. I'm Onno VK6FLAB

Foundations of Amateur Radio In our hobby there is a term "Elmer", referring to someone who helps new amateurs find their way inside the community, locate resources, understand techniques, etc. It's part of what we might consider the folklore of amateur radio. I started this with the intent to quickly introduce the concept of an Elmer and then spend some time talking about our own role in this adventure, but as is often the case, I was side-tracked by my own investigation. There is a push within the community to abandon the concept of an Elmer, that it's not real that it serves no purpose and that it's a recent invention and irrelevant to our community. Finding an Elmer today appears to be hard work, seeing the wood for the trees, finding a unicorn in this social media connected world. But as it turns out, Elmers are closer than you think. With a little searching, the person who is credited with introducing the word Elmer into the amateur radio vocabulary was Rod W9BRD. He was the author of a column "How's DX?" in QST magazine from 1947 through to 1978. In March of 1971 he wrote: "[t]oo frequently one hears a sad story in this little nutshell: 'Oh, I almost got a ticket, too, but Elmer, W9XYZ, moved away and I kind of lost interest.' Sure, the guy could have burned through on his own, maybe, but he, like others, wound up an almost-ham. No more Elmer. We need those Elmers. All the Elmers, including the ham who took the most time and trouble to give you a push toward your license, are the birds who keep this great game young and fresh." Rod was first licensed in 1937 as a 14 year old. He became a silent key in 2012. On the face of it we have this idea that an Elmer is someone who helps you get your amateur license, but it started me thinking. What if Elmer wasn't a phrase, but a reference. The name Elmer is a male name from Old English, meaning "noble" and "famous". What if W9XYZ wasn't an actual callsign, but an example, given Rod was licensed as W9BRD, it would be simple to think of XYZ as a random suffix, much like I might use VK6XYZ, which happens to be a non-existent call at the moment. What if Rod was saying: Oh, I almost got a ticket too, but Peter VK6LB, or Paul VK5PAS or Mary VK4PZ, moved away and I kind of lost interest. Instead of using real amateurs like I just did, Rod wanted to use a generic name, someone "nobel" and "famous", with a generic callsign to not single out a particular person. The reference to "Elmer" takes on a whole different meaning. It means anyone, you, me, the amateur at your club, anyone who can help another person become an amateur. As it turns out, "Elmer" is all of us, it's a way to refer to anyone and everyone, it's not a specific role or purpose, it's the invitation to you to help another amateur. This of course means that you need to step-up. You don't need to put on your Elmer cape and become a superhero, you just need to be part of the community, to ask questions, to help with discovering answers and to encourage investigation into this exciting pursuit of amateur radio. So, are you an Elmer and if not, what are you going to do about it? I'm Onno VK6FLAB

Foundations of Amateur Radio The other day I read a message from Theodore KS5I who has been around the block a couple of times. He recalls the excitement he experienced when he was first licensed in 1967, the year I was born. He described that at the time transistors were just coming into their own and it was so wonderful to be learning about them. The closing sentence sealed it for me: Theodore wrote: Perhaps, its time for some of us more mature operators to release the past so our hands are free to grab hold of the future and share the enthusiasm of those who look ahead with the same hope and excitement that we had so many years ago.. It's that level of enthusiasm that our hobby needs to foster and develop. The landscape we live in is changing all the time, but new adventures are always just around the corner. They might not look like what was available 50 years ago, or last year, or even yesterday, but they too have their place in the pursuit of amateur radio. Learning is a lifelong activity. If you stop learning, you - as Theodore eloquently puts it - just die. Learning can be scary. Educator Eduardo Briceño talks about the learning zone and the performance zone. The learning zone is when the goal is to improve, concentrating on what we've not yet mastered and the expectation is that mistakes will happen. The performance zone on the other hand is when we do something as best as we can. We concentrate on what we already know and try to minimise mistakes. Amateur radio can operate in either of those zones, doing a contest and going hard can be a performance zone activity, do what we do, do it fast and avoid mistakes. We could also see our activities as a learning zone. We try new things, some will work and some will fail. If we're doing a contest as a learning activity, what skill do you want to master? Is it handing off the QSO, taking the log, recognising a callsign, knowing the CQ zones, matching prefixes to countries and antenna directions, picking the right band, managing battery life or recognising the band conditions? Pick one of those skills and try different things, expect mistakes and learn from them. Over time the thing you practised will be a new skill you've mastered, ready for use when you're going hell for leather in the CQ WW making contacts left right and centre to the envy of your peers. Of course, this doesn't just apply to contesting. For me it's currently about electronics, about figuring out how stuff works and how to apply that to my shack. For you it might be something else in the myriad of options that the 1000 hobbies that amateur radio represents. Life is about growing. Amateur radio is a journey, not a destination. Closing off your options because valves are no longer in vogue and Allstar isn't real radio is just a recipe for stagnation. If you have a dozen minutes to spare, check out Eduardo Briceño's TED talk: How to get better at the things you care about One final point. If you're new to this adventure, your license still wet, then you don't know what you don't know, so you'll spend lots of time in the learning zone. Don't be afraid, it's a great place to be and a wonderful way to explore the hobby in all its variety. I'm Onno VK6FLAB

Foundations of Amateur Radio Imagine a world where electronics are pervasive, a transceiver can be purchased for the price of two Big Macs, kits are designed and built using simple tools at home, software makes it possible to invent new methods of communication on an almost daily basis, where long distance contacts are made throughout the day using milliwatts while ionospheric propagation is at an all-time low, where national parks and peaks are being activated at an increasing rate, where new people join in every day, where it's easier and easier to obtain a license and where the word geek is held as a badge of honour. That world is here, it's now and when Rex, KE6MT writes that we're in the midst of a golden age of amateur radio, he hits the nail on the head, or should that be fist on the key? It's easy to notice that amateur radio is difficult, that it's big, that it's messy, that it's full of know-it-alls, but it's hard to remember that it's fun, that it's rewarding and that every day more and more people join in and enjoy this hobby. The ideals of investigation and exploration are alive and well and the urge to participate in activities, just to get out of the house and see some daylight is strong. While you're in the midst of a revolution, it's hard to see the wood for the trees, but make no mistake, the revolution is here, today, now, and you're smack bang in the middle of it. Today you can go online and find any number of different amateurs who share their skills and knowledge, you can find manufacturers and suppliers at the tap of a screen, find and draw schematics, order custom circuit boards at the click of a check-out button, print an enclosure in your bedroom using plans that you downloaded or designed minutes before. With the digitisation of amateur radio comes the promise of new adventures, with adaptive modes, with encoding and decoding in new and interesting ways, with the ability to hear what your station is producing by logging into a remote receiver anywhere on the planet, by sending messages to satellites overhead and talking to people in another country using a hand-held VHF radio. For some the loss of the valve radio is the loss of history, for others it's a sign of progress and improvement. The inventors of spark-gap transmitters were no doubt put out by the arrival of the valve when that became commonplace. Similarly, the transistor has essentially gone the way of the Dodo in the arrival of cheaply programmable integrated circuits. Our hobby keeps getting bigger, all the time. We didn't abandon valves or transistors, or the spark-gap for that matter, we improved on them. You can still build a spark-gap transmitter if you feel the urge, or ferret out a valve or two and build them into something wonderful, nobody is stopping you. Today we learn Morse Code because we want to, not because we have to. We introduce new people with new technology, new ideas, new innovations and hope that they pick up the cape to become the next superhero. You can bemoan the death of the hobby with the solar cycle at an all time low, the entry of stupid amateurs who need to learn from their betters, the passing of the valve and the abolition of Morse Code requirements, or you can celebrate the appearance of all the new and shiny toys that arrive in our hobby every day. The Golden Age of Amateur Radio is Now. I'm Onno VK6FLAB

Foundations of Amateur Radio There are people who ask questions and there are people who answer them. Sometimes the people who answer even know what they're talking about, but sometimes they just repeat what they've been told without any form of critical thought. The reason I raise this is because when you're a new amateur with a shiny new license, you're like a little puppydog, going from tree to tree to have a sniff. Does this smell good, what about this, ooh, that's a nice smell, I wonder what it tastes like. Puppydog analogies aside, as a new amateur you're filled with questions and uncertainty. You don't know what you don't know, you don't know how much you don't know, your license is still wet, so even if you know something, it might not be true. Interestingly the more I look at this, the more I find that new amateurs, filled with questions are more likely to dig around in the fundamental understanding of things and learn something along the way. I've been around this community for a little while now. I obtained my license in 2010. I've learnt a lot of different things about this hobby, how it works, what the mechanisms, phenomenon, etiquette, physics and so-on make amateur radio work. Most of the time I'm learning about some or other new thing. Right now I'm learning about what a Vector Network Analyser is and how it works, so I can explain it to someone else. Foundations of Amateur Radio is about how stuff works, much like Joe Kaufman's book - What makes it go? Though I read it in Dutch when I was growing up - Hoe zit dat in elkaar? There's another series of books by David Macaulay that are my inspiration, The Way Things Work, Unbuilding, Underground and Motel of The Mysteries to name a few. It seems that my drive to ask questions is fundamental to my existence, my uncertainty doesn't scare me off, in fact the opposite is true, it gets me asking more questions, learning more things, gaining a deeper understanding and finding out more than I ever dreamt was possible. If you're a new amateur, I'd recommend that you attempt to keep your curiosity alive. When you're faced with a fact, question it, attempt to discover what is underlying the response. There are amateurs who think that to ask the question, Why is the length of a dipole calculated using some random constant? - is the equivalent of heresy, lack of skill, incompetence and the source of much derision, when it's clear that even a cursory search reveals that not only is the notion incomplete, it's wrong for most, if not all, examples. My perspective is a little different and I'll admit that for some it might be confronting. Why is it so?, What makes it go?, How come? and Why? are all questions to live by. You might conclude that a world where there are no certain answers is a scary place, but for my money the opposite is true. Just because you think it's simple and answerable, doesn't make it so. If you walk in with your eyes open asking questions, then you'll be much more prepared for an unexpected response. If you've just obtained your license and you're not sure about something, ask. You might not like or understand the answers, but that is just a recipe for more questions. Don't be deterred by those who provide certainty, the more certain they are of their answer, the more you should ask. Amateur Radio is about experimentation, it's a license to play, a license to explore, it's a license to investigate. For me Amateur Radio is encapsulated in a quote attributed to Albert Einstein: The more I learn, the more I realise how much I don't know. I'm Onno VK6FLAB

Foundations of Amateur Radio Get on air and make some noise is a phrase I use often to encourage amateurs to be active on-air and use the bands that are available to us. One thing that's often glossed over is how to actually make that noise. It can be scary to make that first contact. If you've got your radio installed, your antenna erected, your operating position set-up just right and you're ready to actually key your microphone, how do you do that and how do you get the attention of those around you? First things first. You need to establish if your radio is actually working as expected. If you're using a UHF or VHF radio, often the simplest way is to find a local repeater, key-up your radio and give your callsign. The result should be at least a carrier, a beep or a callsign in Morse-code. Some repeaters even have a voice ident, so you can hear that your action of keying the push-to-talk had an effect. If that isn't working, then there are lots of things you can troubleshoot, but that's for another day. If you want to do the same on HF, unless you happen to be in a position that there is a repeater within propagation distance, generally only on the 6m and 10m bands, then you're essentially out of luck. There isn't a beep, or a carrier, or a voice-ident to be found. This means we have to solve the problem in a different way. First of all, if you cannot hear any stations, the chances of someone hearing you are slim. So, the first thing to do is to check that the squelch on your radio is set to allow all signals to arrive at your speaker. Then find a band where it's noisy. When I say noisy, find one where there is lots of hiss. Generally speaking an open band, one where propagation is getting a signal to you, makes noise, lots of noise. There are exceptions to this, but for now, find the noise. Depending on how you have your antenna set-up, you need to make sure that you're using the right antenna for the band you're using. Some antennas work on multiple bands, others only on one, it depends entirely on what you have got hanging off the end of your radio. Once you've found the noisiest band, go hunting for beeps, as-in Morse-code beeps, or voices, or digital sounds. Find a signal, find evidence of activity. If you have multiple noisy bands, check them all. You might recall that this is all dependent on the ionosphere, so depending on what's going on with the sun, things will change, sometimes within a minute, an hour, or weeks. Generally there is a difference between day and night and sunrise and sunset, so experiment. Once you've found some activity, you need to find someone to talk to. If the voice you hear is weak, look for a strong one. The stronger the better. While this isn't universally true, it's a good starting experience. Every radio and antenna combination has a sweet spot on where you know that they can hear you, but you don't know yet what that sweet spot is, so trial and error is the way to go. HF is not like the local repeater. The people on HF can be anywhere on the planet. They might be there for the first time, or for the third time that day having been on air for sixty years, it's hard to tell. A good analogy is to think of a sport stadium with a hundred thousand people in it. There are people all around you and you're trying to make contact with one of them. You can pick their frequency, but they're likely to be talking to someone else. You might be interrupting a daily chat, a regular net, or happen upon a contest or a special event station. You don't know which one it is and sometimes you can't hear both sides of the conversation. So, before you key your microphone and make some noise, listen to what is going on. Once you've figured out that the station you're hearing might be amenable to talking, wait for a break in the conversation, key your microphone and just say your callsign phonetically, once. If there's no break, that's a good indication that the other station doesn't want to talk to you, unless there is an endless stream of stations, in which case the going might be tough and you might be there for a while. If the other station acknowledges your call, great, you just made contact. Confirm that you have their callsign and that they have yours, write it down with the time and frequency, then start with exchanging information, start with a signal report. In the beginning, less is more. Your first name and city is often more than enough. All we're doing is establishing that we can talk to someone and that they can talk to us. Don't overdo it, get a feeling for what's going on. Then do it again. And again. Before long you'll have some experience on how to get on air and make some noise and you can start learning about improving your skills, becoming familiar with your radio and being an active amateur. Hopefully that wasn't so scary, and remember, every amateur had to make their first contact one day, even those who have been on-air for longer than you've been alive. I'm Onno VK6F

Foundations of Amateur Radio Mistakes are common in all aspects of life. Sometimes they are only known to you, other times they are public knowledge and open to ridicule and lambasting. Getting on air for the first time is an accomplishment and often the initial source of mistakes, mishaps and great frustration. Once you've made it on air, the reception to this feat is often underwhelming, people around you don't appear to appreciate the amount of effort you went to in order to key your microphone and for others to be able to hear that. If you've been in this community for a while it's easy to forget what is involved to make that first contact and to dismiss those around you who've managed to obtain their license, acquire their equipment, install and configure it just so and to actually achieve the first visible milestone in their amateur radio journey, though technically it's audible. If you've never done this, or if you have but have delegated it to the historical backwaters of your mind, here's an outline of some steps and mistakes along the path of making your first contact. The first question you're likely to ask is, which radio followed quickly by, from where? Then, if you're like me and many other starting amateurs, you'll have set up your radio for operation on the local 2m or 70cm repeater, you're likely to have some kind of vertical antenna with the microphone gain and squelch set just so and have your radio set for FM. I'm skipping over power, the electrical type, but that in itself can be a feat of endurance. After hunting around for a list of relevant frequencies, you might also have set up something like CTCSS to ensure that your signal actually gets acknowledged by the repeater. If that's not enough, you'll also have made your radio use an offset which makes it receive using one frequency and transmit using another. There's possibly more things you've had to do to make this work and not be subjected to the ire of the local repeater troll who appears to delight in telling you off when they feel you've done something wrong, like leave the roger beep activated or some other infraction. If you did manage to achieve all these things and actually made your first contact on the repeater, congratulations and welcome to the hobby! Take a breath, you did well. After a while you're likely to become more familiar with your radio and start exploring the local bands. You might program another repeater into your radio and even experiment with local simplex frequencies. Each of these activities brings a new experience and new mistakes. For example, not all repeaters use the same offset, or even an offset in the same direction. Not all repeaters have the same CTCSS requirements. If you're using a simplex frequency, remember to turn off the squelch - don't ask me how I know - so you have a chance to actually hear the other stations, even if you are using FM as the mode. The process of getting on air as a first time user can be daunting, with many different points of failure along the way. Ignore the trolls, try your best and ask for help if you get stuck and celebrate your accomplishment when you manage to make a contact. My point is that achieving all this isn't trivial and it would be helpful if that's remembered from time to time. It's easy to dismiss an achievement made by another, but much more rewarding to celebrate it. I'm Onno VK6FLAB

Foundations of Amateur Radio The other day I did an experiment. I searched for "dipole calculator" and using the first 20 results I calculated the length of a dipole suitable for 7.130 MHz. I chose the frequency for no other reason that there is a 7130 DX net every Monday, Wednesday and Friday and for the longest time I've been unable to participate due to the lack of a HF antenna in my new shack. So here's some things I learnt from doing this experiment. Depending on which calculator I use, the length of my dipole can vary by over a meter from longest to shortest result. Depending on my desire to use metric or imperial measurements, my dipole will be a different length, because of course electrons move at a different speed if you're not using the metric system. In case you're wondering, 1 inch is defined as being exactly 2.54 cm, so there's plenty of opportunity to vary that. Speaking of standards, we all agree that the speed of light is a constant, right? Turns out that for some calculators, you can change the speed of light. I'll skip over the notion that none of the calculators actually show what they're using as the speed of light and move on to other interesting discoveries. Apparently you can determine the length of a dipole down to the sub-atomic length, with one calculator going down to the size of an electron to indicate how much wire you should cut from a spool. There are forms that make doing the calculation really easy, single box to type in the frequency, so the answer must be right. There are some that use random standard numbers, even a text book example that uses some number, but no indication where it comes from. For example, the number 486 features regularly, but so does 150 and 5905. There are forms that provide you with several boxes, but no indication which box needs what value, so your answer may or may not indicate the number of eggs per chicken per parsec. One dipole calculator result is actually for a vertical, so your search engine helping you might not actually give you the calculator you expect. There are percentage correction factors. 5% seems to be a favourite number, but no indication as to what the origin of that number is. There's a calculator that allows you to specify the feed point impedance, not sure how that works, but it's a nice feature to have when you're calculating the length of your dipole. Not. One regular instruction is to cut long, that is, measure your wire and cut it longer than the calculator states. How much longer is left as an exercise to the reader. Should it be 1 mm longer, 1 cm longer, or should it be 1 m longer and how much should that change if the frequency changes? Let's move on. The word ground features heavily in these calculators. The phrase "average ground" does too. No indication as to what makes an average ground, or how to go about determining what changes if your ground isn't average. We all agree that the dipole should be half a wave-length above the ground, right? How much is that? The same wave length as the length of the dipole we've just calculated, or a different one? How does the length of the dipole vary if the height varies? While we're looking at variation, how much variation is there depending on how thick the wire you're using is and what about insulation? None of those things are even mentioned in any of these calculators. Dipole calculators, wonderful invention, shame about the implementation. I'm Onno VK6FLAB

Foundations of Amateur Radio One topic that is longer than all other topics combined is that of antennas. Designing, planning, sourcing, building, tuning, using, you name it, all of this is regular fare in the day of a radio amateur. I've discussed the topic here regularly and no doubt I'll revisit that when the mood or necessity takes me. One topic that is rarely discussed is that of failure. About six months ago I moved house. I've been rebuilding my shack, doing all manner of fancy shuffling of gear and yesterday I finally got to the point of getting some HF activity happening. During that process I went through boxes and boxes of stuff, with coax, connectors, wire, nuts, bolts, heat shrink and all the other necessities of being a member of an experimental hobby like ours. One box contained wire. You know the adage, only two types of wire required in our hobby, cheap wire or free wire with a preference for free. This box was stuffed with wire. Bits with connectors, bits wound around spools, bits in zip-loc bags with labels, bits of random length - lots of bits of random length. There was even an abortive attempt at labelling dipoles for various bands on the outside of a couple of zip-loc bags, but no idea if the bit of wire in the bag was actually ever tested and resonant on whatever band was on the label, so who knows, they might have just been cut long waiting for another day and another set of experiments and measurements. I needed around 50 meters of hook-up wire for my HF antenna experiment and it occurred to me when I was hunting through my box that I couldn't look at a spool and tell you how much wire there was. I did a dodgy measurement of one bit, put it on the kitchen scales and determined that another spool was heavier, so it was likely longer, but without bringing in my calculator, doing extra measurements and doing some head scratching there was no way that I was going to get to the point of knowing how much actual wire was on that spool. In the end I made do with the dodgy piece, soldered some joins, that's a whole other adventure, involving a gas-powered soldering iron and a flame, the flame won, as well as several other breaks and fixes. While I was in the process of putting up my new antenna experiment it occurred to me that part of the process of experimentation, even of shack maintenance should be the documentation stage. I have bits of terminated coax, some of it 20 meters long, some longer, some shorter. How much longer, and how much shorter you ask? No idea. But wouldn't it be great if I could put my hands on a piece of kit that I needed that was the length that I expected and not 10 meters over length, or 1 meter short. In my audio kit, I have started labelling patch leads with their functions, using key-ring tags. I don't expect that to work for plain wire, but it should be a good solution for coax. I could use cable tie labels, but past experience with those leaves the text fading on the label. I've experimented with a printed label with clear heat shrink, but for reasons best known to chemists, the clear heat shrink becomes yellow in short order leaving the label unreadable. I've heard of people using electrical tape with colour coding, perhaps one ring for every 5 meters of length, but they seem to come undone in the dust when you go camping. One thing I do know is that this is a recurring problem for me. This is the first time I've actually stopped to talk about it and perhaps it means that I'll get a little closer to a solution. I'd love to hear what you do to deal with this and how you keep track of the countless different lengths of wire, coax and rope that's lying around your shack. I'm Onno VK6FLAB

Foundations of Amateur Radio One of the often repeated attributes of noise and antennas is that man-made noise is vertically polarised and that is why a vertical antenna sounds noisier than a horizontal dipole. It's an interesting thing to say, but it it true? Let's start with what constitutes man-made noise. Cars driving past, solar panel inverters, pool pumps, high-tension power lines, garage door openers, broadband internet modems, LED lights, lawn mowers, leaf blowers, plasma televisions and so on. The more you think about this, the more noise makers you discover. So, are these noise sources all aligned in the same way, making the same noise? Clearly not. There is no alignment standard for installing a lamp, how to align your lawn mower, which direction to drive, what angle to point your garage door opener, so the statement that man-made noise is vertical is clearly bogus. That doesn't mean that the rest of the statement is also wrong. A vertical antenna in an urban environment often sounds much noisier than a horizontal one, sometimes by several dB. So what's going on? One suggestion is that the difference lies in the antenna itself. What if both noise sources, horizontal and vertically polarised were the same, but the antenna heard them differently, how would that look? For starters, a horizontal dipole has a higher sensitivity at a higher angle than a vertical antenna does. So anything arriving at a low angle is picked up by the vertical, but not by the horizontal dipole. The noise that we're talking about is local, we'll get to why in just a moment. Being local, it gets to the antenna via ground wave propagation rather than via the ionosphere. I claimed that the man-made noise we're discussing is local. It's not all local, but if it's remote, it's coming via the ionosphere and we know that it arrives at whatever angle it pleases, so there is little or no difference between a vertical and a horizontal dipole from a noise perspective for signals arriving via the ionosphere. There is another effect. Attenuation or signal loss. In this case loss of strength. Specifically noise strength. More attenuation is the same as more signal loss. Combining ground wave propagation and attenuation brings us to another difference between a horizontal and a vertically polarised noise source. A horizontally polarised ground wave experiences more attenuation than a vertical one. This means that noise that is local travels further and is louder when it's vertical, compared to when it's horizontal, sometimes the difference is over 20 dB. I've been talking about horizontal and vertically polarised noise, but what if the noise is coming at an angle, like the random noise makers around you? A simple way to think of it is that every angle has a horizontal and a vertical part, in much the same way as a right-angle triangle has three sides, one horizontal, one vertical and one on an angle. Putting this all together, we have a number of different effects, all conspiring to make the vertically polarised part of noise travel further, be louder and received better by a vertical antenna, compared to the horizontally polarised part which doesn't travel as far, is softer and heard less by a horizontal dipole. One more thing. The isolation between vertical and horizontal polarisation can be as much as 40 dB, so a horizontal dipole won't hear vertically polarised signals well if at all and vice versa. That doesn't make the vertical antenna useless, far from it. It's great for transmitting a long distance signal, it's small, simple to set-up and if you're in a quiet area, away from noise makers, around 500m to a kilometre or so, it's just fine as an antenna. It also doesn't need to be erected half a wavelength above the ground, doesn't need any sky-hooks, is omni-directional and in common use for most local mobile communications, so don't write off the vertical, just because it sounds noisier. All antennas are a compromise between various elements. I've said it before and I'll say it again, likely plenty more times beyond that. The perfect antenna does not exist. We can prove that, so what ever you pick, what ever you think is the most important, that's what you'll start with and select various aspects as you go. A vertical antenna is no worse than a horizontal dipole, it's different. Just like a Yagi is different, or a discone, or any one of the infinite supplies of antenna options. Knowing what the parameters are is the first step. Oh, and if your neighbours complain about your lawn, tell them it's because of your noise-floor. I'm Onno VK6FLAB

Foundations of Amateur Radio The first time I came across the concept of antenna polarisation was a decade before I became a radio amateur. To connect to the internet while driving around Australia I became the proud owner of a portable satellite dish. Portable in the broadest sense of the word, 150 kilos with a dish that's 2.4m high, 1.8m wide, steel base, electronics, power and patience to erect and point. The dish has a receiver and transmitter component that needs to be aligned, just so, in order to be able to have two-way communications using 5 Watts into geosynchronous orbit. The transmit and the receive are exactly 90 degrees offset from each other. One is called horizontal polarisation, the other vertical. The first thing to observe is that if you're using the wrong polarisation, it doesn't really work well. We'll get into what is right in a moment. Depending on where you you ask, the definition of not working well can be as bad as 40 dB loss. Just let that sink in for a moment. If you want to punch through with more power, you'll need to bring 10 kilowatt with you for the receiving station with the opposite polarisation to hear 1 Watt. If you're using a VHF or UHF FM radio in your car, you're likely to have a vertical antenna. The combination of a repeater on a hill and a radio in a car adds up to much more than the the two alone. The line is blurred today because repeaters are very popular and home-base stations are becoming smaller and smaller by the week, so vertical antennas for VHF and UHF at home are today just as common as they are on cars. It wasn't always that way. In fact, in HF, it's almost never that way and if you're a fan of Tropospheric Ducting or long distance VHF, then you'll also shy away from vertical antennas. Let me explain. If you want to erect a HF antenna and you want it to rotate and you want it to be high enough off the ground, you'll build the simplest mast you can get away with. Imagine a HF Yagi. It's got several elements, long to short along a boom, rotator somewhere in the middle. If you mount this Yagi horizontally, your mast will be around half a wave length in height. If you mount the same Yagi vertically, aside from the height discussion - should it be mounted higher or not - now your mast becomes another interfering element within your Yagi. The steel wires that keep your mast standing will also interfere with the Yagi elements and your elements will be closer to the ground where they can potentially cause harmful radiation. So from a mechanical perspective, putting a Yagi on a mast vertically is not trivial. From a radiation perspective you may theoretically get some gain, but adding an element or two will make up for any potential gain that a vertical arrangement interacting with Earth might assist with. There's another reason. The ionosphere. It sounds like a smooth billiard ball, it's drawn as a uniform layer around the earth, but in reality, clouds and their appearance are much more likely to represent the actual surface shapes that the ionosphere presents to your radio waves. A signal coming in one way is unlikely to come out at the other end in the same way and vice versa. That's HF. On VHF and UHF a horizontal signal and a vertical signal when they're used with line of sight are pretty similar, but once you get beyond that, a horizontal signal will travel further, how exactly is a story for another day. If you're doing point to point VHF or UHF contesting, horizontal is the way to go. What about a single HF vertical? It's excellent for a portable station, it is simple to set up, works in all directions, but it means you'll be able to hear all the local man-made noise as well, so find a quiet spot near the beach if you can. So what's the right way? Almost always horizontal, except on cars or when you're on a DXpedition on a beach sipping pina collada and getting caught in the rain. I'm Onno VK6FLAB

Foundations of Amateur Radio The term NVIS, or Near Vertical Incidence Skywave is in my short experience as an amateur heaped with scorn and ridicule. Terms like cloud-warmer come to mind when people discuss the principles associated with NVIS, but that does happen in the context of where I live, that is, one of the most isolated cities on the planet, Perth in Western Australia. NVIS has several advantages over other forms of HF communication, it can be done with low power, there is little or no signal fading, simple antennas work well, it has low path loss, better signal to noise ratios and if you're in a valley, you can still use it. So what exactly is NVIS? In the past I've talked about long distance HF communication. Your radio signal bounces off the ionosphere, bounces back to earth and so-on. Like skipping a stone on a pond, the angle at which your signal hits the ionosphere determines what happens next. In general, shallow is good, steep is bad, much like the plop you hear when you don't hit the pond just right, a radio signal can go through the ionosphere, never to be heard again. NVIS is about hitting the ionosphere at a steep angle, in such a way that it reflects back to earth. Without going into detail, generally you can use 40m during the day and 80m at night with some variation depending on the solar cycle and whom you want to talk to. NVIS gives you communications less than 1000 km away, plenty to talk to everyone in your city and surrounding area. In the case of an emergency that's also likely enough to get out of any emergency affected area, so plenty of excuses to set up and try for yourself. I can start talking about angles, maximum usable frequencies and so-on, but I won't. These all relate to specific circumstances, depend on what antenna you're using, what the ground conductivity below you is and as is typical in our hobby, many other variables. What I can say is that NVIS to NVIS station works best, so if you're going to test this with a friend, it will help if you both set up a similar station while you learn the variation associated with this kind of communications. Now I did mention up to 1000 km, that isn't enough to leave Western Australia, Perth to the border is about 1500 km, but if you live in the Netherlands, you can get to 15 or so countries. Depending on where you are, NVIS will give you different outcomes and what I'm talking about affects each station differently. For me, the attraction of NVIS is solid communications on 40m and 80m, something that has eluded me so far. It also allows for a low simple wire antenna, an inverted vee dipole, two bits of wire strung up on a pole, 6m in the middle 2.5m at the end will get me up and running. Perfect for a field-day, excellent for a local contest and brilliant if you're only using low power as a beginner. Because the antenna is close to the ground, it's pretty much omni-directional. If you set-up an antenna for 40m and then cross that with an 80m antenna and feed them both from the same point, you'll have a configuration that will operate well for 24 hours without needing to move antennas in the dark. I have no illusions that an NVIS antenna will help me make contact between Perth and Japan, but then it's not intended for that. I've spoken in the past about finding the right tool for the job. NVIS is a tool, it has a job and it's very good at doing that. It's not for everyone, all the time, but it's a tool that you as an ambitious amateur should know about. I'm Onno VK6FLAB

Foundations of Amateur Radio A recurring question for people who are not yet, or newly licensed is something along the lines of: I have a friend who is 400 kilometres away, can I talk to them on my hand-held 2m radio? This particular question arrives in different forms, but generally along the lines of attempting to communicate between point A and point B at some or other distance. The responses, on social media at least, less so on-air, are often very technical, or offer the advice to get a license, or to get a clue, or the question is ignored or dismissed. That's not helpful, or fair. The person asking the question has expressed an interest in our hobby and is looking for help. As a basic set of answers, if you're both standing on the ground, you'll generally be able to talk about 5km using your hand-held. Stuff between you like buildings and hills will lower that distance. If you both stand on a hill, you can talk further away. As an aside, you can talk to the International Space Station with a 2m, 144 MHz hand-held because there is nothing between you and it when it's overhead, even though it's 350 km away. If you cannot see between the two, then an intermediate radio, a repeater, can facilitate the connection. It needs to have visibility to both radios at the same time. The higher the middle point, the further the distance. For example an antenna at 350m above the ground has a so-called radio horizon of 77km and I should point out that that's actually 15% further than actual line of sight. As long as both ends are within that radius, you should be pretty much good to go. You can theoretically string together a whole bunch of repeaters, along a road for example, but more often than not, for distances greater than line of sight you need to invoke radio frequencies that your 2m hand-held won't do. These frequencies are generally referred to as HF and is generally anything between 3 and 30 MHz. Radio transmissions on these frequencies mainly use the ionosphere to make contact possible and you can make contacts from as close as next-door, to as far as the opposite side of the world. The ionosphere is subject to weather in much the same way as clouds and rain. The variation in the ionosphere is driven by the sun, not by wind and humidity, and it varies throughout the day as the sun rises and sets. Communication varies depending on where the sun is and several other factors well outside this explanation. As the ionosphere changes, usable frequencies change. Something that worked one moment might not the next because the ionosphere changed. As a licensed radio amateur you have access to many different frequencies and depending on the state of the ionosphere you can change frequency as required to alter your station to suit the conditions. You can think of it as adjusting your sail depending on the wind direction, to get from A to B. One final point. Antennas are many and varied. They are designed for specific purpose and will react differently depending on how they're designed, built, installed and used, so the variation you're stepping into is enormous. This hobby is nothing like dialling a phone number and making a connection, it's all about the experience and the learning. If that tickles your fancy, you're already halfway to becoming an amateur. Welcome. I'm Onno VK6FLAB

Foundations of Amateur Radio Morse Code is a way of communicating with people across the globe using dits and dahs and the spaces between them to convey a message. It's no longer required to get an Amateur License, but that doesn't mean that it's not useful, in fact, far from it, Morse is still heavily used in this hobby. I've been attempting to learn Morse code for quite some time. To do this I was told, time and time again, over and over, ad nauseam, that Morse is an Auditory Language. I was told that the way to success was to listen before sending, to be able to decode before ever touching a key and to learn with tapes. I also was told that if I learned it slowly, I'd run into trouble later on when I wanted to hear a beacon, which identifies itself with much faster Morse Code. Morse is an interesting phenomenon. We describe it in words in day-to-day terminology as having dots and dashes, which is how the International Telecommunications Union, the ITU defines it, but I have been assured that I should think of it in terms of dits and dahs, because that more closely mimics the sound of the language, and from my current experience, I have to agree. This is an audio language and it's defined in terms of how long a dit takes to transmit. A dit is one time unit. A dah is three dits. The space between a dit and a dah within one letter is one dit. The space between two letters is three dits and the space between two words is seven dits. I'm not expecting you to learn that right here and now, just pointing out that there is a definition of how this is supposed to work. If you make a dit last longer, everything else lasts longer, so determining how fast you're sending something is not simple to do, unless there's a standard. Of course there's a standard. The way that the speed in Morse is defined, is by counting how many times a standard word can be sent per minute. The Paris standard uses the word PARIS, because it is precisely 50 dits in terms of timing. There's another word, CODEX, which has 60 dits, so the two Words Per Minute are different depending on which standard you use. And to make things even more interesting, some people measure with 5 dits between words where the ITU specifies 7 dits between words. So, speed is variable, depending on who's measuring. The ITU doesn't specify which is right, but it gets better. As I said, this is an audio language, so you need to listen to it to learn it. Over the years it's been hammered into me, don't write Morse, don't use dits and dahs, listen, listen, listen. I did. At 25 Words per Minute, at what ever standard that was calculated, I can now hear Morse, that is, I can detect the gaps between letters and words and I can hear the rhythm of the code. Great, so I'm done, right? Not so fast. While I can hear the individual letters, I still don't actually know what a G sounds like, or what makes the letter X, or an Open Parenthesis, or a Question Mark. Easy, look them up, learn the sound, done. Morse Code is standard, right? Right? Seriously, Morse Code is standard, right? No. Not so much, not even a little bit. If you search the globe for Morse Code Charts so you can look up a Question Mark you'll end up with hundreds of different charts. Everyone agrees the letter A or Alpha is dit-dah, but they cannot even agree that N, November, is dah-dit. Some show the difference between an open and a close parenthesis, others use the same character. There's charts that put dits-and-dahs inside the letters of the alphabet, but don't specify in which order the parts are heard. The Wireless Institute of Australia doesn't even appear to bother specifying, the FISTS Down Under Morse Preservation Society doesn't show a copy, the ARRL has an abomination on their website that you cannot even link to, the ACMA defines the end of transmission as a cross and then there are the special ones, survival charts and power point slides and using words to describe a symbol, so you can know that a fraction bar is a dah-dit-dit-dah-dit, but you don't actually know what it looks like. You'll be pleased to learn that the ITU actually publishes a document, ITU-R M.1677-1, last updated in October of 2009, that specifies the International Morse Code. It goes into great detail on what characters are defined, how to start and stop transmissions, how to transmit things like percentages, what to do if you need to send a multiplication symbol, inverted commas, minutes and second signs, fractions and as a bonus it has the phrase that this document and I quote: "should be used to define the Morse code characters and their applications in the radiocommunication services". Nothing quite like a standard that should be adopted, rather than must be adopted. The ITU also tells us that "the code needs to be updated from time-to-time to meet the needs of the radiocommunication services". The French word "arobase", which in English is pronounced "at" and looks like the letter a with a circle, used today in an email addre

Foundations of Amateur Radio In the past I've talked about a weekly net I run, called F-troop. It's intended to be a place where new and returning amateurs find their feet, have a chat, test their gear, meet new friends, ask questions and sometimes get answers. If you want to come and join in, you're welcome to and I'd love to meet you. This net came about because I was new to the hobby and didn't find anyone running any on-air activity for people like me. I asked around and with some encouragement I decided to start an activity. Just like that. My point is that you can do the same. You can keep looking for that elusive group of people who share your interest, or you can get on-air and start a conversation. There's no forms to complete, there's no rules about how it has to happen, no expectations about how you run your net, just have at it. F-troop today looks nothing like it did on day one. On the first day I was on a simplex frequency and nobody could hear me. The next week I moved to a different day and to a local repeater at a different time. After doing that for a little while, we changed day and repeater again, because we kept running into other activities. I'm mentioning this because what you start today may look nothing like what it turns into tomorrow. Your idea might fail, or it might succeed beyond your wildest dreams. You may find new friends or find a different activity that sparks your interest. You could inspire another amateur to join the community, or encourage someone to get on air and make some noise. All around me there are nets, not in name, but in action. There's a group of people who get together during the week at 6am or so for about half an hour to chat on the way to work. There's a group who are learning Morse, another testing FreeDV, another chatting during the morning breakfast, another in the afternoon. There's a net for the emergency communications team, one for the local repeater group and there's a locally hosted net that attracts interest from all corners of the globe. I'm sure that there are others. I know from personal experience that you'll get callers who might not have much to say, but your presence gives them a reason to turn their radio on and participate, to get out of their house and talk to the world. They might not say much, but your being there might be a comfort. While F-troop is semi-organised, with a website, an advertised time and location, a dedicated host and regular callers, your net doesn't need to be any of those things. It can start as a regular chat that can grow, or it can fade away if there is no interest. Your hobby, your rules. One thing I can tell you is that hosting a net is very rewarding. I've seen amateurs start with very little to say, very unsure of themselves, grow into their license, expand their horizons, become skilled and find a new community to make their own. You don't need permission to start a net, you just need to decide to. I'm Onno VK6FLAB