Foundations Of Amateur Radio

Foundations of Amateur Radio There is an interesting phenomenon that I've begun to notice and now that I've seen it, it's hard to un-see. Think of it as the equivalent of the little dot in the top right corner of the screen that signifies the end of the reel to a movie projectionist. Once you've seen it, you can't miss it ever again. If you haven't, sorry, you will and now you'll carry that with you for the rest of your life. Across Amateur Radio, from Foundation and Standard through Advanced or Technician and General though Extra, there is this thing where people get together and ask each other how to get started. It's amazing to observe, grown adults every one of them, not daring to take the first step. It ranges from keying your microphone for the first time, through to making your first HF contact, through building an antenna, going portable, climbing a mountain, making contact with the International Space Station, doing a contest, building a radio or erecting a tower. It seems that collectively we've

Foundations of Amateur Radio The single largest topic of conversation in Amateur Radio is about Antennas. The discussion often starts with one amateur telling another amateur about some or other amazing antenna, followed by a heated discussion about the merits or pitfalls of that same antenna and why they would never ever consider using it and why it's a waste of money, or some other rationale. Let's take for example the discussion of Dipole versus Vertical. There are those who will tell you that they'd never ever use a Dipole and similarly those who'd say the same about a vertical. Assertions of suitability aside, let's have a look at what we're talking about, first of all. In rough terms, a dipole is an antenna that is generally suspended between two sky-hooks, its fed from the centre and has pretty much an omni-directional radiation pattern. That is, signals arrive and depart from this antenna, pretty much evenly in all directions. Now, before you get all excited. It's not exactly the case, since it's n

Foundations of Amateur Radio Today I'm going to talk about dipoles. You know the tried and true antenna, the go-to design for getting on air, the simple first antenna you ever make, the one you learn from, you know the one. It's the mainstay of every amateur, of any field-day, of all things Amateur Radio. It's a simple thing. Using metric, rather than imperial measurements, but the point stands, you use the speed of light in vacuum divided by the required operating frequency and you get the overall wave length for that frequency. In absolute terms, roughly 300 m/s divided by 50 MHz, gives you 6 meters. Surprise, that's the band name for 50 MHz. Now the dipole is a half-wave contraption, so, 6 meters divided by 2 gives you 3 meters for your total half-wave dipole. Each leg is half that, a quarter wave length, so you have 3 meters divided by 2 again and you end up with two bits of wire, a meter and a half long each. If you're following along, that's 300 divided by 50 divided by 2 divided by 2, or using the

Foundations of Amateur Radio Today I want to raise the topic of batteries. Specifically, sizing the battery. You can do as I did naively, look at the manual, see that the current consumption of your radio is 22 Amp, decide that this means that you need to get a 26 Ah battery to use your radio for 1 hour. Being the portable type, I got two, 52 Ah in total. Some time has passed since I made that purchase. I've learned that I can get a lot more out of my battery than 2 hours. I also learned that lugging 56 Ah around is not fun. Having learned this, what could I have done to improve? Well, first of all, the 22 Amp is for Transmit. According to the manual, on receive it's only using 1 Amp. If you're not transmitting all the time, then you're not drawing 22 Amp the whole time. The ratio between send and receive is the Duty Cycle, often expressed as a percentage of the time spent transmitting. Another thing to note is that 22 Amp is when you use full power for a particular mode and band combination. On my radi

Foundations of Amateur Radio There is a recurring topic in Amateur Radio circles, called "permissions", or "rights", or some other word indicating "entitlement". It's a conversation that has been happening since the dawn of radio experimentation and will continue until well after our Sun has burped it's final sun-spot. In Australia, there are three classes of License, in increasing level of responsibility they are Foundation, Standard and Advanced. There is an ongoing tension between these categories. Some higher level responsible licensees look down on the class with less responsibility, and the reverse is also true. This separation of class is an evolutionary one. As I said recently, the most recent overhaul, more than 10 years ago, back in 2005 saw the introduction of the Foundation Class and the consolidation of various classes into Standard and Advanced. There are current noises being made about how this needs to change. There are those who suggest that the Foundation Class needs to have access to mo

Foundations of Amateur Radio The history of the evolution of amateur licensing is a nebulous affair, told and re-told, moulded, changed and interpreted by the story tellers along the way. There is an on-going debate about how the restructure of the licensing regime in Australia, in 2005, has affected our hobby. In 2005, after a 10 month review period, three classes of license were established, a new Foundation class, an a re-imagined Standard and Advanced class, using existing novice and novice limited licenses to create the Standard class and combining limited, intermediate and unrestricted licenses into the Advanced class. I've touched on this subject before, back in 2011, when I noted that those who forget history are doomed to repeat it. The ACMA published the review in May of 2004. It summarises the responses about the introduction of the Foundation licensing option. It opens with, "Over two-thirds of submissions were in favour of the introduction". It goes on to say that the most common reason for

Foundations of Amateur Radio There are skills that come from thinking and there are skills that come from doing. There is place for both in Amateur Radio. There is nothing in the world that is like the experience of working a pile-up, unless the trading floor of the New York Stock Exchange counts, but I've not personally been there and it doesn't look as intimate as a radio shack. Working stations across the planet that are coming in thick and fast is an amazing thrill, not unlike getting onto a roller-coaster. The long slow journey to the top of the ride is calling CQ, the crest of the hill is the first response and the loop-de-loop is when they're all calling at the same time; rolling back down to earth at the end of the ride is the petering out of the calls, only to start again. If you've never experienced it, I'd strongly recommend that you find a way to put yourself in the position where you are exposed to this absolutely thrilling experience. So, what do you do when you're actually in this situatio

Foundations of Amateur Radio This is episode 236 or so of my weekly contribution to this hobby. As you may have heard me say over the past few weeks, this is now available as a podcast which you can subscribe to. It's available at http://podcasts.itmaze.com.au and you can also search for my callsign, VK6FLAB on iTunes and find it there. I'm mentioning this because each podcast also contains a transcript, which you can use to search the content. I've been doing this podcast since May 2011 and in that time I've covered many topics. I get wonderful feedback from you about each segment, thank you, and I also get requests for content. Often new listeners ask me if I could talk about XYZ topic, and I'm finding more and more that in fact I have talked about such a topic. That's not to say that I won't revisit a topic if I have information to add. For example, I was in the process of researching baluns, got distracted by word-use and will revisit. As I'm doing the research I'm realising that the rabbit hole goes

Foundations of Amateur Radio Previously I've discussed different aspects of contesting in relation to Amateur Radio. If you're unfamiliar with the concept, contesting is an activity where you test your station and skill against other amateurs. Unlike other contests where you're all in the same physical location, say a stadium, or an online playing field, amateur radio contesting is most commonly done from the comfort of your own shack. Of course, as is true for everything in life, there are exceptions to this. There are contests where you're not in your own environment, say on a field day, at a contest station, or some other place, but I'll ignore these for the moment. In most organised sports, and amateur radio is no exception, there are rules for participating. It should go without saying that you're expected to abide by the rules. Disqualification, bans, even life-time exclusions and revision of results can and have happened. Contests are planned by different people and groups and vary greatly across t

Foundations of Amateur Radio In every new technology there is an ah-ha moment, the single one insight that defines for you personally what this technology is all about. No doubt this happened when Amateurs first used valves, when they started using transistors and so on. For me that moment happened during the week. You've heard me talk about the absurd noise floor, that is, the incredible amount of local radio noise that I experience at my shack. I've been working my station portable to get away from the racket. During the week I came across something that is likely to change that. You've no doubt heard about diversity reception. You can use two different antennas, do some fancy phase switching and make the noise go away. Now I should clarify, at least briefly what that looks like. Imagine throwing a stone into a lake, it makes waves. If you throw two stones into the lake at the same time, the waves get bigger, but if you were to time it just right, you could throw in one stone, then the next. If you time

Foundations of Amateur Radio On a regular basis I receive emails from fellow amateurs and shortwave listeners who provide feedback and ideas about this weekly segment of Amateur Radio. It's a joy to read how they feel that my little contribution encourages them to continue in the hobby, or come back to the hobby, or to build something, or to do something, to participate, to experiment. Yesterday I received an email from an amateur who came up with an idea that's worth sharing. The idea was pretty simple. Encourage every new entrant into our hobby to build a crystal radio. I know that this might sound like a trivial thing, even silly, but for me it makes complete sense. Imagine that, building a receiver and understanding how it actually works. I know I've never actually done that and I suspect I'm not alone. So, here's a thing. Next time you're looking for a project to do, for a thing to make, for some soldering practice, try making a crystal radio. There's opportunity to make it work for CW and SSB - thin

Foundations of Amateur Radio Today I started doing some research on Baluns. It was prompted by a message from a fellow amateur who asked about how they work and what they do and what the difference was between a 1:1, a 1:4 and a 1:9 balun. While doing that, I thought I'd look up what the definition was of a balun. It says right here on Google - so it must be true - that it's a type of electrical transformer used to connect an unbalanced circuit to a balanced one. I clicked on the link that said "Translations, word origin and more definitions", which showed me a history of the use of the word balun and I was hooked. The explanation of a balun will have to wait for another day. I started looking at the use of the word going back to the 1800's, based on Google's Ngram Viewer. Looks like it was used a bit between 1800 and 1910, but steadily declining in use, until it started picking up in popularity around 1930. Today the word balun is more popular than the phrase "radio amateur", but less popular than either

Foundations of Amateur Radio Today we have a world where radios are more and more like appliances. We can buy them at a store, ship them to our location, open the box, plug in the radio to an antenna and start operating. I said, "like" an appliance, because a transceiver is not like a toaster in all aspects and it's those little gaps between the toaster as an appliance and a transceiver as an appliance that I want to highlight. I was with a farmer recently who had a CB radio in his troopie, or if you're not familiar with that, a Toyota Land Cruiser, this one had 400.000km on the clock and was just getting run in. According to the farmer, the CB had never worked right. He joked that it was often easier to yell across the paddock than to use the radio. On a farm there are lots of things happening, during harvesting, heavy equipment is moving everywhere and communications are vital. I was with a friend and the first thing that we noticed about this CB is that it was a UHF CB, that is, it was using 70cm, or 4

Foundations of Amateur Radio Yesterday during dinner I heard an interesting story. Apparently there was a farmer who had a chicken coop that he kept warm at night by using a 240 Volt light bulb hooked up to the chicken wire surrounding his chickens. The farmer's property was in the vicinity of a local AM broadcast transmitter. They only found him because the people in the shadow of the chicken coop had bad reception. I'm sitting at the dining table, listening to this tale and wondering, could it be true? My gut feeling was no, but surrounded by food and friends it was hard to put my finger on precisely where this doesn't add up. A little digging revealed that the transmitter in question was the local ABC 6WF transmitter at Hamersley. So, what do we know about this transmitter? First of all, it's a 50 kW AM transmitter. I must confess, I have operated this station. Imagine that, 50 kW AM, with an introductory Foundation License. Anyway, back to the 6WF transmitter. It's located on a block of land, roughl

Foundations of Amateur Radio Whenever I go out to play radio, which is whenever I actually want to operate, I try new things. For example I've experimented with different clocks, to keep track of what time I made a contact, I've experimented with different ways of logging, with different locations, different antennas, with different bands, times of day, methods of calling CQ, methods of making a contact with a DX station, different methods of looking at propagation, different distances from interference. As I said, every time I try something else different. One thing I do, that might not seem obvious. I try to only change one thing. The reason I do that, is so I have a better understanding on what the change actually did. Of course this isn't entirely possible, you often cannot park in exactly the same spot, at the same time with the same propagation, but if you go out often enough, things start coming together. So, for a clock, I use a $20 digital watch that has two time-zones. I set it to show local and

Foundations of Amateur Radio There are times when you'll find yourself being encouraged to participate in a contest. You might receive an email, a Facebook encouragement, or even hear an item on the local news about a contest. Where do you start if that's what you're interested in? Well, first things first. You need to find out when this contest is exactly. The reason this is important is because you might go though all the preparation, only to find yourself sitting at a family BBQ listening to your favourite family member sharing the story about the dog and the lake, rather than being in the contest. Once you've determined that you are in fact able to participate in the contest, put it in your diary. This seems obvious, but I can guarantee you that there will come a day when you're happily sitting in the sun having lunch when that sinking feeling appears and you realise that the contest you were going to play in started 8 hours ago. Now that you've got the basics out of the way, what's next? Find the c

Foundations of Amateur Radio Today I was looking around my shack and noticed that I have lots of different amateur radio tools that go beyond the simple bits and pieces that I started with, namely a radio, battery, power supply, coax and antenna. While I have no illusion that my gear is complete, or even representative of all of the stuff that you might need or come across, I think that it's worth while to mention a few bits and pieces that you may not have considered. I think the first thing I got that wasn't part of the basic kit, was a dummy load. It's only a little one, rated at 50 Watts or so, but seeing that I'm only using 5, that's more than enough. I use it to check things like VOX sensitivity, that is, I want to set-up a way to talk into my radio without having to push a button - for when I'm doing a contest, and I don't actually want to transmit any signal while testing, so I plug in the dummy load and test with that. I also use it to plug into the end of a piece of coax that I'm testing. I can t

Foundations of Amateur Radio Today I had the pleasure of talking to a group of freshly minted Amateurs. It's a semi-regular occurrence where I visit a local club that offers training to obtain an Amateur License. I should mention that you'll find clubs like this all over the place and there are often opportunities to do remote examinations if you're too far from an assessor. This however isn't about becoming an Amateur, that's something that I'll leave entirely up to you, even if I think that being an Amateur is a wonderful thing. One of the things I like about this hobby is that it's different things to different people. There is a huge variety of aspects to this pursuit of Amateur Radio and as I've said in the past, it's really a thousand hobbies rolled into one. In Australia there are three so-called classes of license, think of it as a moped licence, a car license and a truck license. If you want to drive a truck you need that one, but if you're on a moped, there's no need to spend your efforts on lear

Foundations of Amateur Radio A recurring topic of conversation is propagation. There is learned discussion about sun-spots, A and K indices, forecasts, ionospheric probing, not to mention half-baked guess work from less scientific perspectives. It's been my experience that all these tools are wonderful, but none of them beat turning on your radio and having a listen, or better still putting out a call. So when do you listen and where do you listen? The trivial response would be everywhere, all the time, but none of us has enough time for that. In general, 20m, 14 MHz works most of the time. At night, frequencies lower than 20m, that is 40m, 7 MHz and 80m 3.5 MHz work better. During the day, higher frequencies, 15m, 21 MHz and 10m, 28 MHz work better. Of course this is not a hard and fast rule. As I said previously, there is no such thing as a perfect antenna, in fact we can prove that it cannot actually exist. Similarly, there is no such thing as perfect propagation. We tend to think of propagation in

Foundations of Amateur Radio Today I'm operating portable, in fact I'm operating portable every day. Though I'd have to confess, some days more than others. I have to do this by necessity. There is lots of RF noise at home, so I'm forced to physically move away from the interference and set up elsewhere. You can do this as simply or as complex as you like. I've done it with a bag that contained my radio, a battery and a wire antenna that I strung between two trees. I've also gone portable with my car, camping gear, a trailer full of radio gear, a wind up mast and a rotatable dipole with a generator to provide power. And everything in between. My point is that for every circumstance there is a different set of tools that will solve your problem. Several amateurs I've spoken to are quite unsure about this portable adventure and are not really geared up for such shenanigans even if they're interested to get out and about. So what is involved with going portable? The essence of any station is the antenna