Ham Radio HomebrewA How-to on Making Your Own Amateur Radio Equipment
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Author's note: I originally began this "how-to" around 2003 or so. Since then, while some of the parts I mention below have become obsolete, many now have SMD versions available, which are operationally identical to the listed part. If you are having difficulty finding one of these parts, drop me an email and I'll see what I can do to help you find it. Thanks for reading. | |
"Rig here is homebrewed, OM."Don't get excited, we haven't set up a still, we're not talking about illegal suds here. In the world of amateur radio, "homebrew" is the art of building homemade radio equipment. Whether you design and build it "from scratch" in the basement workshop or garage, or construct a kit of parts on the dining room table, homebrewing equipment is not hard to do, and a double whammy of a lot of fun - you get to use the equipment when you're done building it! I think I have more fun building a piece of equipment and making it work like I want than I do operating. I know what you're thinking... "okay, so it's a lot of fun, but how much will this fun cost?" Not as much as you think! You can spend as little or as much time or money as you want. It's true. You can build complete working equipment, like simple transmitters or test equipment, for less than $10 in parts. Or, $0 in parts if you "scrounge" them from other equipment. So, now if I say I "roll my own," you know I mean I make my own radio equipment, not... that other thing. Okay, let's say I've convinced you, and you'd like to get started. So how do you start? I found the best place to begin building your own radio equipment was by reading books and collecting circuits from magazine articles of equipment others had built. Not to just copy them, but to learn from them, to educate some of that gray matter upstairs. Some of the best books I know come from the ARRL (the American Radio Relay League, amateur radio's national organization). Below, I've listed a book or two, and a few magazines and articles that I have found useful. BTW, these lists are not exhaustive, they're simply the resources I know and like to use. Books
These books, and others like them, may be found at the ARRL website, and at Amazon.com. Magazines
The last four magazines belong to a category called "trade magazines," intended for RF engineers and technicians. I love trade magazines. You can learn as much from the ads as the articles in these things. ArticlesAll of these are from QST, the magazine published by the ARRL.
QST magazine, August 1983, pp. 18-22. Still a great design philosophy, one of my favorites.
QST magazine, November, 1981, pp.11-21. A 5-band, SSB receiver construction project, variations of this article also have appeared in a number of annual ARRL Handbooks.
A 5-part article that appeared in QST magazine:
QST magazine, February 1988, pp.30-32. Full QSK is beneficial and easy to achieve without relays at low power levels.
QST magazine, August, 1980, pp.14-19. This rig is a classic circuit, and has also appeared in a number of ARRL Handbooks. Roy also produces a terrific antenna modeling software package called EZNEC. Check it out.
A 2-part article that appeared in QST magazine:
QST magazine, October, 1989, pp. 25-30. Another favorite of mine, from an ARRL Lab Engineer.
QST magazine, August, 1992, pp. 19-28. IMHO, a ground-breaking article that single-handedly brought DC receivers back into vogue for QRP homebuilders.
QST magazine, January, 1993, pp. 32-40. You could consider this Part 2 of Rick's preceeding article. For ARRL members, these articles may be found as PDF files at the ARRL. What's next? Well,while you're educating your brain, you'll want to educate your manual dexterity by learning how to solder and use tools for building electronic equipment. No reason to wait until you're a pro, just jump right in and build something. Let's see, a soldering iron (or a temperature-controlled soldering station if you can swing it) and some solder, a set of good hand tools, a work table and plenty of light is a must to start. And you'll need at least one piece of basic test equipment. I think a good DMM (digital multimeter) is essential. Later on, after you're more experienced, I'd recommend getting a decent oscilloscope. Everything else you can build if you like. MORE ON SOLDERYou've heard that 60/40 solder is the optimum solder for electronic soldering work. But what does that mean? 60/40 refers to the mixture of Tin (Sn) and Lead (Pb). So, 60/40 solder is 60% tin and 40% lead. And it's just fine for electronic soldering. But with 60/40 solder. there is a short period of time where the solder is between states, not quite a solid or a liquid. It's an in-between "plastic" state. So, I prefer to use 63/37 solder, or "eutectic" solder. "Eutectic" means that there is very little if any "plastic" state when the solder melts. This means the 63/37 solder goes nearly instantly into a liquid from a solid. This also means I can solder just a bit faster. And it ALSO means, if I make a mistake, it's just a bit harder to fix. As far as hand tools are concerned, I recommend getting the best you can afford. If you take care of them, they'll last nearly a lifetime. I personally favor tools designed for electrical or electronic work, from either Klein hand tools or Xcelite by Cooper Tools. Both of these brands are excellent. I currently use quite a bit of Klein tools because they're readily available at most Home Depot stores. Greenlee also makes some excellent tools. What hand tools will you need? I think the absolute basics are:
You'll find that a small vise will be very useful, too. With these tools, you can cut and strip wires, poke holes and cut on metal, and turn fasteners. As you gain more experience building, you'll no doubt want some of the more specialized hand and powered tools available in the world. But much creating and repairing can be done with just the tools on this list. Also, unless you need them for repairing manufactured equipment you may already own, you won't need metric tools, good ol' American SAE will do just fine. The next stop for me was building a kit or two. I liked kits quite a bit, still do. Everything you need in one package. My very first kit was a crystal radio kit my father bought for me when I was about 12 years old. That was neat. Listening to distant broadcast stations in bed at night was great... for awhile. After that small success, I thought I could tackle something more advanced so I purchased a Heathkit HR-10B amateur radio receiver. Those kits from Heathkit were great, they came with all the parts and a book of instructions written so well, you couldn't hardly mess up. I built this receiver in about a week of idle time, but was a bit disappointed when I turned on the power. All I heard was a bunch of garbled voices. Darn, where did I mess up? I took the radio to the local Heathkit store where I bought it and told the service man there what my problem was. He checked it out, and said "except for a few cold solder joints, it works fine." Huh?? It was then that I discovered what "BFO" meant on the front panel. Later, as I gained experience, I tried scratch-building projects from magazine articles, so collecting electronic parts became an activity. I did this for each project as I built them. The first projects I attempted to build this way were messy to say the least. And they usually didn't work. But I kept swinging, and after a couple of successful projects, repeating the parts mining activity became tiresome. So I made a list and built up a supply of commonly used and available parts. Nowadays, I build kits or whip up projects of my own design. Oddly enough, most of the parts I use in my own designs come from my list. Go figure. ;-) And here's the list (* denotes a "must have" IMHO):
As you can see, many items on this list are general-purpose electronic devices and parts. I think that's good, availability is greater for GP parts. If a component fails or I need a part, a GP device is usually available locally. But that's not to say I don't like some of the more exotic devices in the world. For example, I usually don't keep any of the MiniCircuits mixers, MMICs, etc., in stock, but I do like them in projects. Great company, they have all kinds of fun RF items at pretty reasonable prices. You can find these in small quantities from various distributors. A few years ago, I started stocking some surface-mount components, 0603 and larger. And I have received some of the free SMD prototyping kits offered from time to time from Phillips, and I periodically "beg" for free samples from the other semiconductor manufacturers as well. Why not? The worst response I can get is "No." Okay, is that it? No, of course not. For more advanced homebrew pursuits, I use the following software programs:
Some others you can find are Serenade SV, a circuit design suite of programs, and Eagle Lite PCB Editor, for designing printed circuit board layouts. Some version (demo or feature-limited) of each of these Windows programs is available for download for FREE! Some of the books I listed above also come with software that's pretty good, including Smith Chart programs, filter design programs, etc. There, that should get you started. Have fun and don't get frustrated. If you run into a problem or have a question, drop me an email. Homebrew Radio Links
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