Archive for category Ham Radio

My own QSL cards

Posted by on Friday, 17 September, 2010

All (sub)cultures have rituals, and ham radio is rich with them. Before the Internet, the only way to talk to someone in another country was to either (1) get a pen-pal, or (2) pay megabucks to talk long distance. It was thrilling to throw a wire in your backyard tree, solder some circuits, yell into the void, and be answered by a random geek across the sea!

It was such a big deal, in fact, that a whole tradition of exchanging business cards rose up around it. Except it’s not exactly a business card, but more like “I’m a radio geek” postcard. After chatting with a stranger, you send him a card with your callsign, a picture of your city, and a bunch of details confirming the contact (date, time, frequency, signal strength, etc.). He sends the same thing back to you. Then you both hang the cards on your walls next to the dozens of others, a virtual trophy case of how l33t your radio communication skills are. They’re also often the proof required to win certain communication contests.

They’re called QSL cards, and you can read all about them on wikipedia (and see even more examples of them if you do a Google image search. It can be a real art form.

Well, after making a couple dozen contacts, somebody finally sent me a QSL card from Mississippi. So I was forced to design and print a bunch of my own. I’ll be sending my new design back to the guy tomorrow. Here’s what the front and back look like:

(I did the whole thing in Inkscape on Linux, and I’m crazy impressed… it’s just as powerful as Illustrator!)

First homemade antenna

Posted by on Saturday, 11 September, 2010

I take business trips about 6 times a year now — never more than 2 or 3 days at a time. But now that I’m a radio ham, I love to take the hobby with me to random hotel rooms. For the last few trips, I’ve carried a little handheld VHF/UHF walkie-talkie, and this allows me to meet new hams within a few miles radius. But now that I’ve been learning morse code, I’m excited to create a real long-distance setup that I can effortlessly tote in my backpack on these hotel trips.

What are the main ingredients? Very simple:

  • a tiny low-power radio, 5 watts or less (called “QRP” in the ham-verse)
  • a set of morse-code paddles and electronic keyer
  • a portable antenna capable of picking up lonnnnnng wavelengths (like 20 or 40 meters)

The first two things aren’t a big problem; I’ve already been practicing morse code on my paddles, and there a zillion tiny radios to choose from that I can buy. But a portable long-distance antenna? That’s a black art. Luckily I found this very cool site that describes a homemade antenna that folds up into a three ring binder for transport! It’s basically a bunch of parts from Radio Shack and Office Depot, strung together cleverly. After a week, I’ve got it all built. You’ve got two 5′ lengths of wire hanging horizontally, meeting together into a middle connector:

…and each wire end is terminated by a crazy hanging transparency covered with zig-zagging copper foil:

…because the zig-zag copper foil tape is on both sides of the transparency, you get a full 20′ length of accordioned copper on each end! Here’s the whole antenna strung across the width of my basement ham shack:

…and then a 15′ twin-lead feedline is run from the centerpoint and plugged into a balun on an antenna tuner (whose job is to automatically match impedance between radio and antenna for a given transmission frequency.)

Yes, of course, it’s insane to do a first test drive in the basement, but I was too lazy to string the thing outside my window late at night. This antenna will really be strung across hotel rooms, hopefully on as high a floor as possible. But even with crappy basement RF reception, I was still able to immediately hear morse code conversations on 20 and 40 meter bands. And for the first time in my life, I was able to hear conversations on 80 meters as well! (My current outdoor antenna only does 20 and 40 meter.) This was also my first experience with an antenna tuner, and I was amazed to watch it ker-chunk and auto-tune whenever I transmitted 5 watts on different frequencies. Nobody was able to hear my transmissions, but hey, it was in a basement. And the thing didn’t smoke or catch on fire. 🙂

Ham Radio: now with Morse Code

Posted by on Sunday, 18 July, 2010

OK, I got my level 2 (General) license. I’ve got the 50′ wire going across the backyard, from top of my house to a tree, and I’ve chatted with folks from my ham shack^H^H^H basement now — several eastern seaboard states, and last night even someone in SF. But hey, the ionosphere is kinda random. Lots of noise and static. And yet somehow, those morse code conversations I’m hearing seem to cut right through the static.

So even though it’s no longer a requirement, I’ve started learning morse code for fun. Yes, for fun. My mentors tell me it will allow me to make longer-distance contacts through even the worst environmental conditions. And even cooler: you can build pocket-sized tranceiver kits that send and receive morse. Just throw a wire out your hotel window, plug it into your altoids tin, and soon you’re chatting with folks in Australia. Okay, you may still be chatting in binary, but it’s still chatting. 🙂 So I’m busy listening to some tapes that teach me one letter at a time, slowly building up my vocabulary. It’s slow going, but amusing and satisfying in the same way learning to arpeggiate a banjo once was.

What’s also fascinating is all the ergonomic research that has gone into devices for sending morse. It’s like the whole qwerty/dvorak/maltron insanity all over again! While most people are told to start out with simple telegraph keys, it seems that what’s ubiquitous are these things called ‘paddles’. It’s two little levers that you push toward each other — one with your thumb, one with your index finger — and it’s hooked up to an electronic tone generator. One paddle makes a continuous series of ‘dits’ when you push it, and the other makes a continuous series of ‘dahs’. So you get the sounds by wiggling your two fingers back and forth, sometimes holding levers longer, sometimes not. You can adjust the speed of the auto-repeat as well, depending on how fast you want to go. Here’s a video that shows an expert in action:

Ham Radio: Satisfaction at Last

Posted by on Saturday, 3 July, 2010

So it turns out I couldn’t hear anything on my backyard horizontal-wire antenna because I had it hooked up to a handheld walkie-talkie tranceiver. In brief: those things can’t decode the sidebands used on the low frequencies, and have horrible sensitivity and selectivity. As soon as I hooked up a “real” HF tranceiver (my new ICOM IC-7200), I could hear people chatting on all sorts of long wavelengths. Amazing!

At this point, I took a business trip to Atlanta with my handie-talkie in my bag. From the 20th floor of my midtown hotel I finally was able to make my very first contact to a local area ham over 2 meter FM. He welcomed me to the hobby and we blabbed for a while. The next night I participated in an Atlanta area multi-way chat session over a repeater. My enthusiasm only increased after this.

Back at home in Chicago, I finally made my first couple of contacts over the 20 meter band: first to St. Louis, then to central Ohio. And tonight, I’ve made contacts with New York, Maryland, and Massachusetts as part of a special 4th of July weekend “event” — a game in which you try to contact specially planted operators in each of the 13 colonies. If you reach all 13, you get a special certificate. I thought this was silly at first, but after reaching three, I started getting eager to hunt down the fourth! Maybe these contests are more addictive than I expected…

I finally made contact with some local hams as well, using a Chicago-area repeater on top of the Standard Oil building downtown. They were quite welcoming, asking me to meet them at their monthly meeting or every-Saturday brunch at a local diner. I think it’ll be great to get some direct support from people nearby, rather than pestering my mentor over email all the time!

I wonder if anyone has ever actually written an ethnography of amateur radio culture. (Clare, do you know?) It’s been a fascinating jump into the deep-end of a very specific set of rituals, jargon, and history. Some initial observations I’ve made:

  • 90% of those participating are retired men. Much like my love of banjo and barbershop quartets, I seem to have yet again confirmed that I am an old guy at heart.
  • The country seems populated with tons of amateurs like me with “small” transmission power (between 5 and 25 watts), and a few diehards with “big” transmission power (anywhere from 500 to 1200 watts). When scanning the bands, the typical scenario shows up over and over: some big-gun is asking for contacts, and dozens of small fish are screaming all at once to be recognized, hoping they’re heard in the crowd. The big gun chooses a lucky minnow, they exchange callsigns and say hello, log each other, and then the crowd starts screaming again. It’s like the big gun is the pretty girl at the party — everyone gathers around and wants to chat with her. Perhaps this is why hams quest to build ever more powerful antennas in their backyards; more transmission power creates more popularity!
  • Because the communication mode is simplex (you can’t transmit and receive at the same time, like you can on a telephone), people have a very special set of rituals for “passing the microphone” back and forth. For two people chatting, it’s the usual junk you hear truckers say on CB radio: they end their statements with “over” or “back to you”. But in 3 or 5 way chat, people pass control around in a very polite circle. When people get the floor, they tend to ramble and pontificate for at least 2 minutes before passing it on. The conversation ends up sounding more like a set of parliamentary speeches, rather than guys sitting around at a bar.
  • That’s the news from the field for now. More to come.

Ham Radio: the saga continues

Posted by on Sunday, 6 June, 2010

In part one of the story I talked about how I got hooked on amateur radio overnight, crammed some textbooks for two weeks, and passed my Technician and General exams. With a newly-issued FCC callsign in hand, it was a bright future ahead!

Well, two weeks later, and I’ve still not made a single successful contact with anyone. It’s been frustrating. I started out ordering a small handheld walkie-talkie radio (“HT” is the lingo). Hams use these for VHF/UHF socializing within a radius of a dozen miles or so. For three nights I listened to hams chatting around the Chicago area, but whenever I tried to transmit and say hello, they couldn’t hear me. At one point someone thought they could hear me and asked me turn “turn up the power”, but I was already at the 5 watts maximum. Then the INTERNET told me that the standard rubber-duck antennas that ship with these tiny radios can’t hit the side of a barn. No problem. I order a much nicer, longer antenna with rave reviews. But nothing gets any better — I still can’t hit a repeater 4 miles away on the top of a Chicago skyscraper in the heart of downtown. What gives? Do I need to build myself a handheld directional antenna, like a mini-dish I can aim eastward?

Meanwhile, my mentor (or ‘elmer’ as hams call it) popped in to visit today from Virginia. He brought with him a special 40-foot long wire which works as an antenna on the low-frequency, long-wavelength radio bands. These are the wavelengths which travel hundreds (or even thousands) of miles by bouncing around off the ionosphere. All you have to do is string the wire across the backyard about 30′ up, and then run a coax cable into the tip of it. The other end of the coax cable goes into your radio. Well, my buddy wasn’t kidding about how you “always remember an antenna hang”. It was like doing a barn raising! It took us all afternoon.

We started by going into the alley and tying a heavy weight (in this case, a dead wall wart) to a piece of string. Wife and wee boys all gathered round to watch.

From antenna hang

Of course, we had the official Antenna Book from ARRL, a worthy tome to give us luck.

From antenna hang

With great dexterity, my friend flung the rope into the tree, but missed a couple of times.

From antenna hang
From antenna hang

Eventually I gave the throw a shot and managed to get it exactly through the right spot in the tree on the second try. Then we had to reel up the official tie-line.

From antenna hang

Next, we took 120 feet of RG-8X coaxial cable and pushed half of it through a hole in our basement window. The hole was conveniently left there after I asked AT&T to come over last week and remove our completely unused land lines. We could even reuse the braces going alongside the house and upwards! Of course what I’m not showing here is the hour of soldering PL-259 connectors to each end of the cable. 🙂

From antenna hang
From antenna hang

Once the cable reached the window of my son’s bedroom, I was ready to drill an eyelet outside the window as a ‘launch point’ for the antenna, and plug the coax feed line into it. I’m sure my wife didn’t mind me drilling into the house at all.

From antenna hang

…and then screwing in a hook…

From antenna hang

In the end, the antenna was pulled up to the hook and now looks like this from the back porch.

From antenna hang

…which is actually much less conspicuous than the power line. In fact, if you stand on the porch and look across the backyard, you can’t even see the antenna line.

From antenna hang

In that picture above, the line on the left is the power line. The antenna line on the right goes through the tree and is just too thin to see!

And now for the second disappointment. After that whole afternoon, we went down to the basement and plugged our walkie-talkies into the new super antenna and tried to listen to the low frequencies. Nothing! That’s right, instead of hearing people talking, we heard nothing but static and reflected images of overpowered AM stations. Now Chicago is definitely overcrowded, RF-wise. But something is definitely weird and wrong. Neither of our radios could hear anything, and even after dark (when the ionosphere works better for bouncing long wavelengths) things only barely improved. We have no idea what’s wrong, so I may invite another ham over with Big Desktop Ham Radio to see if things are really messed up somewhere, or if the handheld radios are just too awful to isolate signal from noise.

One thing is certain: this hobby is going to take a lot of patience.

Studying Ham

Posted by on Sunday, 9 May, 2010

My dad used to be into scanning police conversations, and I recently found his old top-of-the-line 1994 scanner in an old box in our basement. I spent a weekend trying to fix it — taking it apart, trying to replace parts, etc. I eventually gave up in frustration, but before running out to buy a new scanner my wife suggested I ask to borrow one from a co-worker first.

So I did. I put out an email to all the engineers in my office, and one of them lent me a nifty handie-talkie (a Yaesu VX-3R) and a giant instruction manual. Sure enough, I was able to scan, but was curious about the “PTT” button he told me not to push. Next thing I know I’m listening to net meetings over local repeaters! A few days later, I find myself reading the ARRL Technician textbook, and thinking “hey, this is basic high school physics!” Not so hard at all.

I’ll be taking the Technician exam in a week or two, so I can buy my own HT. But my goal is to (probably) upgrade to General and put up an antenna somewhere, so I can use HF to chat with specific friends across the country who I only (just this week!) discovered were licensed hams.

It’s sort of incredible — ham culture is like this ancient geeky brotherhood that secretly infiltrates all other nerdy hobbies. I’m discovering swaths of friends and acquaintances (gaming friends, Google co-workers, open source people) who all have callsigns, sort of a secret handshake. And reading about the culture in the exam textbook is fascinating — someone ought to write an ethnography of this group!