One of the things I like about ham radio is that there’s something for everyone. You can go for contesting, where the real pros will be be working 300+ stations an hour, working on contacting every region in the contest for maximum points. You can sit around and chat with your friends across the country for hours on end. You can interface your radio with a computer and use one of several digital technologies (an area with lots of innovation.) You can work through satellites. You can transmit images.
But there are some neat ones out there. The lowest-frequency ‘official’ ham band is 160 Meters, or 1800-2000 kHz. (Slightly above the AM broadcast band.) But it turns out there’s a 1750 Meter band, down around 175 kHz (0.175 MHz). It’s an unlicensed band, and is classified as “Very Low Frequency.” (VLF aficionados are often termed lowfers.) For the heck of it, I tuned down there (I wasn’t really sure if I could tune that low, actually). All I got was lots of localized noise, but it turns out that there’s a hobby called NBD DXing, or hunting down far-away beacon stations. (This isn’t strictly ham radio as much as a radio-listening hobby outside the ham bands, but still…)
Here’s a fun one: QRSS. It’s basically very low-speed Morse code, but part of the appeal is that it takes only a couple Hertz bandwidth. (Voice signals tend to take in the neighborhood 20 kHz, or 20,000 Hz, of bandwidth.) This also allows for very fine-tuned filters, permitting the signal to be picked out of very strong interference. The concept is really pretty bizarre, I have to admit.
Based on that work, someone developed DFCW. It’s a twist on Morse code where, rather than having dits (short / “dots”) and dahs (long / “dashes”), you have one length (dits), but you use two different tones, speeding up transmission. (Of course, “speeding up” refers to speeding up something described as extreme slowspeed, so it’s still slow.) It’d be interesting to see if this ever becomes used in lieu of ‘normal’ Morse code.
And then there’s Jason, a “keyboard-to-keyboard” digital mode which is designed to use under 5Hz bandwidth. Like the other bizarre slow-speed modes, this one is predominantly used on VLF.
So after taking the radio down practically as low as it would go, I started turning around the VHF frequencies, where more common, local FM communications take place. Even though we have some great lists of repeaters, it’s fun to just tune around the band sometimes. I stumbled across a repeater I never knew existed, where I caught the end of a QSO about fire towers. Much like some of the other stuff I’ve mentioned, it’s not strictly ham-related, but it was pretty interesting. There are apparently still a bunch used in Massachusetts. Mixing what I heard and what I found on Wikipedia, it’s actually pretty interesting. They usually cover huge areas (hundreds of square miles), watching for fires during the ‘fire seasons.’ When they observe smoke, they’ll obtain a bearing and can approximate distance. But the way they’re really meant to work is that a couple different fire towers will observe the same thing, and they can triangulate, with pretty good accuracy, the exact location, and have the fire crew dispatched. I thought they were a thing of the past. If they’re not busy, they’ll often welcome visitors; some even keep a guestbook.
Oh, and software-defined radio is an emerging trend in ham radio, too.
I’ve got to upgrade my license!