Formerly u/CanadaPlus101 on Reddit.

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Joined 1 year ago
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Cake day: June 12th, 2023

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  • Disclaimer that I’m still a noob, too.

    I gave my main recommendation there, for transceiver. I haven’t done the research to have a model or brand in mind, but a cheap SSB (single side-band) radio seems like it should exist, given that you can make such a device with just 7 transistors. Any remotely modern computer will be able to generate an audio signal that, when mixed up to RF the way a SSB radio does, will look like the mode of your choice. Software-wise, I’ve really liked working with GnuRadio so far.

    Amps go for a lot more new, because they have to handle both radio frequencies and >100W powers, and do so without causing distortion. Ham radio is a dying art, so poking around for ones at estate sales or similar seems promising. 100W is generally the recommended minimum if you don’t want to be frustrated.

    For the feedline, assuming you’re doing coax, the design tension is between bendability and DB/meter attenuation. For radio 50 ohm impedance is standard, not 75, so you can’t reuse stuff from cable TV without transformers. (Impedance matching is very important, as you’ll learn getting a licence)

    For the various accessories you may need to connect cables, amps, antenna wires and maybe filters, Amazon. They even have the obscure stuff I’ve needed for my direct sample radio.

    All the prefab antennas I’ve seen seem ludicrously expensive, given that it’s a chunk of ordinary metal, so probably skip that and cut your own. Antenna recipes are all over the place on ham homepages. If you’re doing a bunch of non-resonant antennas, a tuner will save you time, but they cost as much as an amp. Everything that works at the high-power end is expensive.


  • I meant with the pleats, similar to what you see on an actual accordion, or in a bendy straw. It’s how they did the joints on the Apollo space suits, for a vaguely similar application. The shape is sometimes called “bellows”, but that’s pretty confusing when it also refers to an air blowing technology that may or may not involve a diaphragm of any kind.

    If you got enough range of movement with just a straight elastomer cylinder, that works, but if the pressure is pretty modest a variety of stretchy ducts made for HVAC or other home purposes are sold. I have some for draining rainwater, but they seem to break in stiff wind, so YMMV. You could also mold your own again.



  • Yeah, ham radio. If I was doing it all over again, I’d go for the most basic SSB radio I can find that plugs in to a computer sound card - that should in theory be able to do anything reasonable. You’ll also need feed lines, an amp and a large-ish antenna, which is where things get a bit more technical hardware-wise, especially if you’re in an apartment or have something like an HOA, but it nothing you can’t figure out.

    And yes, a licence. So far I’ve found the requirements pretty reasonable in my jurisdiction, they relate to not frying yourself or your equipment, and how not to be a menace to other people sharing the radio bands. You used to need to learn Morse code fluently enough to pass a practical test, but most places have gotten rid of that.