ATV is a cool thing! And, thanks to you, I discovered there's more to it than I remembered from when I last read about it.

The more common form of Amateur TV is SSTV[0] - Slow-scan TV. This runs in 3kHz (!!!) of bandwidth and typically gets transmitted on voice frequencies, since it can fit inside the max occupied bandwidth there. People transmit this on the HF bands, which can go world-wide! But... for FPV-purposes, it's pretty much useless. You're looking at something like 8-114 seconds/frame.

But I had no idea that there's people doing Amateur fast-scan TV[1]. That's pretty cool too! I have no idea how readily available light and portable equipment would be for the 70cm or 33cm bands, but there is a bunch of equipment available for the 23cm (1.2GHz) band. As mentioned in my sibling comment... it's not necessarily legal equipment, and it's kind of just... available... from random distributors in China, but it works OK and you're not all that likely to have someone complain about it in that band, unless you happen to be interfering with their attempts to do the same thing :)

[0] https://en.wikipedia.org/wiki/Slow-scan_television

[1] https://en.wikipedia.org/wiki/Amateur_television

Funny you mentioned SSTV. I'm putting some SSTV software together and have an SSTV contest award hanging on my wall. It's a lot of fun. Fast-scan (what I always think of when I hear ATV) seems pretty extreme to me though. :) Wiki seems to indicate it's used for drone work...or could be...

Huh! I suppose you could do SSTV decoding with a sound card eh? Hmmm, a bit of research suggests there's a 2m SSTV station in town here, although it's not clear if it's still alive. I might have to spend some time fiddling with GNURadio tonight and see what I can whip up.

I kind of want to pull out that cheap Chinese analog FPV camera too and see how disgusting the spectrum on it is. I have pretty low expectations (camera + tx + rx for $20? yeesh...)

73