Radio transmission and reception

Continuing from

Who out there is into HAM and/or shortwave? Apparently music isn’t allowed on HAM frequencies, but I seem to remember it’s pretty common on shortwave? What experiences can you share about either receiption or transmission?

This started out as “it would be cool to sample radio” but @Larrea has me thinking more bidirecitonally now.

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i know nothing about AM, but when it comes to FM radio one can use negligible power transmitters and create interesting things in the area of a performance. Some countries have regulations for uses above µW, and lots of garbage in the FM band, so one might want to choose its frequencies wisely as to not be disrupted by some top40 noise.

You might want to check Tetsuo Kogawa’s work about radio art.
Its “simple transmitter” is cheap and easy to build.

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To clarify a couple things…I hope (I really am no expert!):

Shortwave, strictly speaking, merely refers to a broad specturm of radio frequencies. Within that spectrum, there are narrower bands that are reserved for different services, i.e., governmental, commercial, law enforcement, and, amateur.

Amateur is what we’re primarily interested in.

So the music you are hearing, from say the BBC World Service, Russian service, Voice of America, etc., are operating in a spectrum allocated and agreed upon by most affiliates/signatories (not sure about the formalities) to the International Telecommunication Union, a sort of international NGO that regulates this sort of thing.

In the US, the ARRL is the organization most people go to first for standards and practices, but the actual rules are set and enforced by the FCC, per aforementioned agreements with the ITU.

Ergo, amateurs–me, or any other licensee–are only permitted to broadcast within narrower spectra, and are therefore regulated. Music is prohibited.

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Argh, OK.

Would love to hear more…

Links:

http://www.arrl.org

http://www.itu.int/en/Pages/default.aspx

Here is a useful chart describing the bands available for amateur use:

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don’t overthink it with all these so-called ‘rules’, man! Just blast out the Lincolnshire Poacher sporadically for a few days interspersed with digits of pi or something, see if you can convince the CIA to show up at your house…
EDIT:
disclaimer - please noone actually do this. In my youth I actually did ‘accidentally’ pull a similar kind of prank that actually got taken seriously somehow & nearly went horribly wrong… Why does my brain still insist on thinking of these terrible ideas!?

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More stuff:

Once you pass the first test and get your license, you have, in effect, a radio station. You will get your own call sign, that will sound vaguely like any other radio station–KPCC, WNYU, etc. My only radios are in my Jeep, and a very small handheld mobile that can go anywhere really. So wherever I am is where my station is.

The Tech class license does not permit broadcasting on what is commonly referred to as shortwave, except in CW (morse code) in a couple of very narrow bands. In the radio world, most people refer to SW bands by wavelength: 40 meters, 20 meters, even as long as 160 meters. Weirdly, the “short” in shortwave can be a bit confusing I suppose, as the more commonly used frequencies are not in fact in the shortwave spectrum, but in the VHF and UHF spectra, 6 meters, 2 meters, and 70cm being the most common. There is amateur use above those, but they tend to get more specialized.

All of this said, there is a small degree of unruliness that is present on amateur radio. You quickly figure out which frequencies carry that. Supposedly, there are even some pirate repeaters (radio towers on high points that in effect act as relays for VHF/UHF frequencies, which cannot bounce off the ionosphere like shortwave can; VHF/UHF is line-of-sight) that are tolerated by the FCC; the idea being, it keeps the profanity and insanity contained…but the FCC would never admit to it I imagine.

If you’re doing some sort of sporadic transmissions without a repeater with agreed-upon participants (operating in what’s called simplex, vs. duplex, which involves paired frequencies and repeaters), you should be fine.

Yikes! TMI!

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It’s funny, as I’m bouncing around on the internet reading about stuff, I’m realizing it’s almost trivially easy to commit a felony in this space. Noted!

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I’d like to hear this story!!

Ha - haven’t told this story in ages! School coach trip - one of my friends suggested we write some obsene signs to stick up the back of the bus. I had a better idea & wrote ‘the driver has a gun’, ‘the bus is a bomb’. We chucked the signs up there, probably flipped the bird at some random truck drivers, all had a good laugh, then obviously got bored with it & totally forgot they were up there! Meanwhile some concerned citizen actually rung the authorities to report the bomb scare…

Anyway this was all pre 9/11 everyone was less uptight, there was no SAS raid on the bus and luckily noone got hurt (though armed police were involved, which was kind of a major deal in the UK back then). Bus driver was a bit rattled, as you can imagine! Didn’t get in much trouble, everyone saw the funny side and a couple of teachers trailing the bus in a car had also been chuckling at the signs IIRC. So they couldn’t bollock me too badly. I remember my Dad trying to give me a stern talking to, but he was practically pissing himself laughing.

Anyway yea we live in much more paranoid times now - fooling around on shortwave in the US pretending to be a spy or terrorist would probably be a really bad idea! (oh and I’m guessing most people on this forum are not 14 years old when you can still maybe get away with something that dumb)

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Ha ha ha that’s great!! Man you would get into deep waters doing that now.

well, nowadays one gets arrested for a disassembled clock, so all bets are off.

obligatory link http://websdr.ewi.utwente.nl:8901 , just wait till after dark in Europe. I also like excursions to the more exotic/niche ones in this list http://websdr.org - night/day applies.

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Also been interested in shortwave. I could never find anything when i owned one…I dont know why. Came across this interesting archive of recordings. Im sure there are some great sampling opportunities in there, i’ve even downloaded a few.

There also seems to be quite a few active pirate radio station on shortwave. One of particular interest was a one off Boards of Canada series of broadcasts.

Who knows it could be them… One thing for sure tomorrows harvest drenched in the noisy artifacts of shortwave does suit their musical aesthetic… Well… I like it anyway :slight_smile:

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just have to mention william basinski’s shortwave music, because it fits so well with the ongoing discussion.

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And Aerial 1,2,3

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Not sure if it’s cool to revive such an old topic (and the software is warning me!) but I just read about this documentary called Spectres of Shortwave and got pretty excited:

Synopsis:

A mysterious web of international shortwave radio towers once dominated the Tantramar marshscape. Meanwhile, local residents heard radio broadcasts emanate unexpectedly from their household appliances.

The Radio Canada International shortwave relay site was built during World War 2, to broadcast to Europe and Africa. It continued to broadcast around the world during the Cold War, not only for Canada, but also relaying transmissions for Radio Free Europe. Located in Sackville, New Brunswick, it was perfectly positioned to transmit across the Atlantic Ocean, and covered most of the globe with its transmissions.

This experimental documentary film focuses on the flat marshland landscape accompanied by stories told by local residents and the technicians who worked at the site.

After beginning this project, the Canadian government announced that the Radio Canada International shortwave relay site would be shut down and dismantled. As such, a final chapter was added to the film, which documents the dismantling of this historic structure.

Based on this video and the synopsis, I’d love to watch the whole thing.

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Does any interesting uses of HAM/2 way radio? Has anyone ever incorporated HAM radio into their recordings? How?

Well, you need to consider that it’s illegal to broadcast music (of any kind, not just prerecorded or commercial) over the amateur radio frequencies, so you’d be limited to incorporating reception of other signals. In that sense, it wouldn’t be so different from an RF Nomad module on the shortwave/HF side. On the other hand, many amateur bands are set aside for control frequencies of remote units, so you could conceivably use that feature for some sort of modulation-at-a-distance type thing - but then you’re again not limited to ham bands for that if you stick to public frequencies and low powers. The ham stuff could be useful if you wanted to do some sort of concept where someone several hundred KM away was “playing” music somewhere else, though. Similar thing to some of the internet-based MIDI or OSC protocols.

I’ve been playing around with SDR for a few months. Haven’t done anything in terms of recording yet although I have processed it through my modular.

I bought an SDR dongle from here:
https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/
and am using this free software to receive the signal:
https://airspy.com/download/

Even with a small inside antenna you can get some nice noises and textures. I plan to get a proper outside antenna at some point as I’m really interested in trying to get some VLF recordings.

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