Weather maps sent via shortwave radio. Started in the 1950s and still running today, available by FTP on the NOAA site.
Every FM Radio Station Rendering
A “Paeansonic” radio from eBay – a paean is a “song or lyric poem expressing triumph or thanksgiving“. A pretty great way to beat copyright and suggest the poetic qualities of your FM radio.
SDR/HackRF One: Mac Setup and Basics
The HackRF One is a very nice software-defined radio (SDR). Though a good bit more expensive than other SDR hardware, it is very well made and Michael Ossmann of Great Scott Gadgets has put together an extensive set of free video tutorials. Of course, those only help if you have everything set up correctly to begin with.
It appears that most SDR work is done through Linux, which makes sense: SDR is classic hardware/software hacking. But for a Mac user, I found it somewhat difficult to get started. This short tutorial will hopefully help kickstart that process for you!
Weather Fax Over Ham Radio
A weather report “fax” sent by ham radio (more examples and details here).
Racal MA-4204 Time Division Voice Scrambler
Another device using random acoustic noise for cryptographic purposes. This device from the early 1970s randomly rearranges the audio signal every half-second; a corresponding unit puts the audio back in the correct order on the other end. While not very secure (the three 8-position switches only provide 512 possible combinations), this device’s operation and style have a nice mix of of functionality and poetics.
Via Cryptography Museum.
A Few Historical Random Number Generators
A few historical random number generators. From top to bottom: Galton’s dice (capable of 24 digits instead of the usual 6), a Type 1390-B Random Noise Generator (runs on 6D4 tubes and was likely the device used for RAND Corp’s “A Million Random Digits”), and the first two iterations of random.org’s generators (both run on un-tuned radio noise fed into a computer).
“Japanese Slot Machine”
The weirdly musical signal from the “Japanese Slot Machine” station, thought to be broadcasting from the Japanese Navy. Via this very comprehensive list.
Crystal radio, built into a corn-cob pipe – from Popular Science, volume 101, #3 (Sept 1922).
Every Possible Radio Callsign
KAAA, KAAB, KAAC, KAAD, KAAE, KAAF, KAAG, KAAH, KAAI, KAAJ, KAAK, KAAL, KAAM, KAAN, KAAO, KAAP, KAAQ, KAAR, KAAS, KAAT, KAAU, KAAV, KAAW, KAAX, KAAY, KAAZ, KABA, KABB, KABC, KABD, KABE, KABF, KABG, KABH, KABI, KABJ, KABK, KABL, KABM, KABN, KABO, KABP, KABQ, KABR, KABS, KABT, KABU, KABV, KABW, KABX, KABY, KABZ, KACA, KACB, KACC, KACD, KACE, KACF, KACG, KACH, KACI, KACJ, KACK, KACL, KACM, KACN, KACO, KACP, KACQ, KACR, KACS, KACT, KACU, KACV, KACW, KACX, KACY, KACZ, KADA, KADB, KADC, KADD, KADE, KADF, KADG, KADH, KADI, KADJ, KADK, KADL, KADM, KADN, KADO, KADP, KADQ, KADR, KADS, KADT, KADU, KADV, KADW, KADX, KADY, KADZ, KAEA, KAEB, KAEC, KAED, KAEE, KAEF, KAEG, KAEH, KAEI, KAEJ, KAEK...
Thinking about which callsign to unnoficially assign ourselves for the microbroadcasting project at Drift Station, I thought “how many possible combinations of the four-letter callsign can there be?” The answer is 17,576 for both east (prefix of W) and west (prefix of K) of the Mississippi; the list was generated using TextMechanic.com’s great tools.
[ download the entire list as a .csv file here or as a text file (can be viewed in your browser) ]