Interesting article - I do remember the BBC trying this for some of the BBC Micro stuff in the early 80’s via the TVs teletext service but this
is the only article I can find on it right now. It’s not quite the same as cassette tape tones though being (technically) digital end to end.
So, “Telesoftware” - it’s a thing
Neat social history article, but man! am I done with wide-eyed “tHeY uSeD tO sEnD pRoGrAmMeS oVeR rAdIo!!!1!!” articles. BASICODE was a thing for a few years across several countries in Europe, and also the UK. You bought the cassette of conversion routines from the relevant radio station, you recorded the program, decoded it, and with luck you got yet another Hunt the Wumpus clone or Biorhythm calculator to play with.
Programmes lived on tape, so of course transmitting by sound made sense. Disc drives were out of reach due to import duties. We tried sending code over CB radio (failed; got rude responses from the burners around Polo Mint City) and directly over the phone (worked! once, for short BBC micro code at the slowest tape speed - expensive phone call, even locally). Hours of hovering over the tape player, azimuth screwdriver at the ready, honed your hearing to know when a recording was failing.
You can still annoy and amaze (kinda) your housemates by sending data from one computer to another via speakers using minimodem. And then there’s the Chirp! app that sends messages and vCards from phone to phone in the most annoying way possible …
(oh and … hi jhi! We corresponded a couple of decades back when your String::Approx module — plus a whole load of hairy heuristics — helped us at Collins Dictionaries to make a first-cut Catalan-English dictionary framework from Spanish and French sources.)
Wow, it is a small world, I guess.
In the summer of 1984, my friend and I transmitted a program from a ZX81 using an FM wireless bug, to another ZX81 about 100 feet away, which was connected to the earphone socket of an FM radio receiver.
I suppose in principle, though I didn’t try it at the time, that you could run a 3.5mm jack cable between the EAR and MIC sockets of two similar machines.
IIRC, we wrote a short BASIC program, which included the “SAVE” statment at the end of the program followed by a “GOTO nn” on the next line. This put the ZX81 into a continuous SAVE cycle, which gave us multiple cycles to get volume and tuning settings correct.
The receiving ZX81 was left waiting for a LOAD.
BASICODE was one of those good ideas that never really gained popularity. There were so many conflicting dialects of BASIC on the various home machines, some of which tokenised the program to conserve memory, so were not using a standard text file as their cassette interchange format.
There was an active thread on Mastodon seeking captured examples of data sent over-air. Among the findings, this collection of videos from a 5-page thread on TV Forum. Includes a snippet from the radio program Chip Shop: