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by nickcw2 hours ago |
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upvoteby BoxOfRain2 hours ago|
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I love learning about pre-internet ways of transferring data on the back of other things. Another cool example is that the UK is only shutting down its longwave AM radio service this month (as opposed to decades ago) because the carrier is phase-modulated with data telling older electric meters to switch over. For years this was the only reason such an antiquated radio system stayed alive.
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upvoteby cf100clunk2 hours ago|
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> I love learning about pre-internet ways of transferring data on the back of other things

See Minitel from France and Telidon from Canada as other examples of data systems riding on analogue TV and/or POTS telephone systems.

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upvoteby mschuster911 hours ago|
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In Munich (Germany), a lot of the displays at bus and tram stations get their data via a side leg on the FM radio broadcast of local station B5 aktuell [1]. More details are here [2], apparently it's called "Axentia iBus FM/DARC".

[1] https://www.mikrocontroller.net/topic/232846

[2] https://apollo.open-resource.org/mission:log:2014:08:08:darc...

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upvoteby reaperducer1 hours ago|
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I love learning about pre-internet ways of transferring data on the back of other things.

I once worked for a radio station that made 90% of its revenue from carrying data feeds on subcarriers, and not from main music programs.

Because of the geographic location and size of the signal, it was a vital link between two major cities before planting fiber optic lines became cheap.

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upvoteby reaperducer1 hours ago|
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They used to rent a single scan line (VBI) of the TV broadcast to use as a data transmission method

In the days before cable TV was widespread, there were over-the-air devices to give you a "TV Guide" page, like your cable/satellite service does now.

It was a tiny gray box about the size of a VHS tape, with a cute antenna sticking out of the top.

It constantly received program listing data through scan line data services, and filtered the listing by your ZIP Code. It displayed its TV Guide page on channel 3 or 4, and passed through the rest of the spectrum from your antenna. Because of this, it could even switch channels for you.

It cost something like $40, and after that was a totally free service, with no advertisements.

I'm pretty sure I got mine at Radio Shack, so it's probably listed in the catalogs around 1994 or so.

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