It should be possible to capture using a sound card.
PCM recorder is probably easiest, and the most like a tape recorder as they're widely used as replacements for dictaphones.
40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
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Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#12I sometimes mention that our radio used to broadcast games you could tape off the air to young people and they fail to grasp the futuristic glory I experienced when I explained to myself it's like one-way modem.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#13I'd like to have a listen to those waves and I'm not in Slovenia, any source on the internet?
Edit: Found a short sample of a Commodore Datasette program on Wikipedia[0].
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#14What I'm most curious about is if this was always just a happy side-effect of cassette-based data storage, or if they put specific effort into making this work. Ie. by being resilient to noise before and after a broadcast, having error correction, etc.
There was no error correction on ZX Spectrum, the protocol was very simple. IIRC a square wave with next bit encoded as timing of next edge, the last byte was XOR of the whole stream serving as error detection.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#15If I remeber correctly BBC also used to do this back in the day.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#16I fondly remember the Pete Shelley album “XL-1” which had a final track that contained a spectrum program.
You dropped the needle on the record and pressed ‘Run’ simultaneously and it would display an animated set of patterns in sync with the music - and the song lyrics
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#17What I'm most curious about is if this was always just a happy side-effect of cassette-based data storage, or if they put specific effort into making this work. Ie. by being resilient to noise before and after a broadcast, having error correction, etc.
There was no error correction on ZX Spectrum, the protocol was very simple. IIRC a square wave with next bit encoded as timing of next edge, the last byte was XOR of the whole stream serving as error detection.
Technical details: https://sinclair.wiki.zxnet.co.uk/wiki/Spectrum_tape_interfa...
Assembly: https://worldofspectrum.net/legacy-info/spectrum-rom-load-ro...
TL;DR:
> A '0' bit is encoded as 2 pulses of 855 T-states each.
> A '1' bit is encoded as 2 pulses of 1710 T-states each (ie. twice the length of a '0')
> A 'pulse' here is either a mark or a space, so 2 pulses makes a complete square wave cycle.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#18If I remeber correctly BBC also used to do this back in the day.
The BBC version was a small square of "static" broadcast in the corner of the closing credits of the Micro Show and you put and square plastic box (you could get from the show, I can't remember if you had to pay for them or not) with a light sensor over that "static" square and run the special software which take the data and save it as a file.
It wasn't terribly reliable but it was an interesting experiment by the BBC.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#19Now could be the right time to put your old tape recorder on eBay (If you are in Slovenia) ;)
You can likely buy a new one on amazon for less than an old one on ebay.
Re: 40 years later, a game for the ZX Spectrum will be again broadcast over FM radio
#20There was a game on Shakin' Stevens' album where you had to hide from bats and open green doors, and even the prawn cracker like snack Skips had a game, colin the biker. Mad times.