Recovering old ZX Spectrum tapes, Part 2

Fri, 25 Nov 2016 00:22:31 +0100

The ZX Spectrum was a comparable cheap home computer, and thus the tape loading and saving mechanisms have not been very sophisticated. The tape recording is just a stream of short waves (0 bit) and long waves (1 bit). The stream starts with a leader signal (a series of even longer waves) and a single sync pulse. So, in the theory, reading a tape recording means measuring single wave lengths, by taking the time between two zero-crossings, and converting them into a sequence of bytes.