The history of the Sinclair ZX Spectrum is one that mirrors the fortunes of the British home computer industry, one of an early 8-bit boom followed by a sharp decline as manufacturers failed to capitalise on the next generation of 16-bit machines. The grey ZX Spectrum on [Keri Szafir]’s bench is one that encapsulates that decline perfectly, being one of the first models produced under the ownership of Amstrad after Sir Clive’s company foundered. Amstrad made many improvements to the Spectrum, but as she demonstrates, there are still some fixes needed.

The machine came her way because of a hum from the tape deck circuitry. The read amplifier was picking up electrical noise, and she fixed it without mods to the circuit but with the simple expedient of powering the analogue circuit from the tape motor switch so it only works when needed.

Beyond that, this machine demonstrates another ’80s innovation, the SCART/Peritel AV connector. These first appeared on early-80s French TV sets, but by the later half of the decade had made it to the UK where Amstrad included support for an adapter cable from the DIN socket on the back of their Spectrum.  Even then they didn’t get it quite right, and she modifies some links on the board to better support it.

Sinclair were famous for on-board bodges, and even in new ownership continued. There’s a reversed transistor and at least one bodged-on component, but of course, it wouldn’t be a Spectrum without bugs, would it!

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