By 1982 Sinclair Research Limited had established themselves as a major supplier of cheap microcomputers for enthusiasts wanting to experience this new fad. Clive Sinclair began selling cheap consumer electronics during the 1960s and made his name producing Hi-Fi amplifiers, pocket LCD calculators, and the electronic wrist watch.
After his company, Sinclair Radionics, had been sold to the National Enterprise Board Clive began a new company with Chris Curry producing a low cost microcomputer, the MK14, in 1978. By 1979 Chris Curry had left to start Acorn Computers and Sinclair began work on the ZX80 computer.
Both the ZX80 and the ZX81 were incredibly popular mail order computers that are credited with launching the home computer revolution in the UK. These two micro’s were very cheap at £49.95 and based around the same Zilog Z80 microprocessor and 1kb RAM.
By 1982 the press was eager to find out what Sinclair Research were doing next. Much speculation was around a machine known as the ZX82 and a colour version of the then popular ZX81 with 16kb RAM pack. The Spectrum project was based on the ZX80/81 systems but enhanced to include colour graphics and sound in order to meet the requirements for the BBC’s Computer Programme initiative.
The Spectrum arrived late and the BBC choose to go with a rival design by Chris Curry’s Acorn, their Atom successor the Proton (released as the BBC Micro). The Spectrum was finally announced in May 1982 with mail order adverts appearing in computer magazines around June/July time.
Sinclair promised a 28 day lead but were infamously poor at keeping to manufacturing targets. While a handful of users may have got early models by August 1982, many were still complaining as late as October that their orders still hadn’t been fulfilled. It finally went on full retail sale in stores like WH Smith in January 1983.