ZX-80
Sinclair's cheap personal computer with built-in BASIC, launched at the end of January 1980 at a computer fair in Wembley, UK. The processor was an NEC 780-C running at 3.25 MHz. It had 1KB of RAM, externally expandable to 16KB, and 4KB of ROM. It had RF video output to a TV, displaying 24 lines by 32 characters of monochrome text. An audio cassette recorder was used to save programs.
The ZX-80 was sold in kit form for £79.95 or ready-built for £99.95. It was used by many UK hobbyists as a means of learning the basics of computing. Some remember the 1KB ZX-80 for the claim in its advertising that you could control a nuclear power station with it.
The ZX-80 was succeeded by the ZX-81.