Clive Sinclair, a U.K. inventor, developed the ZX-80 microcomputer, a small Z-80 based computer that sold for $199 plus $5 shipping. It was advertised in 1980 as the first computer under $200.
The ZX-80 used the Z80A microprocessor chip, came with a touch sensitive membrane keyboard, and could interface with a TV set for showing its 32 character, 24-line display.
The ZX-80 was only 6-1/2 inches wide by 8-1/2 inches long by 1-1/2 inches deep. It came with 4K integer BASIC, a 128 page manual, and a catalog of 27 different program cassettes available.
It was available in the U.S. from Sinclair Research, Ltd., of Wallingford, Connecticut. Sinclair also had offices in Boston, Massachusetts.
Clive Sinclair's next model was the ZX-81, which sold for under $100. Sinclair's English company made an agreement with Timex in the United States, which gave Timex the rights to distribute the ZX-81 in the U.S. under the brand name "Timex-Sinclair."
The Spectrum 128 came with 128 K RAM and utilized the
Zilog Z80A (3.65 Mhz) microprocessor chip.