The Elliot 152 was a
vacuum tube
A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...
fixed-program computer developed for naval gunnery control at the
Elliott Brothers laboratory in
Borehamwood, Hertfordshire. It was an early example of a digital
real-time computer system, and the first computer produced by Elliott Brothers. The first and only unit was made operational in 1950.
The machine used 16-bit words and
two's complement binary arithmetic. Instruction words were 20 bits long. Read/write memory was provided by a bank of 16
Williams tubes, a cathode-ray tube that could store 256 bits of data – the total memory was 256 16-bit words. The access time of the memory limited the processor clock speed to 333 kHz. The computer could multiply two numbers in 60 microseconds.
[Simon Lavington, ''Moving Targets: Elliott-Automation and the Dawn of the Computer Age in Britain, 1947 – 67'', Springer Science & Business Media, 2011, pp. 58-62] The system hardware was built on glass
printed circuit board
A printed circuit board (PCB), also called printed wiring board (PWB), is a Lamination, laminated sandwich structure of electrical conduction, conductive and Insulator (electricity), insulating layers, each with a pattern of traces, planes ...
modules, but these proved to be unreliable. Intended as the centrepiece of the MRS5 fire control system, instead the
Admiralty proceeded with an alternative design based on analog electronics. However, experience with the 152 was valuable to Elliott Brothers in the development of their other models of computer.
See also
*
List of vacuum-tube computers
References
Vacuum tube computers
Naval guns of the United Kingdom
Early British computers
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