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Elliott 152
The Elliot 152 was a vacuum tube fixed-program computer developed for naval gunnery control at the Elliott Brothers laboratory in Borehamwood, England. 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 modules, but these proved to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliott Brothers (computer Company)
Elliott Brothers (London) Ltd was an early computer company of the 1950s–60s in the United Kingdom. It traced its descent from a firm of instrument makers founded by William Elliott (1780 or 1781-1853) in London around 1804. The research laboratories were originally set up in 1946 at Borehamwood and the first Elliott 152 computer appeared in 1950. In its day the company was very influential. The computer scientist Bobby Hersom was an employee from 1953-1954, and Sir Tony Hoare was an employee there from August 1960 to 1968. He wrote an ALGOL 60 compiler for the Elliott 803. He also worked on an operating system for the new Elliott 503 Mark II computer. The founder of the UK's first software house, Dina St Johnston, had her first programming job there from 1953–1958, and John Lansdown pioneered the use of computers as an aid to planning on an Elliott 803 computer in 1963. In 1966 the company established an integrated circuit design and manufacturing facility in Gle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Williams Tube
The Williams tube, or the Williams–Kilburn tube named after inventors Freddie Williams and Tom Kilburn, is an early form of computer memory. It was the first random-access digital storage device, and was used successfully in several early computers. The Williams tube works by displaying a grid of dots on a cathode-ray tube (CRT). Due to the way CRTs work, this creates a small charge of static electricity over each dot. The charge at the location of each of the dots is read by a thin metal sheet just in front of the display. Since the display faded over time, it was periodically refreshed. It operates faster than earlier acoustic delay-line memory, at the speed of the electrons inside the vacuum tube, rather than at the speed of sound. The system was adversely affected by nearby electrical fields, and required frequent adjustment to remain operational. Williams–Kilburn tubes were used primarily on high-speed computer designs. Williams and Kilburn applied for British patents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, 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. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplifier, amplification and current rectifier, rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
