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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 ...
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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 ...
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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 ...
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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 ...
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Borehamwood
Borehamwood (, historically also Boreham Wood) is a town in southern Hertfordshire, England, from Charing Cross. Borehamwood has a population of 31,074, and is within the London commuter belt. The town's film and TV studios are commonly known as Elstree Studios. History One of the earliest mentions of Bosci de Boreham (Wood of Boreham), is in 1188: :"In 1188 Pope Clement granted to the kitchen of the monastery the whole land of Elstree. He also gave to the Abbey the wood of Boreham for the feeding of the swine." In 1776, the House of Lords granted: :"An Act for dividing and closing the Common or Waste Ground, called Boreham Wood Common, in the Parish of Elstree otherwise Idletree, in the County of Hertford." Borehamwood was historically part of the parish of Elstree. A separate ecclesiastical parish of "All Saints, Boreham Wood" was created on 26 February 1909, covering the part of Elstree parish east of the Midland Railway. Despite this change to the ecclesiastical boundari ...
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Real-time Computing
Real-time computing (RTC) is the computer science term for hardware and software systems subject to a "real-time constraint", for example from event to system response. Real-time programs must guarantee response within specified time constraints, often referred to as "deadlines". Ben-Ari, Mordechai; "Principles of Concurrent and Distributed Programming", ch. 16, Prentice Hall, 1990, , page 164 Real-time responses are often understood to be in the order of milliseconds, and sometimes microseconds. A system not specified as operating in real time cannot usually ''guarantee'' a response within any timeframe, although ''typical'' or ''expected'' response times may be given. Real-time processing ''fails'' if not completed within a specified deadline relative to an event; deadlines must always be met, regardless of system load. A real-time system has been described as one which "controls an environment by receiving data, processing them, and returning the results sufficiently quic ...
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Two's Complement
Two's complement is a mathematical operation to reversibly convert a positive binary number into a negative binary number with equivalent (but negative) value, using the binary digit with the greatest place value (the leftmost bit in big- endian numbers, rightmost bit in little-endian numbers) to indicate whether the binary number is positive or negative (the sign). It is used in computer science as the most common method of representing signed (positive, negative, and zero) integers on computers, and more generally, fixed point binary values. When the most significant bit is a one, the number is signed as negative. . Two's complement is executed by 1) inverting (i.e. flipping) all bits, then 2) adding a place value of 1 to the inverted number. For example, say the number −6 is of interest. +6 in binary is 0110 (the leftmost most significant bit is needed for the sign; positive 6 is not 110 because it would be interpreted as -2). Step one is to flip all bits, yielding 1001. St ...
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Printed Circuit Board
A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in Electrical engineering, electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a Lamination, laminated sandwich structure of conductive and insulating layers: each of the conductive layers is designed with an artwork pattern of traces, planes and other features (similar to wires on a flat surface) Chemical milling, etched from one or more sheet layers of copper Lamination, laminated onto and/or between sheet layers of a Insulator (electricity), non-conductive substrate. Electrical components may be fixed to conductive pads on the outer layers in the shape designed to accept the component's terminals, generally by means of soldering, to both electrically connect and mechanically fasten them to it. Another manufacturing process adds Via (electronics), vias: plated-through holes that allow interconnections between layers. ...
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British Admiralty
The Admiralty was a department of the Government of the United Kingdom responsible for the command of the Royal Navy until 1964, historically under its titular head, the Lord High Admiral – one of the Great Officers of State. For much of its history, from the early 18th century until its abolition, the role of the Lord High Admiral was almost invariably put "in commission" and exercised by the Lords Commissioner of the Admiralty, who sat on the governing Board of Admiralty, rather than by a single person. The Admiralty was replaced by the Admiralty Board in 1964, as part of the reforms that created the Ministry of Defence and its Navy Department (later Navy Command). Before the Acts of Union 1707, the Office of the Admiralty and Marine Affairs administered the Royal Navy of the Kingdom of England, which merged with the Royal Scots Navy and the absorbed the responsibilities of the Lord High Admiral of the Kingdom of Scotland with the unification of the Kingdom of Great ...
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List Of Vacuum Tube Computers
Vacuum-tube computers, now called first-generation computers, are programmable digital computers using vacuum-tube logic circuitry. They were preceded by systems using electromechanical relays and followed by systems built from discrete transistors. Some later computers on the list had both vacuum tubes and transistors. This list of vacuum-tube computers is sorted by date put into service: }) are identical, except input-output equipment. Both were used internally. , - , The Wegematic 1000 , , 1960 , , , Improved version of the ALWAC III-E , - , ZRA 1 , , 1960 , , , Built by VEB Carl Zeiss, Jena, German Democratic RepublicSiegmar Gerber: ''Einsatz von Zeiss-Rechnern für Forschung, Lehre und Dienstleistung in Informatik in der DDR – eine Bilanz''. GI-Edition, Bonn 2006, p. 310–318 , - , Minsk-1 , , 1960 , , , Built in Minsk , - , Odra 1001 , , 1960 , , , First computer built by Elwro, Wroclaw, Poland , - , Minsk-1 , , 1960 , , , Built in Minsk , - ...
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Vacuum Tube Computers
Vacuum-tube computers, now called first-generation computers, are programmable digital computers using vacuum-tube logic circuitry. They were preceded by systems using electromechanical relays and followed by systems built from discrete transistors. Some later computers on the list had both vacuum tubes and transistors. This list of vacuum-tube computers is sorted by date put into service: }) are identical, except input-output equipment. Both were used internally. , - , The Wegematic 1000 , , 1960 , , , Improved version of the ALWAC III-E , - , ZRA 1 , , 1960 , , , Built by VEB Carl Zeiss, Jena, German Democratic RepublicSiegmar Gerber: ''Einsatz von Zeiss-Rechnern für Forschung, Lehre und Dienstleistung in Informatik in der DDR – eine Bilanz''. GI-Edition, Bonn 2006, p. 310–318 , - , Minsk-1 , , 1960 , , , Built in Minsk , - , Odra 1001 , , 1960 , , , First computer built by Elwro, Wroclaw, Poland , - , Minsk-1 , , 1960 , , , Built in Minsk , - ...
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Naval Guns Of The United Kingdom
A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval warfare, naval and amphibious warfare; namely, lake-borne, riverine, littoral zone, littoral, or ocean-borne combat operations and related functions. It includes anything conducted by surface Naval ship, ships, amphibious warfare, amphibious ships, submarines, and seaborne naval aviation, aviation, as well as ancillary support, communications, training, and other fields. The strategic offensive role of a navy is Power projection, projection of force into areas beyond a country's shores (for example, to protect Sea lane, sea-lanes, deter or confront piracy, ferry troops, or attack other navies, ports, or shore installations). The strategic defensive purpose of a navy is to frustrate seaborne projection-of-force by enemies. The strategic task of the navy also may incorporate nuclear deterrence by use of submarine-launched ballistic missiles. Naval operations can be broa ...
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