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TRADIC
The TRADIC (for TRAnsistor DIgital Computer or TRansistorized Airborne DIgital Computer) was the first transistorized computer in the USA, completed in 1954. The computer was built by Jean Howard Felker of Bell Labs for the United States Air Force while L.C. Brown ("Charlie Brown") was a lead engineer on the project, which started in 1951. The project initially examined the feasibility of constructing a transistorized airborne digital computer. A second application was a transistorized digital computer to be used in a Navy track-while-scan shipboard radar system. Several models were completed: TRADIC Phase One computer, Flyable TRADIC, Leprechaun (using germanium alloy junction transistors in 1956) and XMH-3 TRADIC. TRADIC Phase One was developed to explore the feasibility, in the laboratory, of using transistors in a digital computer that could be used to solve aircraft bombing and navigation problems. Flyable TRADIC was used to establish the feasibility of using an airborne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transistor Computer
A transistor computer, now often called a second-generation computer, is a computer which uses discrete transistors instead of vacuum tubes. The first generation of electronic computers used vacuum tubes, which generated large amounts of heat, were bulky and unreliable. A second-generation computer, through the late 1950s and 1960s featured circuit boards filled with individual transistors and magnetic core memory. These machines remained the mainstream design into the late 1960s, when integrated circuits started appearing and led to the third-generation computer. History The University of Manchester's experimental Transistor Computer was first operational in November 1953 and it is widely believed to be the first transistor computer to come into operation anywhere in the world. There were two versions of the Transistor Computer, the prototype, operational in 1953, and the full-size version, commissioned in April 1955. The 1953 machine had 92 point-contact transistors and 550 di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harwell CADET
The Harwell CADET was the first fully transistorised computer in Europe, and may have been the first fully transistorised computer in the world. The electronics division of the Atomic Energy Research Establishment at Harwell, UK built the Harwell Dekatron Computer in 1951, which was an automatic calculator where the decimal arithmetic and memory were electronic, although other functions were performed by relays. By 1953, it was evident that this did not meet AERE's computing needs, and AERE director Sir John Cockcroft encouraged them to design and build a computer using transistors throughout. E. H. Cooke-Yarborough based the design around a 64-kilobyte (65,536 bytes) magnetic drum memory store with multiple moving heads that had been designed at the National Physical Laboratory, UK. By 1953 his team had transistor circuits operating to read and write on a smaller magnetic drum from the Royal Radar Establishment. The machine used a low clock speed of only 58 kHz to avo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mailüfterl
Mailüfterl is a nickname for the Austrian ''Binär dezimaler Volltransistor-Rechenautomat'' (binary-decimal fully transistorized computing automaton), an early transistorized computer. Other early transistorized computers included TRADIC, Harwell CADET and TX-0. Mailüfterl was built from May 1956 to May 1958 at the Vienna University of Technology by Heinz Zemanek. Heinz Zemanek had come to an agreement with Konrad Zuse, whose company Zuse KG would finance the work of Rudolf Bodo, who helped build the Mailüfterl, also that all circuit diagrams of the Z22 were supplied to Bodo and Zemanek, and that after the Mailüfterl project Bodo should work for the Zuse KG to help build the transistorized Z23. The first program, computation of the prime 5,073,548,261, was executed in May 1958. Completion of the software continued until 1961. The nickname was coined by Zemanek: ''Even if it cannot match the rapid calculation speed of American models called "Whirlwind" or "Typhoon", it w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Labs
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by multinational company Nokia. With headquarters located in Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. Researchers working at Bell Laboratories are credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device (CCD), information theory, the Unix operating system, and the programming languages B, C, C++, S, SNOBOL, AWK, AMPL, and others. Nine Nobel Prizes have been awarded for work completed at Bell Laboratories. Bell Labs had its origin in the complex corporate organization of the Bell System telephone conglomerate. In the late 19th century, the laboratory began as the Western Electric Engineering Department, l ... [...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] |
B-52 Stratofortress
The Boeing B-52 Stratofortress is an American long-range, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing, which has continued to provide support and upgrades. It has been operated by the United States Air Force (USAF) since the 1950s. The bomber is capable of carrying up to 70,000 pounds (32,000 kg) of weapons,"Fact Sheet: B-52 Superfortress." ''Minot Air Force Base'', United States Air Force, October 2005. Retrieved: 12 January 2009. and has a typical combat range of around 8,800 miles (14,080 km) without aerial refueling. Beginning with the successful contract bid in June 1946, the B-52 design evolved from a < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diode
A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other. A diode vacuum tube or thermionic diode is a vacuum tube with two electrodes, a heated cathode and a plate, in which electrons can flow in only one direction, from cathode to plate. A semiconductor diode, the most commonly used type today, is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals. Semiconductor diodes were the first semiconductor electronic devices. The discovery of asymmetric electrical conduction across the contact between a crystalline mineral and a metal was made by German physicist Ferdinand Braun in 1874. Today, most diodes are made of silicon, but other semiconducting materials such as gallium arsenide and germanium are also used. Among many uses, diodes are found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manchester Computers
The Manchester computers were an innovative series of Von Neumann architecture, stored-program Computer, electronic computers developed during the 30-year period between 1947 and 1977 by a small team at the Victoria University of Manchester, University of Manchester, under the leadership of Tom Kilburn. They included the world's first stored-program computer, the world's first transistorised computer, and what was the world's fastest computer at the time of its inauguration in 1962. The project began with two aims: to prove the practicality of the Williams tube, an early form of computer storage, computer memory based on standard cathode-ray tubes (CRTs); and to construct a machine that could be used to investigate how computers might be able to assist in the solution of mathematical problems. The first of the series, the Manchester Baby, ran its first program on 21 June 1948. As the world's first stored-program computer, the Baby, and the Manchester Mark 1 developed from it, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct-coupled Transistor Logic
Direct-coupled transistor logic (DCTL) is similar to resistor–transistor logic (RTL) but the input transistor bases are connected directly to the collector outputs without any base resistors. Consequently, DCTL gates have fewer components, are more economical, and are simpler to fabricate onto integrated circuits than RTL gates. Unfortunately, DCTL has much smaller signal levels, has more susceptibility to ground noise, and requires matched transistor characteristics. The transistors are also heavily overdriven; that is a good feature in that it reduces the saturation voltage of the output transistors, but it also slows the circuit down due to a high stored charge in the base. Gate fan-out is limited due to "current hogging": if the transistor base-emitter voltages () are not well matched, then the base-emitter junction of one transistor may conduct most of the input drive current at such a low base-emitter voltage that other input transistors fail to turn on. DCTL is close to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leprechaun DCTL
A leprechaun ( ga, leipreachán/luchorpán) is a diminutive supernatural being in Irish folklore, classed by some as a type of solitary fairy. They are usually depicted as little bearded men, wearing a coat and hat, who partake in mischief. In later times, they have been depicted as shoe-makers who have a hidden pot of gold at the end of the rainbow. Leprechaun-like creatures rarely appear in Irish mythology and only became prominent in later folklore. Etymology The Anglo-Irish (Hiberno-English) word ''leprechaun'' is descended from Old Irish ''luchorpán or lupracán'', via various (Middle Irish) forms such as ''luchrapán, lupraccán'', (or var. ''luchrupán''). Modern forms The current spelling is used throughout Ireland, but there are numerous regional variants. John O'Donovan's supplement to O'Reilly's ''Irish-English Dictionary'' defines as "a sprite, a pigmy; a fairy of a diminutive size, who always carries a purse containing a shilling".O'Donovan in O'Reilly (18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junction Transistor
A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor, uses only one kind of charge carrier. A bipolar transistor allows a small current injected at one of its terminals to control a much larger current flowing between the terminals, making the device capable of amplification or switching. BJTs use two p–n junctions between two semiconductor types, n-type and p-type, which are regions in a single crystal of material. The junctions can be made in several different ways, such as changing the doping of the semiconductor material as it is grown, by depositing metal pellets to form alloy junctions, or by such methods as diffusion of n-type and p-type doping substances into the crystal. The superior predictability and performance of junction transistors quickly displaced the original point-contact transistor. Diffused transistors, along wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineer
Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the limitations imposed by practicality, regulation, safety and cost. "Science is knowledge based on our observed facts and tested truths arranged in an orderly system that can be validated and communicated to other people. Engineering is the creative application of scientific principles used to plan, build, direct, guide, manage, or work on systems to maintain and improve our daily lives." The word ''engineer'' (Latin ) is derived from the Latin words ("to contrive, devise") and ("cleverness"). The foundational qualifications of an engineer typically include a four-year bachelor's degree in an engineering discipline, or in some jurisdictions, a master's degree in an engineering discipline plus four to six years of peer-reviewed professiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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