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Sutton Tube
Sutton tube was the name given to the first reflex klystron, developed in 1940 by Robert W. Sutton of Signal School group at the Bristol University. The Sutton tube was developed as a local oscillator for the receiver of 10cm microwave radar sets. Due to its geometry and long drift space, it suffered from mode jumping through the tuning range. For this reason, from late 1941 onward, it was replaced in many sets by the Western Electric 707A (also known as McNally tube, named by its developer). The reflex klystron is a type of vacuum tube used to generate microwaves. It is a low-power device used primarily for two purposes: one is to provide a tuneable low-power frequency source for the local oscillators in receiver circuits, and the other, with minor modifications, as a switch that could turn on and off another microwave source. The second use, sometimes known as a soft Sutton tube or rhumbatron switch, was a key component in the development of microwave radar by United Kingdom, B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavity Magnetron
The cavity magnetron is a high-power vacuum tube used in early radar systems and subsequently in microwave ovens and in linear particle accelerators. A cavity magnetron generates microwaves using the interaction of a stream of electrons with a magnetic field, while moving past a series of cavity resonators, which are small, open cavities in a metal block. Electrons pass by the cavities and cause microwaves to oscillate within, similar to the functioning of a whistle producing a tone when excited by an air stream blown past its opening. The resonant frequency of the arrangement is determined by the cavities' physical dimensions. Unlike other vacuum tubes, such as a klystron or a traveling-wave tube (TWT), the magnetron cannot function as an amplifier for increasing the intensity of an applied microwave signal; the magnetron serves solely as an electronic oscillator generating a microwave signal from direct-current electricity supplied to the vacuum tube. The use of magne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbert Wakefield Banks Skinner
Herbert Wakefield Banks Skinner (7 October 1900 – 20 January 1960) was a British physicist. Biography Skinner was born on 7 October 1900 at 15 Woodville Road, Ealing, London, the only son of George Herbert, director of the shoe firm Lilley & Skinner, and Mabel Elizabeth (née Knight). He was taught at home before starting school, age 9, at Durston House, from where he won a mathematical scholarship to Rugby in 1914. He entered Trinity College, Cambridge in 1919 to read natural sciences and mathematics; he graduated in 1922. Skinner's research career started in the Cavendish Laboratory where, under the supervision of Charles D Ellis, he worked on the β-ray spectrum of radium B and C. Five years later, in 1927, he moved to the physics department of the University of Bristol, which was headed by Arthur M Tyndall and very well equipped. He investigated the excitation potentials of lithium and beryllium, and published the results several years later. This research “pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarendon Laboratory
The Clarendon Laboratory, located on Parks Road within the Science Area in Oxford, England (not to be confused with the Clarendon Building, also in Oxford), is part of the Department of Physics at Oxford University. It houses the atomic and laser physics, condensed matter physics, and biophysics groups within the Department, although four other Oxford Physics groups are not based in the Clarendon Lab. The Oxford Centre for Quantum Computation is also housed in the laboratory. Buildings The Clarendon Laboratory consists of two adjoining buildings, the Lindemann Building (named after Frederick Lindemann, 1st Viscount Cherwell) and the Grade II listed Townsend Building (named after Sir John Sealy Townsend). The Beecroft Building (named after Adrian Beecroft) is now immediately in front of the Lindemann Building, completed in 2018 and designed by Hawkins\Brown, with a budget of approximately £40 million. History The Clarendon is named after Edward Hyde, 1st Earl of Clarend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spark Gap
A spark gap consists of an arrangement of two Conductor (material), conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the potential difference between the conductors exceeds the breakdown voltage of the gas within the gap, a electric spark, spark forms, Ionization, ionizing the gas and drastically reducing its electrical resistance. An electric current then flows until the path of ionized gas is broken or the current reduces below a minimum value called the "holding current". This usually happens when the voltage drops, but in some cases occurs when the heated gas rises, stretching out and then breaking the wiktionary:filament, filament of ionized gas. Usually, the action of ionizing the gas is violent and disruptive, often leading to sound (ranging from a ''snap'' for a spark plug to thunder for a lightning discharge), light, and heat. Spark gaps were used historically in e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Diode
A diode is a two- terminal electronic component that conducts electric 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 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. It has an exponential current–voltage characteristic. 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. The obsolete 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 the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabolic Dish
A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis. The parabolic reflector transforms an incoming plane wave travelling along the axis into a spherical wave converging toward the focus. Conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis. Parabolic reflectors are used to collect energy from a distant source (for example sound waves or incoming star light). Since the principles of reflection are reversible, parabolic reflectors can also be used to collimate radiation from an isotropic source into a parallel beam. In optics, parabolic mirrors are used to gather light in reflecting telescopes and solar furnaces, and project a beam of light in f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernard Lovell
Sir Alfred Charles Bernard Lovell ( ; 31 August 19136 August 2012) was an English physicist and radio astronomer. He was the first director of Jodrell Bank Observatory, from 1945 to 1980. Early life and education Lovell was born at Oldland Common, Bristol, in 1913, the son of local tradesman and Methodist preacher Gilbert Lovell (1881–1956) and Emily Laura, née Adams. Gilbert Lovell was an "authority on the Bible" and, having "studied English literature and grammar", was still "bombarding his son with complaints on points of grammar, punctuation and method of speaking" when Lovell was in his forties. Lovell's childhood hobbies and interests included cricket and music, mainly the piano. He had a Methodist upbringing and attended Kingswood Grammar School. Career and research Lovell studied physics at the University of Bristol obtaining a Bachelor of Science degree in 1934, and a PhD in 1936 for his work on the electrical conductivity of thin films. At this time, he also re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AI Mk
AI most frequently refers to artificial intelligence, which is intelligence demonstrated by machines. Ai, AI or A.I. may also refer to: Animals * Ai (chimpanzee), an individual experimental subject in Japan * Ai (sloth) or the pale-throated sloth, a northern Amazonian mammal species Arts, entertainment and media Works * Ai (album), ''Ai'' (album), a 2004 release by Seraphim * A.I. (song), "A.I." (song), by OneRepublic, 2016 * ''A.I. Artificial Intelligence'', a 2001 American film * ''A.I. Rising'', a 2018 Serbian film * ''AI: The Somnium Files'', a 2019 video game * ''American Idol'', a televised singing contest * ''The American Interest'', a bimonthly magazine (2005–2020) * I (2015 film), ''I'' (2015 film), an Indian Tamil film (initial title: ''Ai'') Other uses in arts and media * A.i. (band), a Californian rock–electroclash group * All in (poker), wagering one's entire stake * Appreciation Index, a British measure of broadcast programme approval * Non-player character, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain Home
Chain Home, or CH for short, was the codename for the ring of coastal early warning radar stations built by the Royal Air Force (RAF) before and during the Second World War to detect and track aircraft. Initially known as RDF, and given the official name Air Ministry Experimental Station Type 1 ( AMES Type 1) in 1940, the radar units were also known as Chain Home for most of their life. Chain Home was the first early warning radar network in the world and the first military radar system to reach operational status. Its effect on the war made it one of the most powerful systems of what became known as the "Wizard War". In late 1934, the Tizard Committee asked radio expert Robert Watson-Watt to comment on the repeated claims of radio death rays and reports suggesting Germany had built some sort of radio weapon. His assistant, Arnold Wilkins, demonstrated that a death ray was impossible but suggested radio could be used for long-range detection. In February 1935, a successful d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Replicas Of WWII TR Tubes, 1946
A replica is an exact (usually 1:1 in scale) copy or remake of an object, made out of the same raw materials, whether a molecule, a work of art, or a commercial product. The term is also used for copies that closely resemble the original, without claiming to be identical. Copies or reproductions of documents, books, manuscripts, maps or art prints are called ''facsimiles''. Replicas have been sometimes sold as originals, a type of fraud. Most replicas have more innocent purposes. Fragile originals need protection, while the public can examine a replica in a museum. Replicas are often manufactured and sold as souvenirs. Not all incorrectly attributed items are intentional forgeries. In the same way that a museum shop might sell a print of a painting or a replica of a vase, copies of statues, paintings, and other precious artifacts have been popular through the ages. However, replicas have often been used illegally for forgery and counterfeits, especially of money and coins, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltage
Voltage, also known as (electrical) potential difference, electric pressure, or electric tension, is the difference in electric potential between two points. In a Electrostatics, static electric field, it corresponds to the Work (electrical), work needed per unit of Electric charge, charge to move a positive Test particle#Electrostatics, test charge from the first point to the second point. In the SI unit, International System of Units (SI), the SI derived unit, derived unit for voltage is the ''volt'' (''V''). The voltage between points can be caused by the build-up of electric charge (e.g., a capacitor), and from an electromotive force (e.g., electromagnetic induction in a Electric generator, generator). On a macroscopic scale, a potential difference can be caused by electrochemical processes (e.g., cells and batteries), the pressure-induced piezoelectric effect, and the thermoelectric effect. Since it is the difference in electric potential, it is a physical Scalar (physics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
