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AMES Type 84
The AMES Type 84, also known as the Microwave Early Warning or MEW, was a 23 cm wavelength early warning radar used by the Royal Air Force (RAF) as part of the Linesman/Mediator radar network. Operating in the L-band gave it improved performance in rain and hail, where the primary AMES Type 85 radar's performance dropped off. It operated beside the Type 85 and RX12874 in Linesman, and moved to the UKADGE system in the 1980s before being replaced during UKADGE upgrades in the early 1990s. The Type 84 had a decade-long development period that saw the system being repeatedly redesigned. It was first conceived in 1951 during the ROTOR program as a megawatt-powered S-band system that would replace the WWII-era Chain Home radars for early warning. But an experimental system developed at the Royal Radar Establishment (RRE) offered similar performance and would be available long before the MEW's 1957 target date. Put into operation as the AMES Type 80 in 1953, the immediate need for M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marconi Company
The Marconi Company was a British telecommunications and engineering company that did business under that name from 1963 to 1987. Its roots were in the Wireless Telegraph & Signal Company founded by Italian inventor Guglielmo Marconi in 1897, which underwent several changes in name after mergers and acquisitions. The company was a pioneer of wireless long distance communication and mass media broadcasting, eventually becoming one of the UK's most successful manufacturing companies. In 1999, its defence equipment manufacturing division, Marconi Electronic Systems, merged with British Aerospace (BAe) to form BAE Systems. In 2006, financial difficulties led to the collapse of the remaining company, with the bulk of the business acquired by the Swedish telecommunications company, Ericsson. History Naming history *1897–1900: The Wireless Telegraph & Signal Company *1900–1963: Marconi's Wireless Telegraph Company *1963–1987: Marconi Company Ltd *1987–1998: GEC-Marconi Ltd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinotron
A backward wave oscillator (BWO), also called carcinotron or backward wave tube, is a vacuum tube that is used to generate microwaves up to the terahertz range. Belonging to the traveling-wave tube family, it is an oscillator with a wide electronic tuning range. An electron gun generates an electron beam that interacts with a slow-wave structure. It sustains the oscillations by propagating a traveling wave backwards against the beam. The generated electromagnetic wave power has its group velocity directed oppositely to the direction of motion of the electrons. The output power is coupled out near the electron gun. It has two main subtypes, the M-type (M-BWO), the most powerful, and the O-type (O-BWO). The output power of the O-type is typically in the range of 1 mW at 1000 GHz to 50 mW at 200 GHz. Carcinotrons are used as powerful and stable microwave sources. Due to the good quality wavefront they produce (see below), they find use as illuminators in terahertz ... [...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 currently in microwave ovens and linear particle accelerators. It 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 oscillator, generating a microwave signal from direct current electricity supplied to the vacuum tube. The use of magnetic fields as a means to control the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Detector
A crystal detector is an obsolete electronic component used in some early 20th century radio receivers that consists of a piece of crystalline mineral which rectifies the alternating current radio signal. It was employed as a detector (demodulator) to extract the audio modulation signal from the modulated carrier, to produce the sound in the earphones. It was the first type of semiconductor diode, and one of the first semiconductor electronic devices. The most common type was the so-called cat's whisker detector, which consisted of a piece of crystalline mineral, usually galena (lead sulfide), with a fine wire touching its surface. Greenleaf Whittier Pickard, ''Detector for Wireless Telegraphy and Telephony'', filed: 21 June 1911, granted: 21 July 1914 The "asymmetric conduction" of electric current across electrical contacts between a crystal and a metal was discovered in 1874 by Karl Ferdinand Braun. Crystals were first used as radio wave detectors in 1894 by Jagadish C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Research Establishment
The Telecommunications Research Establishment (TRE) was the main United Kingdom research and development organization for radio navigation, radar, infra-red detection for heat seeking missiles, and related work for the Royal Air Force (RAF) during World War II and the years that followed. It was regarded as "the most brilliant and successful of the English wartime research establishments" under "Rowe, who saw more of the English scientific choices between 1935 and 1945 than any single man." The name was changed to Radar Research Establishment in 1953, and again to the Royal Radar Establishment in 1957. This article covers the precursor organizations and the Telecommunications Research Establishment up to the time of the name change. The later work at the site is described in the separate article about RRE. History TRE is best known for work on defensive and offensive radar. TRE also made substantial contributions to radio-navigation and to jamming enemy radio-navigation. Rad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Olympus (Cyprus)
Olympus, or Chionistra, ( el, Όλυμπος ''or'' Χιονίστρα; tr, Olimpos Tepesi) at , is the highest point in Cyprus. It is located in the Troodos Mountains of Cyprus. Mount Olympus peak and the "Troodos Square" fall under the territory of Platres in Limassol District. A British long range radar currently operates at Mount Olympus' peak. It has a highland warm-summer mediterranean climate. The Mount Olympus Ski resort consists of the Sun Valley and North Face areas. Each area has its own ski lifts and runs, operated by the Cyprus Ski Club: * Aphrodite or Sun Valley I, with a 125m T-bar ski lift and beginner-level slopes * Hermes or Sun Valley II, with a 140m T-bar ski lift and intermediate-level slopes * Dias/Zeus or North Face I, with a 380m chairlift and advanced-level slopes * Hera or North Face II, with a 262m T-bar ski lift and beginner-level slopes In the Sun Valley area there is a 55m rope tow baby lift as well. Writing in the late first century BC or first c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprus
Cyprus ; tr, Kıbrıs (), officially the Republic of Cyprus,, , lit: Republic of Cyprus is an island country located south of the Anatolian Peninsula in the eastern Mediterranean Sea. Its continental position is disputed; while it is geographically in Western Asia, its cultural ties and geopolitics are overwhelmingly Southern European. Cyprus is the third-largest and third-most populous island in the Mediterranean. It is located north of Egypt, east of Greece, south of Turkey, and west of Lebanon and Syria. Its capital and largest city is Nicosia. The northeast portion of the island is ''de facto'' governed by the self-declared Turkish Republic of Northern Cyprus, which was established after the 1974 invasion and which is recognised as a country only by Turkey. The earliest known human activity on the island dates to around the 10th millennium BC. Archaeological remains include the well-preserved ruins from the Hellenistic period such as Salamis and Kourion, and Cypr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RAF Bawdsey
Royal Air Force Bawdsey or more simply RAF Bawdsey is a former Royal Air Force station situated on the eastern coast in Suffolk, England. Also known as Bawdsey Research Station (BRS), the first Chain Home radar station was built there, characterized by eight tall masts, four for transmitting and four for receiving. When the research group moved to Dundee in September 1939, the radar station was left active under the name RAF Bawdsey. The site later hosted a Bristol Bloodhound surface-to-air missile station until 1990, with the station closing in 1991. History Bawdsey Manor, dating from 1886, was taken over in March 1936 by the Air Ministry for developing the Chain Home (CH) RDF (radar) system. The station's Superintendent was initially Robert Watson-Watt, later followed by A.P. Rowe. The experimental radar station was located just northeast of the Manor, about distant. When war was declared in September 1939, fears of a possible commando raid on the group led to the developme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Agility
Frequency agility is the ability of a radar system to quickly shift its operating frequency to account for atmospheric effects, jamming, mutual interference with friendly sources, or to make it more difficult to locate the radar broadcaster through radio direction finding. The term can also be applied to other fields, including lasers or traditional radio transceivers using frequency-division multiplexing, but it remains most closely associated with the radar field and these other roles generally use the more generic term "frequency hopping". Description Jamming Radar systems generally operate by sending out short pulses of radio energy and then turning off the broadcaster and listening for the returning echoes from various objects. Because efficient signal reception requires careful tuning throughout the electronics in the transceiver, each operating frequency required a dedicated transceiver. Due to the size of the tube-based electronics used to construct the transceivers, early ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Yeoman
The AMES Type 85, also known by its rainbow code Blue Yeoman, was an extremely powerful early warning (EW) and fighter direction (GCI) radar used by the Royal Air Force (RAF) as part of the Linesman/Mediator radar network. First proposed in early 1958, it was eleven years before they became operational in late 1968, by which time they were already considered obsolete. The Type 85 remained the RAF's primary air defense radar until it was replaced by Marconi Martello sets in the late-1980s as part of the new IUKADGE network. In the 1950s the RAF deployed the ROTOR reporting network, and later improved this system with the AMES Type 80 radar. While these were being built, the carcinotron radar jammer was tested against it and found to completely blank out its display. At first, it was feared the carcinotron would render all long-range radars useless, but over time a number of new concepts emerged to deal with this threat. Among them was the Blue Riband radar, which used a dozen 8&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
