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Hedy Lamarr (/ ˈ h ɛ d i /; born Hedwig Eva Maria Kiesler; November 9, 1914 [a] – January 19, 2000) was an Austrian-born American actress and inventor. After a brief early film career in Czechoslovakia, including the controversial erotic romantic drama Ecstasy (1933), she fled from her first husband, Friedrich Mandl, and secretly moved to Paris.
Most of today's radar detectors detect signals across a variety of wavelength bands: usually X, K, and K a. In Europe the K u band is common as well. The past success of radar detectors was based on the fact that radio-wave beams can not be narrow-enough, so the detector usually senses stray and scattered radiation, giving the driver time to ...
Based on this, Page, Taylor, and Young are usually credited with building and demonstrating the world's first pulsed radar. An important subsequent development by Page was the duplexer , a device that allowed the transmitter and receiver to use the same antenna without overwhelming or destroying the sensitive receiver circuitry.
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Radar detectors are built around a superheterodyne receiver, which has a local oscillator that radiates slightly. It is therefore possible to build a radar-detector detector, which detects such emissions (usually the frequency of the radar type being detected, plus about 10 MHz for the intermediate frequency).
The results were encouraging, and the government immediately commissioned construction of 17 additional stations. This became Chain Home, the array of fixed radar towers on the east and south coasts of England. [20] [21] By the start of World War II, 19 were ready for the Battle of Britain, and by the end of the war, over 50 had been built. The ...
The FuG 227 Flensburg was a German passive radar receiver developed by Siemens & Halske and introduced into service in early 1944. It used wing and tail-mounted dipole antennae and was sensitive to the mid-VHF band frequencies of 170–220 MHz, subharmonics of the Monica radar's 300 MHz transmissions.
III radars, which had been developed from the H2S equipment. This U-boat is equipped with the Fliege and Tunis antennas. The Naxos radar warning receiver was a World War II German countermeasure to S band microwave radar produced by a cavity magnetron. Introduced in September 1943, it replaced Metox, which