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Concept
Shortwave radio receiver
Résumé
A shortwave radio receiver is a radio receiver that can receive one or more shortwave bands, between 1.6 and 30 MHz. A shortwave radio receiver often receives other broadcast bands, such as FM radio, Longwave and Mediumwave. Shortwave radio receivers are often used by dedicated hobbyists called shortwave listeners.
While home built shortwave receivers had been used by amateur radio operators and radio experimenters prior to World War I, the first time shortwave radio reception was available to the general public was through the use of shortwave frequency converters sold as accessories to broadcast-band radio sets during the mid 1920s. Such converters were generally found unsatisfactory in performance, and so dedicated shortwave receiving sets soon appeared on the market. National Radio Company introduced the SW-2 "Thrill box" shortwave regenerative receiver in 1927, and later offered improved models, such as the highly regarded SW-3. Other notable early shortwave receivers included Pilot Radio's "Super Wasp" line of regenerative receivers.
E.H. Scott Radio Laboratories offered its superheterodyne "World's Record" shortwave receiver kit in the late 1920s, and In 1931 Hammarlund introduced the "Comet Pro", the first fully assembled commercial shortwave superheterodyne receiver. Hallicrafters introduced the "Super Skyrider" in 1935, a superheterodyne shortwave receiver available in several different models that covered the broadcast band up to 30 MHz. In 1936, Hammarlund introduced their "Super-Pro" superheterodyne shortwave receiver.
Superheterodyne receiver circuits soon essentially replaced all previous receiver designs, and radio manufacturers such as RCA, Zenith, Philco, Emerson, and Stromberg-Carlson offered consumers table or console model "all wave" sets that could receive both mediumwave and shortwave bands. By 1936 it was estimated that 100 percent of console models and 65 percent of table model radios were able to receive shortwave broadcasts.
Source officielle
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