The typical shortwave radio receiver design is a superheterodyne receiver. Serious hobbyists may use communications receivers and outdoor antenna located away from electrical noise sources, such as a dipole made from wire and insulators. Modern shortwave radio receivers are relatively inexpensive and easily accessible, and many hobbyists use portable "world band" receivers and built-in telescopic antennas. Radios for shortwave reception generally have higher performance than those intended for the local mediumwave, longwave or FM broadcast band, since dependable reception of shortwave signals requires a radio with increased sensitivity, selectivity, dynamic range and frequency stability. They typically include features that enable increased sensitivity and selectivity. Shortwave receivers known as communications receivers are typically larger table top sets used in amateur radio, commercial, and military installations, and by serious hobbyists. Modern battery-operated portable shortwave radio receivers often called world radio or world band receivers are marketed primarily to those wishing to receive international broadcasts, and are offered in a range of compact "travel size" to smaller "pocket size" units. Modern Icom RC-9500 shortwave communications receiver And miniaturization of components along with integrated circuits enabled the manufacture of small, portable shortwave receivers with adequate sensitivity to deliver satisfactory shortwave reception. Synchronous detection improved audio fidelity and stability. Solid state components minimized frequency drift. Direct digital tuning eliminated the guesswork and imprecision inherent in analog tuners. Īs shortwave receivers evolved, they gained a number of improvements over their early counterparts. The Magnavox model AW-100 was introduced in 1957 and was among the first commercial fully transistorized shortwave radio receivers, along with the Trans-Oceanic Royal 1000 (1957) and Trans-World Portable T-9 Code 126 (1958). ![]() Shortwave receiver designs had traditionally employed vacuum tubes, but solid state circuit designs began to emerge in the 1950s. įollowing development of several prototypes between 19, Zenith introduced the Model 7G605 Trans-Oceanic 'Clipper' in 1942, an early portable shortwave receiver marketed to consumers. By 1936 it was estimated that 100 percent of console models and 65 percent of table model radios were able to receive shortwave broadcasts. 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. In 1936, Hammarlund introduced their " Super-Pro" superheterodyne shortwave 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. 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. Other notable early shortwave receivers included Pilot Radio's "Super Wasp" line of regenerative receivers. 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. Such converters were generally found unsatisfactory in performance, and so dedicated shortwave receiving sets soon appeared on the market. 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. Grundig Satellit 210 portable receiver, circa 1969–1971 featuring early solid state circuitry.
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