Search results
Results from the WOW.Com Content Network
Grundig Satellit 400 solid-state, digital shortwave receiver, c. 1986 [1]. Shortwave radio is radio transmission using radio frequencies in the shortwave bands (SW). There is no official definition of the band range, but it always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (approximately 100 to 10 metres in wavelength).
Transmitted via Lahti radio station from 1938 to 1948, Pori shortwave station from 1948 to 1987 and finally then new Pori's shortwave center in Preiviiki district from 1987 to the end of 2006. Known before early 1970s as shortwave service of Finnish Broadcasting Company. Scandinavian Weekend Radio: 2000 Yes France Radio France Internationale ...
A Sangean ATS-909 world band receiver. Shortwave listening, or SWLing, is the hobby of listening to shortwave radio broadcasts located on frequencies between 1700 kHz and 30 MHz (30 000 kHz). [1]
Shortwave broadcasting in the United States allows private ownership of commercial and non-commercial shortwave stations that are not relays of existing AM/MW or FM radio stations, as are common in Africa, Europe, Asia, Oceania except Australia and Latin America. In addition to private broadcasters, the United States also has government ...
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.
Shortwave bands are frequency allocations for use within the shortwave radio spectrum (the upper medium frequency [MF] band and all of the high frequency [HF] band). Radio waves in these frequency ranges can be used for very long distance (transcontinental) communication because they can reflect off layers of charged particles in the ionosphere and return to Earth beyond the horizon, a ...
Before the discovery of electromagnetic waves and the development of radio communication, there were many wireless telegraph systems proposed and tested. [4] In April 1872 William Henry Ward received U.S. patent 126,356 for a wireless telegraphy system where he theorized that convection currents in the atmosphere could carry signals like a telegraph wire. [5]
The R-390A military shortwave radio receiver was the result of a project undertaken by the United States Army Signal Corps in 1954 to replace the existing R-390 receiver then in use. The R-390 had done its job so well that the Corps decided continued use of this type of receiver necessitated an improved, reduced-cost version.