Short waves

Short waves, electromagnetic (radio) waves having a wavelength from about 32 to 328 ft (10 to 100 m) and a frequency between about 3,000 and 30,000 kilohertz—shorter and of higher frequency than the wavelengths of amplitude modulation (AM) transmissions. Short waves are used to carry international broadcasting, EM (frequency modulation) radio stations, and transoceanic telephone calls. Shortwave radios that can receive and transmit signals are used by pilots, the police, and amateur and citizens band operators.

See also: Radio, amateur.