plural of software defined radio

plural of wind-up radio

The transmission of speech using modulated radio waves

(dated) A small portable radio receiver having transistors rather than thermionic valves; popular from the late 1950s.

Synonym of crystal set

(chiefly Britain, informal) Radio (sound broadcasting), considered as old-fashioned compared to television.

(astronomy) A device for observing astronomical sources of radio waves, normally having one or more large parabolic dishes.

(physics) electromagnetic radiation having a wavelength between about .5 centimeters and 30,000 meters; used for the broadcasting of radio and television signals.

Broadcasting without having the necessary license that covers the territory where the signals are received.

(colloquial) The hobby of amateur radio communication.