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radio

(Encyclopedia)CE5 A. AM transmitter B. AM receiver radio, transmission or reception of electromagnetic radiation in the radio frequency range. The term is commonly applied also to the equipment used, especially...

digital radio

(Encyclopedia)digital radio, audio broadcasting in which an analog audio signal is converted into a digital signal before being transmitted; also known as digital audio broadcasting (DAB) and high-definition radio....

satellite radio

(Encyclopedia)satellite radio: see digital radio. ...

radio altimeter

(Encyclopedia)radio altimeter: see altimeter.

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

radio beacon

(Encyclopedia)radio beacon: see radio range.

Radio City

(Encyclopedia)Radio City: see Rockefeller Center. ...

radio compass

(Encyclopedia)radio compass: see radio range.

radio frequency

(Encyclopedia)radio frequency, range of electromagnetic waves with a frequency or wavelength suitable for communication uses. Some of these waves serve as carriers of the lower-frequency audio waves; others are mod...

radio range

(Encyclopedia)radio range, geographically fixed radio transmitter that radiates coded signals in all directions to enable aircraft and ships to determine their bearings. An aircraft or ship can determine its line o...