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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...satellite radio
(Encyclopedia)satellite radio: see digital radio. ...radio beacon
(Encyclopedia)radio beacon: see radio range.radio compass
(Encyclopedia)radio compass: see radio range.radio altimeter
(Encyclopedia)radio altimeter: see altimeter.Radio City
(Encyclopedia)Radio City: see Rockefeller Center. ...gamma-ray astronomy
(Encyclopedia)gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...citizens band radio
(Encyclopedia)citizens band radio: see radio.Cassiopeia, in astronomy
(Encyclopedia)Cassiopeia, in astronomy, prominent northern constellation located almost directly opposite the Big Dipper across the north celestial pole. Five bright stars in the constellation form a rough W (or M)...Radio Free Europe
(Encyclopedia)Radio Free Europe (RFE), broadcasting organization established in 1950 with the stated mission of promoting democratic values and institutions. Its original purpose was to broadcast news to countries ...Browse by Subject
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