crystal set

noun

an early, tubeless radio receiver using a crystal detector.

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British Dictionary definitions for crystal set

crystal set

noun

an early form of radio receiver having a crystal detector to demodulate the radio signals but no amplifier, therefore requiring earphones

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012