DETECTOR, that part of a wireless circuit whose function is to pick up or detect the electric oscillations which are set up in the antenna (q.v.) by the electromagnetic vibrations. (See WIRELESS TELEGRAPHY AND TELEPHONY.) As used in a radio receiving ap paratus it is connected to a circuit carrying current of radio fre quency, and translates the radio-frequency power into a form suit able for the operation of an indicator. This translation may be effected either by the conversion of the radio-frequency power into some other form or by the control of local power. The in dicator may be a telephone receiver, loudspeaker, relaying device, tape recorder, etc. The most common type of detector is a vacuum tube operated on a non-linear portion of its characteristic curve, thereby converting a modulated radio-frequency current into a modulated direct current.