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RECEIVER—(1) The object that responds to the wave or disturbance. Same as DETECTOR [10]. (2)
Equipment that converts electromagnetic energy into a visible or an audible form [17]. (3) In radar, a
unit that converts RF echoes to video and/or audio signals [18].
RECEIVER SENSITIVITY—(1) The degree to which a receiver can usefully detect a weak signal. (2)
The lower limit of useful signal input to the receiver [18].
RECEIVER TRANSFER SWITCHBOARD—Equipment used to transfer receiver audio outputs to
remote control station audio circuits [17].
RECEIVING ANTENNA—The device used to pick up the RF signal from space [10].
RECEIVING END—See OUTPUT END [10].
RECEPTION—The instant when an electromagnetic wave passes through a receiver antenna and induces a
voltage in that antenna [17].
RECIPROCAL (OF A QUANTITY)—The value obtained by dividing the number 1 by that quantity [1].
RECIPROCITY—The property of interchangeability of the same antenna for transmitting and receiving
[10] [11].
RECOVERY TIME—In a radar, the time interval between the end of the transmitted pulse and the time
when echo signals are no longer attenuated by the tr gap [18].
RECTIFIER—A device used to convert ac to pulsating dc [3] [6] [7].
RECTANGULAR-COORDINATE GRAPH—A graph in which straight-line axes (horizontal and
vertical) are perpendicular [10].
RED—The reference color of equipment that passes classified information. It normally refers to patch
panels [17].
REFERENCE LINE—The position of zero displacement in a wave [10].
REFERENCE POINT—A point in a circuit to which all other points in the circuit are compared [1].
REFLECTED WAVE—(1) The wave that reflects back from a medium. (2) The wave moving back to the
source from the termination of a transmission line after reflection has occurred [10].
REFLECTING OBJECT—In radar a air or surface contact that provides an echo [18].
REFLECTION WAVES—Waves that are neither transmitted nor absorbed, but are reflected from the
surface of the medium they encounter [10].
REFLECTOR—The parasitic element of an array that causes maximum energy radiation in a direction
toward the driven element [10].
REFLEX KLYSTRON—A klystron with a reflector (repeller) electrode in the place of a second resonant
cavity used to redirect the velocity-modulated electrons back through the cavity that produced the
modulation [11]. (2) A microwave oscillator that is tuned by changing the repealer voltage [18].
REFRACTION—The changing of direction of a wave as it leaves one medium and enters another medium
of a different density [10] [18].
