FREQUENCY SYNTHESIZER(1) A frequency source of high accuracy . (2) A bank of oscillators
in which the outputs can be mixed in various combinations to produce a wide range of frequencies .
FRONT-TO-BACK RATIOThe ratio of the energy radiated in the principal direction compared to the
energy radiated in the opposite direction .
FULL-WAVE RECTIFIERA circuit that uses both positive and negative alternations in an alternating
current to produce direct current  .
FULL-WAVE VOLTAGE DOUBLERConsists of two half-wave voltage rectifiers and is used to
reduce the output ripple amplitude .
FUNCTIONA specific purpose of an entity; its characteristic action .
FUNDAMENTAL FREQUENCYThe basic frequency or first harmonic frequency .
FUSED-ALLOY JUNCTIONSee ALLOYED-JUNCTION .
GAIN(1) The ratio between the amount of energy propagated from an antenna that is directional
compared to the energy from the same antenna that would be propagated if the antenna were not
directional . (2) Any increase in the strength of a signal .
GAIN-BANDWIDTH PRODUCTThe number that results when the gain of a circuit is multiplied by the
bandwidth of that circuit. For an operational amplifier, the gain-bandwidth product for one
configuration will always equal the gain-bandwidth product for any other configuration of the same
GALENAA crystalline form of lead sulfide used in early radio receivers .
GALVANOMETERA meter used to measure small values of current by electromagnetic or
electrodynamic means   .
)The emitter-to-base current ratio in a common-collector configuration .
GANGED TUNINGThe process used to tune two or more circuits with a single control .
GASOne of the three states of matter; it has no fixed form or volume .
GATEAs applied to logic circuitry, one of several different types of electronic devices that will provide a
particular output when specified input conditions are satisfied. Also, a circuit in which a signal switches
another signal on or off .
GATED AGCCircuit that permits automatic gain control to function only during short time intervals
GATED-BEAM DETECTORAn FM demodulator that uses a special gated-beam tube to limit, detect,
and amplify the received FM signal. Also known as a quadrature detector .
GATINGThe process of selecting those portions of a wave that exist during one or more selected time
intervals or that have magnitudes between selected limits. Also, the application of a specific waveform
to perform electronic switching .