AI-6
PULSING—Allowing oscillations to occur for a specific period of time only during selected
intervals.
QUANTIZED WAVE—A wave created by arbitrarily dividing the entire range of amplitude (or
frequency, or phase) values of an analog wave into a series of standard values. Each sample
takes the standard value nearest its actual value when modulated.
QUANTIZING NOISE—A distortion introduced by quantizing the signal.
RADAR DETECTOR—A detector which, in its simplest form, only needs to be capable of
producing an output when rf energy (reflected from a target) is present at its input.
RATIO DETECTOR—A detector that uses a double-tuned transformer to convert the
instantaneous frequency variations of the fm input signal to instantaneous amplitude
variations.
RATIO OF TRANSMITTED POWERS—The power ratio (fsk verses AM) that expresses the
overall improvement of fsk transmission when compared to AM under rapid-fading and
high-noise conditions.
REACTANCE TUBE—A tube connected in parallel with the tank circuit of an oscillator.
Provides a signal that will either lag or lead the signal produced by the tank.
REACTANCE-TUBE MODULATOR—An fm modulator that uses a reactance tube in parallel
with the oscillator tank circuit.
REGENERATIVE DETECTOR—A detector circuit that produces its own oscillations,
heterodynes them with an incoming signal, and detects them.
REST FREQUENCY—The carrier frequency during the constant-amplitude portions of a phase
modulation signal.
REST TIME (rt)—The time when there is no pulse or nonpulse.
ROTARY GAP—Similar to a mechanically driven switch. Used to discharge a pulse-forming
network.
SENSITIVITY OF A MICROPHONE—Efficiency of a microphone. Describes micro- phone
power delivered to a matched-impedance load as compared to the sound level being
converted. Usually expressed in terms of the electrical power level.
SERIES-DIODE DETECTOR—The semiconductor diode in series with the input voltage and
the load impedance. Sometimes called a voltage-diode detector.
SHUNT—Means the same as parallel or to place in parallel with other components.
SHUNT-DIODE DETECTOR—A diode detector in which the diode is in parallel with the input
voltage and the load impedance. Also known as a current detector because it operates with
smaller input levels.
SIGNAL DISTORTION—Any unwanted change to the signal.
SIGNIFICANT SIDEBANDS—Those sidebands with significantly large amplitude.
