PARALLEL-RESONANT CIRCUITA resonant circuit in which the source voltage is connected
across a parallel circuit (formed by a capacitor and an inductor) to furnish a high impedance to the
frequency at which the circuit is resonant. Often referred to as a tank circuit.
PERIODIC WAVEA waveform that undergoes a pattern of changes, returns to its original pattern,
and then repeats the same pattern of changes. Examples are square waves, rectangular waves, and
POSITIVE CLAMPERThe lower extremity of the output waveshape is clamped to a dc potential of 0
PULSESignal characterized by a rapid rise and decay from an initial level.
PULSE OSCILLATORA sine-wave oscillator that is turned on and off at specific times. Also known
as a ringing oscillator.
PULSE-REPETITION FREQUENCY (PRF)The number of times in 1 second that a waveform
PULSE-REPETITION RATE (PRR)Same as Pulse-Repetition Frequency (prf).
QFigure of merit (efficiency) of a circuit or coil. Ratio of inductive reactance to resistance.
QUIESCENT STATETime during which a tube or transistor of an electrical circuit is not performing
its active function.
RC CONSTANTTime constant of a resistor-capacitor circuit. Equal in seconds to the resistance value
multiplied by capacitance value.
RC DIFFERENTIATORAn RC circuit in which the output is taken from the resistor.
RC INTEGRATORAn RC circuit in which the output is taken from the capacitor.
RC NETWORKA circuit containing resistances and capacitances arranged in a particular manner to
perform a specific function.
RC OSCILLATORAn oscillator in which the frequency is determined by resistive and capacitive
REGENERATIVE FEEDBACKThe process by which a portion of the output power of an amplifying
device is fed back to reinforce the input.
RESONANCEThe condition in a circuit containing inductance and capacitance in which the inductive
reactance is equal and opposite to the capacitive reactance. This condition occurs at only one
frequency and the circuit in that condition is said to be in resonance. The resonant frequency can be
changed by varying the values of either the capacitance or inductance.
RESONANT CIRCUITA circuit that contains both inductance and capacitance and is resonant at one
frequency (XL = XC).
RESONANT FREQUENCYThat frequency in a given resonant circuit at which the inductive and
capacitive values are equal and cancel each other.
RL DIFFERENTIATORAn RL circuit in which the output is taken from the inductor.