"A"
"B"
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
"P" to PEN", "PER" to "PHOS",
"PHOT" to "POI",
"POL" to "POTA",
"POW" to "PR", "PUL" to "PZ"
PACKET. A sequence of binary
digits, including data and control signals, that is
transmitted and switched as a composite whole, for data communications.
PACKET FORMAT. The structure of data, address, and
control information in a packet.
PACKET SWITCHING. The process of routing and transferring data by means of addressed packets so
that a channel is occupied during the transmission of the packet only, and upon completion of the
transmission the channel is made available for the transfer of other traffic.
PARABOLIC REFLECTOR. An antenna reflector in the shape of a parabola. It converts spherical
wavefronts from the radiating element into plane wavefronts. [Antenna Dictionary]
PARALLAX ERROR. The error in meter readings that results when you look at a meter from some
position other than directly in line with the pointer and meter face. A mirror mounted on the meter face
aids in eliminating parallax error.
PARALLEL CIRCUIT. Two or more electrical devices connected to the same pair of terminals so
separate currents flow through each; electrons have more than one path to travel from the negative to
the positive terminal.
PARALLEL PORT. A port through which two or more data
bits are passed simultaneously, such as all the bits of an 8-bit byte, and that requires as many input
channels as the number of bits that are to be handled simultaneously.
Centronics, IEEE-1284
PARALLEL-NEGATIVE LIMITER. A resistor and diode, connected in series with the input signal, in
which the output is taken across the diode and the negative alternation is eliminated.
PARALLEL-POSITIVE LIMITER. A resistor and diode connected in series with the input signal, in
which the output is taken across the diode and the positive alternation is eliminated.
PARALLEL-RESONANT CIRCUIT. A 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.
PARASITIC ARRAY. An antenna array containing one or more elements not connected to the
transmission line.
PARASITIC ELEMENT. The passive element of an antenna array that is connected to neither the
transmission line nor the driven element.
PARITY. In binary-coded data, a condition that is maintained such that, in any permissible coded
expression, the total number of 1s, or 0s, is always odd or always even.
PASSIVE SATELLITE. A satellite that reflects radio signals back to earth.
PATCH PANEL. A panel used to tie a receiver or transmitter to its associated equipment.
PEAK AMPLITUDE. The maximum value above or below a reference line.
PEAK CURRENT. The maximum current that flows during a complete cycle.
PEAK DETECTION. Detection that uses the amplitude of pam or the duration of pdm to charge a holding
capacitor and restore the original waveform.
PEAKING COIL. An inductor used in an amplifier to provide high-frequency compensation, which
extends the high-frequency response of the amplifier.
PEAK POWER. The maximum value of the transmitted pulse.
PEAK-REVERSE VOLTAGE. The peak ac voltage that a rectifier tube will withstand in the reverse
direction.
PEAK-TO-PEAK. The measure of absolute magnitude of an ac waveform, measured from the greatest
positive alternation to the greatest negative alternation.
PEAK VALUE. The maximum instantaneous value of a varying current, voltage, or power. It is equal to
1.414 times the effective value of a sine wave.
PEAK VOLTAGE. The maximum value present in a varying or alternating voltage. This value may be
positive or negative.
PENTODE TUBE. A five-electrode electron tube containing a plate, a cathode, a control grid, and two
grids.
Next set of "P" Terms
