18WuD2x

parallel circuit • parallel operation 513
parallel circuit A circuit in which the components
are connected across each other (i.e., so that the
circuit segment could be drawn showing component
leads bridging common conductors as rungs
would across a ladder). Compare SERIES CIR-
CUIT.
parallel-component amplifier An amplifier stage
in which the active devices (transistors or vacuum
tubes) are connected in parallel with each
other for increased power output. Also see PAR-
ALLEL CIRCUIT.
parallel-component oscillator An oscillator stage
in which transistors are connected in parallel
with each other for increased power output. Also
see PARALLEL CIRCUIT.
parallel computer A computer equipped to handle
more than one program at a time, but not
through the use of multiple programming or
time-sharing.
parallel-cut crystal See Y-CUT CRYSTAL.
parallel-diode half-wave rectifier See PARALLEL
LIMITER.
parallel-fed amplifier An amplifier circuit in which
the direct-current operating voltage is applied in
parallel with the alternating-current output voltage.
Also see PARALLEL FEED.
parallel-fed oscillator An oscillator circuit in
which the direct-current operating voltage is applied
in parallel with the alternating-current output
voltage. Also see PARALLEL FEED.
parallel feed 1. The presentation of parallel alternating-current
(ac) and direct-current (dc) voltages
to a device. 2. The presentation of a dc
operating voltage in parallel with the ac output
voltage of a device (as in a parallel-fed amplifier or
oscillator). Also see SHUNT FEED.
parallel gap welding A welding technique using
two electrodes separated by a gap.
parallel gate circuit 1. A gate circuit using two
bipolar transistors with parallel-connected collectors
and emitters, and a common collector resistor.
The input signal is applied to one base, and
the control signal to the other. 2. A gate circuit
using two field-effect transistors with parallelconnected
drains and sources, and a common
drain resistor. The input signal is applied to one
gate, and the control signal to the other.
parallel inductance An inductance connected in
parallel (shunt) with some other component.
parallel inductors Inductors connected in parallel
and separated or oriented to minimize the effects
of mutual inductance. Also see PARALLEL CIR-
CUIT.
parallel inverse feedback In a single-ended audio
amplifier circuit, a simple system for obtaining
negative feedback: A high resistance is connected
from the output-transistor collector or drain to
the driver-transistor collector or drain.
parallel limiter A limiter (clipper) circuit in which
the diode is in parallel with the signal. Compare
SERIES LIMITER.
Positive limiting
0 0
v in
Negative limiting
0 0
v in
parallel limiter
parallel-line tuning At ultra-high frequencies
(UHF) and microwave frequencies, the use of two
parallel wires or rods for tuning. A straight shortcircuiting
bar is slid along the wires to accomplish
tuning.
parallelogram A two-dimensional geometric figure
that has four sides. Opposite pairs of sides are parallel.
Opposite interior angles have equal measure.
y
x
x
parallelogram
parallelogram of vectors A graphic device for finding
the sum of two vectors. A parallelogram is
constructed for which the two vectors are adjacent
sides. The sum of the vectors is represented
by the diagonal of the parallelogram.
parallel operation In computer operations, the simultaneous
transmission of all bits in a multibit
word over individual lines, as compared with the
serial transmission of a word bit by bit.
v out
v out
y