18WuD2x

quick-break switch • QWERTY 573
quick-break switch A switch that opens rapidly—
even if its handle or lever is moved slowly by the
operator. This action minimizes arcing and prevents
chatter. Compare QUICK-MAKE SWITCH.
quick charge The process of charging a battery,
such as a nickel-cadmium (NICAD) or nickelmetal-hydride
(NiMH) type, at a relatively rapid
rate, at high charging current. It is sometimes
used to charge a battery from a state of almost total
discharge. Compare TRICKLE CHARGE.
quick-disconnect The characteristic of a connector
that enables its mating halves to be separated
quickly and simply, to break the circuit in which
it is situated.
quickening liquid A solution of mercuric cyanide or
mercuric nitrate, into which objects can be dipped
prior to electroplating with silver. The process ensures
good adhesion of the silver to the object.
quick make An operating characteristic of a
switch, relay, or circuit breaker, whereby the contacts
close rapidly—even when the actuating current
or mechanical force is slow acting.
quick-make switch A switch that closes rapidly—
even if its handle or lever is moved slowly by the
operator. Compare QUICK-BREAK SWITCH.
quick printer A high-speed printer, used with a
data terminal or computer. A relative term, depending
on the user and the application.
quicksilver See MERCURY.
quick-stop control A control on tape recorders and
some dictating machines that allows the operator
to stop the tape, but keep the machine in the play
or record mode. Also called pause control.
QuickTime Trade name (Apple Computer, Inc.) for
system software commonly used in MULTIMEDIA
applications with personal computers.
QUICKTRAN For multiaccess computer systems, a
computer programming language based on FOR-
TRAN and offering facilities, through the use of
remote terminals, for running, testing, debugging,
and compiling programs.
quiescent carrier operation A modulation system
in which the carrier is present only during modulation
(i.e., it is suppressed at all other times).
Also called controlled-carrier transmission.
quiescent-carrier telephony A carrier-current
(wired-wireless) telephone system in which the
carrier is suppressed when there is no voice or
alerting signal.
quiescent component In an electronic device, a
component that is momentarily nonfunctional.
quiescent current Operating current (usually a direct
current) flowing in a circuit or component
during zero-signal or no-drain intervals. Also
called IDLING CURRENT.
quiescent operation Zero-signal operation of a device,
such as a transistor, diode, magnetic amplifier,
or similar component.
quiescent period The no-signal interval during
which equipment is not operating—even though
it is energized.
quiescent point The point on the characteristic
curve of a transistor, diode, or similar device, denoting
the zero-signal operating conditions.
quiescent push-pull Denoting a push-pull stage,
especially an audio power-output amplifier, in
which the direct-current signal is essentially
zero.
quiescent state The inactive, or resting, state of
an active component, such as a transistor or vacuum
tube.
quiescent value The zero-signal value of current
or voltage for any component supplied with operating
power.
quiet AGC See DELAYED AUTOMATIC GAIN CON-
TROL.
quiet automatic gain control See DELAYED AU-
TOMATIC GAIN CONTROL.
quiet automatic volume control See DELAYED
AUTOMATIC GAIN CONTROL.
quiet AVC See DELAYED AUTOMATIC GAIN CON-
TROL.
quiet battery A direct-current source specially designed
and filtered to minimize noise components
in its output.
quieting Noise-voltage reduction in the output of a
frequency-modulation (FM) receiver when an unmodulated
carrier is received. Also called noise
quieting.
quieting level In a frequency-modulation (FM) receiver,
the limiter threshold point.
quieting sensitivity In a frequency-modulation
(FM) receiver, the lowest input-signal amplitude
at which the output signal-to-noise ratio is below
the specified limit.
quiet tuning A system of tuning in which the output
of a receiver is muted until a station is tuned
in properly.
quinary code See BIQUINARY CODE.
quinary counter A decade counter consisting of a
five-stage ring.
quinhydrone electrode A pH meter electrode consisting
of a platinum wire in a solution of quinhydrone
(C 12 H 10 O 4 ). Also see PH METER.
quintillion The number 1,000,000,000,000,
000,000 (10 18 ).
quintupler 1. A rectifier circuit that delivers a direct-current
output voltage equal to about five
times the peak value of the alternating-current
input voltage. 2. A circuit that delivers an output
signal at the fifth harmonic of the input signal.
QWERTY The standard typewriter and computer
keyboard layout. The name is derived from the
first several letters in the top letter row: Q, W, E,
R, T, and Y.