18WuD2x

170 deadbeat • decade capacitor
deadbeat The state wherein a moving body (such
as the pointer of a meter or the voice coil of a
loudspeaker) comes to rest without overswing or
oscillation.
deadbeat galvanometer See DEADBEAT INSTRU-
MENT.
deadbeat instrument A meter or recorder that is
highly damped to ensure that overswing or oscillation
does not occur.
deadbeat meter See DEADBEAT INSTRUMENT.
dead break An unreliable contact of a relay,
caused by insufficient pressure.
dead circuit A circuit that is electrically disabled.
dead end The unused end of a tapped coil (i.e., the
turns between the end of the coil and the last
turn used).
dead-end tower A supporting tower for an antenna
or transmission line that can withstand stresses
caused by loading or pulling.
dead file A computer file that is not in use, but is
being kept in a record.
dead front panel A metal panel that, for safety and
desensitization, is completely insulated from voltage-bearing
components mounted on it; it is often
grounded.
dead interval See DEAD TIME.
dead line A deenergized line or conductor.
dead period See DEAD TIME.
dead room An anechoic room in which acoustic
tests and studies are made.
dead short A short circuit with extremely low (virtually
no) resistance from dc into the radiofrequency
spectrum.
dead space See DEAD BAND.
dead spot 1. An area in which radio waves from a
particular station are not received. 2. On a
vacuum-tube cathode (directly or indirectly
heated), a spot from which no electrons are
emitted.
dead stretch The tendency of insulating materials
to permanently retain their approximate dimensions
after having been stretched.
dead time 1. DOWN TIME. 2. An interval during
which there is no response to an actuating signal.
3. In a computer system, an interval between related
events that is allocated to prevent interference
between the events.
dead volume In a pressure transducer, the zerostimulus
volume of the pressure port cavity.
dead zone See ZONE OF SILENCE.
debatable time Computer time that cannot be
placed in any other category.
debounced switch A switch in sensitive computer
or control systems that has circuitry for eliminating
the electrical effects of bounce (see BOUNCE,
1).
de Broglie waves Electromagnetic waves that are
believed to be associated with moving particles
(such as electrons, protons, and neutrons).
debug 1. To eliminate errors in, and maximize the
efficiency of, a computer program or group of programs.
2. To optimize the design and construction
of electronic equipment.
debugging A process by which engineers eliminate
the flaws in a circuit, machine, or computer program.
debugging aid routine A computer program used
to test other programs.
debugging period The time interval following completion
of a software design, a hardware interconnection,
or the manufacture of a piece of
electronic equipment, during which errors and
imperfections are sought and corrected.
debunching In a velocity-modulated tube, such as
a Klystron, a beamspreading space-charge effect
that destroys electron bunching.
Debye length The maximum distance between an
electron and a positive ion over which the electron
is influenced by the field of the ion.
Debye shielding distance See DEBYE LENGTH.
deca- A prefix that indicates multiplication by 10.
decade 1. A frequency band whose upper limit is 10
times the lower limit. Example: 20 Hz to 200 Hz. 2.
A set of 10 switched or selectable components in
which the total value is 10 times that of individual
values. Example: a decade capacitor. Also called
DECADE BOX. 3. A group, sometimes a unit of access,
of 10 computer storage locations.
decade amplifier An amplifier or preamplifier
whose gain can be adjusted in increments of 10
(×1, ×10, ×100, etc.).
decade box A group of components that provides
values in 10 equal steps selected by a switch or
jacks. For compactness, the components and the
associated hardware are enclosed in a box or can.
See, for example, DECADE CAPACITOR.
decade capacitor A composite capacitor whose
value is variable in 10 equal steps. For example,
the values might be set at 100 picofarads (pF),
200 pF, 300 pF, etc., up to 1000 pF. Compare
DECADE INDUCTOR and DECADE RESISTOR.
0 1 2 3 4 5 6 7 8 9
1
2
3
4 5
decade box
6
7
8
9