18WuD2x

R 1. Symbol for RESISTANCE. (Also, r.) 2. Radiotelegraph
abbreviation for ROGER. 3. Symbol
for RELUCTANCE. 4. Abbreviation of RADIUS.
r 1. Symbol for ROENTGEN. 2. Symbol for correlation
coefficient. 3. Abbreviation of RADIUS. (Also,
abbreviated R.)
r e Symbol for CLASSICAL ELECTRON RADIUS.
RA 1. Abbreviation of right ascension. 2. Abbreviation
of RANDOM ACCESS.
rabbit ears An indoor antenna, sometimes used
with a television receiver, consisting of two vertical
whips (usually telescoping), the angle between
which is adjustable.
RAC Abbreviation of RECTIFIED ALTERNATING
CURRENT.
R ac Symbol for AC RESISTANCE. (Also, r ac .)
race Incorrect interpretation of the clock pulses by
a digital circuit. Also called racing. The circuit improperly
attempts to do many operations during
one clock pulse, rather than a single operation.
RACES Abbreviation of Radio Amateur Civil Emergency
System.
raceway See WIRE DUCT and WIREWAYS.
rack An upright frame for holding equipment of
RACK-AND-PANEL CONSTRUCTION.
rack-and-panel construction A method of building
electronic equipment on a chassis attached
horizontally or vertically to a vertical panel. After
completion of a unit, the panel is fastened in
place on a RACK. Several such panels fill the
rack.
rack and pinion A device used for mechanical adjustment
of a control, such as the tuning control
in a radio receiver. A gear engages a serrated rod.
As the gear is turned, the rod moves lengthwise.
rack up In computer operations, a way of displaying
data, in which a new line added to the already
completely occupied screen bumps up what has
forgone, thus eliminating the top line.
racon Acronym for radar beacon.
rad 1. A unit of ionizing radiation received by a
body (dose) equal to 0.001 J/kg. 2. Abbreviation
of RADIAC. 3. Abbreviation of RADIAN. 4. Abbreviation
of RADIO. 5. Abbreviation of RADIX.
radar
Straight,
toothed rod
Scale
rack and pinion
Pointer
Shaft
Round,
toothed gear
1. A microwave system for detecting objects
and determining their distance, direction, heading,
speed, and other characteristics. Signals
from the transmitter are reflected back to the
transmitter site by the object, and the reflection
(sometimes along with the transmission) is displayed
on a cathode-ray screen. The name is an
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