18WuD2x

ounding • rumble 605
yields 3.5. Compare TRUNCATION. 2. The approximation
of a value to a specified number of
decimal places or significant digits. 3. Smoothing
of the corners of a square wave or sawtooth wave,
resulting in lengthening of the transition time
from one state to another.
rounding error The error resulting from the
rounding of a number (see ROUNDING, 1, 2).
round off
To shorten an otherwise lengthy number
by replacing numerical digits with zeros and increasing
the final nonreplaced digit by 1 if the
leftmost replaced digit is 5 or greater. Thus,
3.141592653 can be rounded off to 3.1416 or
3.14.
round-up A form of numerical approximation, in
which a number with a value of n.5 or greater is
assigned the value n + 1. This is a feature of many
calculators using scientific notation or a fixed
number of decimal places.
R out Symbol for OUTPUT RESISTANCE. (Also, R o .)
route
1. To physically position wires or conducting
circuit paths by planning and deliberation. 2. The
path over which conductors are positioned. 3. A
path over which signals or information can be
carried.
routine
1. In computer operations, the complete
sequence of instructions for performing an operation
(i.e., a program or program segment). 2. A
test or measurement procedure. 3. An assembly
or manufacturing procedure. 4. A standard troubleshooting
procedure.
row In a matrix, a horizontal arrangement or set of
values.
R P 1. Symbol for PLATE RESISTANCE. (Also, r P .)
2. Symbol for POSITIVE RESISTANCE. 3. Symbol
for PARALLEL RESISTANCE. (Also, R par .) 4. Symbol
for PRIMARY RESISTANCE. (Also, R pri .)
R par Symbol for PARALLEL RESISTANCE. (Also,
R P .)
r parameters 1. Device or network parameters expressed
as resistances. 2. Transistor parameters
in terms of resistance values in the equivalent tee
network. Compare G PARAMETERS and H PA-
RAMETERS.
RPG Abbreviation of REPORT PROGRAM GENER-
ATOR.
rpm Abbreviation of revolutions per minute.
rpm meter See ELECTRONIC TACHOMETER and
STROBOSCOPE.
RPN Abbreviation of REVERSE POLISH NOTA-
TION.
R pri Symbol for PRIMARY RESISTANCE. (Also,
R P .)
rps Abbreviation of revolutions per second.
RPT Radiotelegraphic abbreviation of repeat.
R req 1. Symbol for REQUIRED RESISTANCE.
2. Symbol for SCREEN RESISTANCE.
R RF Symbol for RADIO-FREQUENCY RESIS-
TANCE.
R S
Symbol for SOURCE RESISTANCE in a fieldeffect
transistor.
R s 1. Symbol for SERIES RESISTANCE. (Also, R ser .)
2. Symbol for SECONDARY RESISTANCE. (Also,
R sec .)
R sec Symbol for SECONDARY RESISTANCE. (Also,
R s .)
R ser Symbol for SERIES RESISTANCE. (Also, R s .)
RST flip-flop A conventional flip-flop subject to the
operations of reset, set, and trigger.
RST system In the amateur radio service, a
method of reporting signal quality in terms of
readability, strength, and tone.
R sweep In an oscilloscope or spectrum analyzer,
an expanded portion of the trace produced by a
long triggered sweep. It permits detailed analysis
of a small portion of a displayed waveform or frequency
band.
RT 1. Abbreviation of RADIOTELEPHONE. 2. Abbreviation
of ROOM TEMPERATURE.
rt Abbreviation of RIGHT.
R T 1. Symbol for THERMAL RESISTANCE. 2. Symbol
for total resistance. (Also, R t .)
R t Symbol for total resistance.
RTD Abbreviation of RESISTANCE TEMPERA-
TURE DETECTOR.
RTL Abbreviation of RESISTOR-TRANSISTOR
LOGIC.
RTTY Abbreviation of RADIOTELETYPE.
RTZ Abbreviation of RETURN TO ZERO. (Also, RZ.)
Ru Symbol for RUTHENIUM.
rubber
A natural insulating material; an elastomer
exhibiting rapid elastic recovery. Dielectric constant,
2 to 3.5. Dielectric strength, 16 to 50
kV/mm. Also called India rubber. Compare HARD
RUBBER.
rubber-covered wire Wire insulated with a jacket
of rubber.
rubidium Symbol, Rb. A metallic element. Atomic
number, 37. Atomic weight, 85.468.
ruby laser A laser using a ruby rod as the resonant
element.
100-percent
reflector
Ruby crystal
Helical
flash tube
ruby laser
95-percent
reflector
Output
ruby maser A maser in which the resonant material
is ruby.
Ruhmkorff coil See INDUCTION COIL.
rumble 1. Low-frequency acoustical noise of a frequency
below about 50 Hz. 2. Low-frequency
electrical noise in an audio circuit of a frequency