18WuD2x

606 rumble • R-Y signal
below about 50 Hz. 3. Vibrations that can occur
in a poorly designed or malfunctioning phonograph
turntable.
rumble filter An audio high-pass filter having
sharp cutoff below 50 Hz, for eliminating rumble
arising from irregularities in the rotation of a
phonograph turntable. Also see RUMBLE, 3.
run 1. The execution of a computer routine or program.
2. To execute a routine or program. 3. To
cause a routine or program to be executed. 4. A
command that causes a routine or program to be
executed.
runaway
In a current-carrying circuit or device, especially
a semiconductor, a rapid increase in current
that causes the temperature to rise, in turn
resulting in a further increase in current. Unless
preventive measures are taken, this will ultimately
damage or destroy the component.
run chart In computer operations, a flowchart
showing the organization and order of pertinent
programs to be run.
running accumulator A computer storage unit
having registers linked so that data is transferred
unidirectionally from one to the other, and in
which only one register is accessible from the outside.
running open 1. The condition of a mechanical
teleprinter running continuously in the absence
of a signal. The teleprinter operates, but nothing
is printed; this keeps the machine in synchronization.
2. Operation of a transmitter at the
maximum rated level of input or output power.
running-time meter See ELAPSED-TIME METER.
run time 1. The period of time during which a
computer program is executed. 2. The length of
time required for a computer program to be executed.
rupture 1. The usually rapid and violent tearing
apart, or breaking through, of an insulating material
subjected to excessive voltage. 2. The clean
opening of relay, circuit-breaker, or switch contacts
to interrupt a current-carrying circuit.
rush Broadband audio background noise, such as
that arising from superheterodyne receivers and
high-gain amplifiers. Its name is derived from resemblance
to the gentle rushing of wind. Compare
HISS, 1, 2.
ruthenium Symbol, Ru. A rare metallic element.
Atomic number, 44. Atomic weight, 101.07.
rutherford
Abbreviation, rd. A unit of radioactivity
equal to 10 6 disintegrations per second (2.7 × 10 –5
curie). Also see KILORUTHERFORD, MEGA-
RUTHERFORD, MICRORUTHERFORD, and
MILLIRUTHERFORD.
Rutherford atom An early concept of the nature of
the atom, proposed by Rutherford in 1912. In this
model, negatively charged electrons orbit a central,
positively charged nucleus in a manner similar
to the way planets orbit the sun. Compare
BOHR ATOM.
rutherfordium Symbol, Rf. Also called unnilquadium
(Unq) and kurchatovium (Ku). Atomic number, 104.
The most common isotope has atomic weight 261.
Classified as a transition metal. It has a half-life on
the order of a few seconds to a few tenths of a second
(depending on the isotope), is human-made,
and is not known to occur in nature.
RW Abbreviation of radiological warfare.
R x Symbol for unknown resistance.
RY Abbreviation of RELAY.
ryotron A form of inductive semiconductor switch,
operated at cold temperatures to maximize conductivity.
R-Y signal In a color-television circuit, the signal
representing primary red (R) minus luminance
(Y). A primary red signal is obtained when the
R-Y signal is combined with the luminance (Y)
signal. Compare B-Y SIGNAL and G-Y SIGNAL.