Codan Radio Radio Repeater Systems Training Guide - Manual (Page 84)

TRAINING GUIDE | RADIO REPEATER SYSTEM
Appendix J: Glossary of Terms Page 76
Link Repeater
A repeater used to link two or more
repeater sites together.
Megahertz (MHz)
One million Hertz or one million cycles
per second.
Messenger Cable
A well secured cable between a
building and a pole or tower to which
other cables may be attached thereby
reducing the strain.
Microwave
That portion of the frequency spectrum
above 1000 MHz.
Mobile
Equipment designed for vehicular or
portable operation.
Modulate
To vary the amplitude, frequency or
phase of a radio signal, in order to
transmit intelligence.
Noise
Interference caused by either internal or
external sources.
Oscillator
A circuit that produces an alternating
output current of a certain frequency
determined by the characteristics of the
circuit components.
Path Loss
The reduction or attenuation of signal
strength that occurs between the
transmitter and receiver.
Phone Patch
An interconnecting device between a
telephone system and a radio system.
Portable Radio
A completely self-contained two-way
radio.
Propagation
The radiation of electromagnetic waves.
Radio Frequency (RF)
See “frequency”
Radio Receiver
A device which amplifi es radio frequency
signals, separates the intelligence signal
from the RF carrier, amplifi es it, and
converts it back to the original sound
waves.
Radio Spectrum
The entire range of useful radio waves
as classifi ed into nine bands by the
International Telecommunications Union.
Radio Interference
Interference caused by the radio waves
of a station or stations other than that
from which reception is desired.
Radio Wave
A combination of electric and magnetic
fi elds varying at a radio frequency, and
capable of traveling through space at the
speed of light. It is produced by feeding
the output of a radio transmitter to an
antenna.
Random Noise
A term for irregular disturbances of an
electrical nature.
Remote Control
The operation of a base station from a
distance using telephone lines or a radio
circuit.
Repeater
A radio station that automatically re-
broadcasts radio signals that are
received on a specifi c frequency.
Signal
A variable electronic parameter, such as
current or voltage, that is used to convey
information through an electronic circuit
or system.
Signal Path
The route by which intelligence is
conveyed from one point to another.
Signal-To-Noise Ratio
The ratio of one parameter of a desired
signal to the same or corresponding
parameter of the noise.