MT-4E VHF & UHF Receiver & Transmitter Instruction Manual
IM08-MT-4E-TXRX-P1162
Glossary of Terms
52
Modulation
A controlled variation of any property of a
carrier wave for the purpose of transferring
information.
MSB
Most Significant BIT.
NAC
Network Access Code. A 12-bit field
identifying the network of the radio message.
Typically used to steer repeater functions.
PTT
Push-to-Talk – the switch on a subscriber
unit which, when pressed, causes the
subscriber unit to transmit.
QPSK
Quadrature Phase Shift Keying – modulation
technique. PSK using four-phase states.
RF
Radio Frequency.
Signal
The detectable transmitted energy which
carries information from a transmitter to a
receiver.
SINAD
SIgnal-plus-Noise-and-Distortion to
noise-and-distortion ratio.
Squelch
A radio circuit that eliminates noise from
the speaker when no transmitted signal
is present.
Subscriber Unit
A mobile or portable radio unit used in a
radio system.
TGID
Talk Group Identifier. A 16-bit field
identifying the talk group of the radio
message.
TIA
Telecommunications Industry
Association.
Time-Out Timer
A function that limits the transmission
period to a pre-defined time. The user
will automatically stop transmitting when
the timer goes off after the pre-defined
time.
Trunked (System)
Systems with full-feature sets in which
all aspects of radio operation—including
RF channel selection and access—are
centrally managed.
UCM
Universal Cryptographic Module
UDB
Universal Daughter Board
VOCODER (Voice-Coder)
A type of voice coder. Usually
consisting of a speech analyzer and
a speech synthesizer which convert
analog speech into digital signals
for transmission and digital signals
back into artificial speech sounds for
reception.
