Nortel Networks RTU-292 - Manual (Page 9)

RTU -292 Operations Manual
Glossary
Adaptation The process whereby the RTU-292 DSP algorithms detect reflected signal information in a
connected line and tune the DSP hybrid for a broadband null with minimum reflection.
COR Carrier Operated Relay - A receiver signal that gives a positive indication that a carrier or signal
is being received and that the receiver is unsquelched. Same as COS.
COS Carrier Operated Squelch - See COR.
CTCSS Continuous Tone Controlled Squelch System. A squelch system using EIA Standardized sub-
audible tones in the 67Hz to 250Hz frequency range. An FM squelch which opens only when
the proper sub-audible tone is present.
DIP Switch Dual In-Line Package Switch (Also “dipswitch”)- A multi-unit switch that fits into a standard
DIP integrated circuit footprint. It usually contains eight or ten individual switches.
DTMF Dual Tone Multi Frequency - The standard touch-tone telephone dialing method.
DSP Digital Signal Processing (or Processor).
EIA Electronic Industries Association.
Full Duplex A communications system that can operate in transmit mode and receive mode simultaneously,
with different frequencies for transmit and receive. See also Half Duplex and Simplex.
Half Duplex A communications system that uses different frequencies for transmit and receive operation, but
can not transmit and receive at the same time. See also Full Duplex and Simplex.
Hangtime A system with hangtime will remain in the transmit mode for the duration of the set hangtime
beyond the time indicated by any keying inputs. The hangtime prevents transmitter unkey
during brief pauses in the transmission.
Key To key a transmitter means to cause it to transmit.
LED Light Emitting Diode.
LMR Land Mobile Radio.
Mute To quiet or inhibit audio.
PCB Printed Circuit Board.
PTT Push-to-Talk. An active PTT signal causes a transmitter to key.
RX Receiver or Receiving.
Simplex A communications system that uses the same frequencies for both transmit and receive
operation. A simplex system can obviously not transmit and receive simultaneously. See also
Full Duplex and Half Duplex.
SNR Signal-to-Noise Ratio.
Squelch A means of detecting audio and causing some action when it is present, such as keying a
transmitter or unmuting an audio path.
TX Transmit or Transmitter.
VMR Voice Modulation Recognition. A type of squelch, which is activated only by spoken words and
not by tones, noise, or other audio information.
VOX Voice Operated Xmit (Transmit). A circuit or algorithm that causes a transmitter to key or some
other action when voice or other signal is present. This squelch type is activated by any audio
signal, and is not restricted to voice only.
JPS Communications, Inc. 9