TMC Radio SRP 9100, Руководство по обслуживанию

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2 ~ SERVICE PHILOSOPHY
CLIM
Call Limit Time; time limit on calls made. Normally this is defined by the Call Time
Limit parameter but can by overridden by the TSC depending upon the setting of
TSCLIM.
CLIME Emergency Call Limit Timer.
Closed
A state where transmit and receive are not allowed until a Selcall message to open
the channel has been received. A Closed Channel is one that defaults (when
selected or after timed reset) to its closed state. Contrast with Open. Normally a
Closed channel would have Selcall Mute and PTT Inhibit would be enabled.
CODEC
COde (Analogue to Digital Converter) / DECode (Digital to Analogue Converter).
Community Repeater A communications set-up whereby different groups of radios can operate by using
only one base station. This is achieved by the use of CTCSS tone signalling such
that each group has a different CTCSS tone (encode and decode) and radios can
only communicate with other radios in their group. Only one group of radios can
use the base station at any one time.
Continuous A continuous control channel is one that is only used by one site. There are no
breaks in the transmission of signalling. Emergency Call Time Limit
Control Channel A channel used for the transmission of messages that enables the TSC to control
radios. Control channels may either Continuous or Timed Shared.
Control Channel Burst A feature that enables control channel burst transmissions on systems using time-
shared control channels. It is unavailable if the control channel acquisition type is
not 'Time Shared'. To make available: go to Control Channel Acquisition Type and
set to Time-shared.
CRU Central Repair Unit
CTCSS CTCSS stands for Continuous Tone Controlled Squelch System. A continuous
tone (lower than the audio range of the receiver) is modulated onto the carrier as
well as other signalling or voice traffic. Compare with DCS. Only receivers that
have been instructed to recognise the same CTCSS tone are able to receive the
transmissions, since the squelch of receivers looking for different CTCSS tones
prevents the audio from being heard. This provides a simple method of sending
messages to selected receivers only and allows several different networks to use
the same frequencies. CTCSS is also known as Tone Lock or Tone Squelch.
DAC Digital to Analogue Converter.
Dash (-) digits Digits known as 'No Tone' digits used in Selcall Identities.
DCS
Digital Coded Squelch system is based on sending a continuous stream of binary
code words using, low deviation, direct frequency shift keying. Only receivers
which have been instructed to recognise the same DCS sequence are able to
open their squelch and receive the associated speech transmissions. This
provides a simple method of sending messages to selected receivers only and
allows several different networks to use the same frequencies.
Decode Reception of signalling. Either Selcall where encoded tone frequencies are
decoded and identified as specific tones digits or CTCSS/DCS where tones are
analysed to see if the channel should be opened.
Demanded Demanded Registration; a procedure in which the TSC forces a single radio unit to
attempt registration immediately (providing the radio is not already attempting to
register).
Disabled The 'False' state of a parameter. That indicates this parameter is not active.
Typically this state is represented by an unmarked check box. Compare with
Enabled.