Tait TB7100, Installation And Operation Manual

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TB7100 Installation and Operation Manual Glossary 131
© Tait Electronics Limited December 2005
city squelch
When a radio’s noise mute threshold is programmed for city squelch, the
radio is less sensitive to interference than if programmed for country squelch
and so stronger signals are required for the radio’s speaker to unmute.
City squelch is also known as local squelch.
CODEC
An IC which combines analog-to-digital conversion (coding) and digital-
to-analog conversion (decoding).
configuration file
A configuration file consists of all the configuration settings needed for a
base station, stored as a file in the configurations folder. Configuration files
have the extension *.t7p. The TB7100 uses two files, one for the receiver
and one for the transmitter.
country squelch
When a radio’s squelch threshold is programmed for country squelch, the
radio is more sensitive than if programmed for city squelch and so the radio’s
speaker unmutes more readily. When programmed for country squelch, the
radio can be used in areas where the signal may be weak and where
maximum range is desirable.
Country squelch is also known as distant squelch.
CTCSS
CTCSS (continuous tone controlled squelch system), also known as PL
(private line), is a type of signalling that uses subaudible tones to segregate
groups of users.
CTCSS/DCS filter
The CTCSS/DCS filter removes any CTCSS or DCS tones that may be
present on the received audio. The filter limits the range of frequencies the
radio passes from the incoming signal to the speaker and so in some
situations affects signal quality. Filtering can be automatically switched off
for channels that do not have CTCSS or DCS.
CTU
A Calibration Test Unit (CTU) is a device used to assist in making testing
and calibration of the TB7100 easier.
CWID CWID (Continuous Wave IDentification) is a method of automatically
identifying the base station using a Morse code.
D
DAC
Digital-to-Analog Converter. A device for converting a digital signal to an
analog signal that represents the same information.
data call
A data call is a call or part of a call between two radio units that carries data
rather than speech communications. A data call can be a status message,
short data message or non-prescribed data (NPD) call.
DCS
DCS (digital coded squelch), also known as DPL (digital private line), is a
type of subaudible signalling used for segregating groups of users. DCS
codes are identified by a three-digit octal number, which forms part of the