User's Manual

ASTRO XTL 1500 Digital Mobile Radio with Control Head 27
Common Radio Features
Conventional Squelch Options
The term “squelch” is used to describe the muting of audio circuits
when signal levels received by a radio fall below a pre-determined
threshold. With carrier squelch, you hear all channel activity that
exceeds the radio’s preset squelch level. This squelch level is
programmed by your system manager.
Analog Squelch Options
Tone Private-Line (PL), Digital Private-Line (DPL), and network ID are
coded squelch modes; carrier squelch is not. Your system manager
can program each mode with one of these squelch options as
appropriate.
During carrier squelch operation, all traffic on the channel is heard.
During PL or DPL operation, your radio responds to only those
messages intended specifically for you.
Digital Squelch Options
Each conventional personality can be programmed for one of the
following squelch options in digital mode:
• Digital Carrier-Operated Squelch (DOS) —
This option allows you
to hear all digital traffic.
• Normal Squelch — This option allows you to hear any digital traffic
that has the correct network access code.
• Selective Squelch — This option allows you to hear any digital traffic
that has the correct network access code and the correct talkgroup.
• Data Squelch — This option allows you to hear any digital traffic that
matches the network access code and sel call packet.
96C67_Text.book Page 27 Thursday, March 1, 2007 8:54 AM