Motorola HT 1000, Руководство пользователя

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Radio Squelch Unmute/Mute This option defines the conditions for muting and unmuting audio.
The three choices are STD/STD, AND/OR, and AND/STD. The first term
(before the slash) refers to the unmuting conditions, and the second
term (after the slash) refers to the muting conditions.
Note: If Carrier Squelch is chosen, STD/STD unmuting/muting
will be forced. PL or DPL decode must be enabled to have AND
unmuting or OR muting.
Make sure you follow the following guidelines:
• Set up the PL/DPL configuration on the CHANNEL
CONFIGURATION screen ( F4/F4 ) before choosing a setting for this
field.
• To maximize coverage area, use STD/STD, but note that audio
quality will degrade further in “fringe” areas before the radio
ceases to unmute.
• To ensure reliable operation, use AND/OR, but note that “fringe”
area range will be slightly reduced. Performance in normal signal
strength areas will be identical.
Note: This field will be forced to STD/STD if Carrier Squelch Receive
has been chosen on this channel.
The default is AND/STD.
STD unmuting The receiving unit will unmute audio when PL/
DPL detect is true. This type of unmuting has also
been referred to as “Code” or “Squelch Code” in
other RSS packages.
Using STD unmute will cause the audio to unmute
at lower signal levels than AND unmuting. This
will allow the user to operate further into the
“fringe” areas, or through weak areas in the
coverage of the Repeater. In areas like these, the
audio may be noisy however.
STD muting The receiving unit will mute audio when PL/DPL
detect becomes false. STD muting, like STD
unmuting, allows operation further into the
“fringe” areas of the system.
AND unmuting The receiving unit will unmute audio when PL/
DPL detect AND carrier detect are both true. This
type of unmuting has also been referred to as
“Code and Squelch” in other RSS packages. AND
unmuting results in the most reliable operation,
minimizing squelch falsing (noise bursts) when PL
or DPL is being used. However, as mentioned
above, AND unmuting will result in a slightly
reduced coverage area.
OR muting The receiving unit will mute audio when either PL/
DPL detect OR carrier detect becomes false. OR
muting will cause the radio to mute audio sooner
than STD muting (smaller coverage area), but
results in more reliable operation (less squelch
falsing).