Comnet LBI-38435B, Руководство по обслуживанию

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LBI-38435B
12
channels. The scan rate will be faster when fewer
channels are programmed into scan memory.
Scan operation will be determined by the following
conditions:
•
Priority 1, Priority 2, and Non-Priority
Programmed*
The Priority 1, Priority 2, and up to six (6)
remaining channels in an eight (8) channel radio
or fourteen (14) channels in a sixteen (16)
channel radio will be scanned. Once a carrier is
detected (or correct Channel Guard tone is
decoded), the digital display will indicate the
channel. Sampling of the Priority 1 and Priority
2 channels continues while receiving a message
on a non-priority channel. Should a Priority 1 or
Priority 2 channel carrier (and correct Channel
Guard) be detected while a non-priority channel
is being received, the applicable indicator (P1 or
P2) lights and the channel is switched to the
Priority 1 or 2 channel, regardless of what is
being received on the non-priority channel.
If a Priority 2 channel is detected, sampling of
the Priority 1 channel continues. Once a carrier
(and correct Channel Guard) is detected on the
Priority 1 channel, the channel is switched to the
Priority 1 channel regardless of what is being
received on another channel (Non-priority or
Priority 2). No sampling occurs during transmit
or if a Priority 1 channel is receiving.
•
Non-Priority Programmed: Up to eight/sixteen
(8/16) non-priority channels may be scanned.
Once a carrier is detected (or correct Channel
Guard tone is decoded), the digital display will
indicate the channel. Scan will stop and remain
on the channel until the carrier disappears, after a
few seconds scanning resumes. The channels
will be scanned in descending order.
*The rate the P1 and P2 channels are sampled
while listening to a non-priority channel depends
upon whether an RF carrier is present or not. If
no carrier is present on P1 or P2, the scan rate is
fast. If a carrier is detected but incorrect
Channel Guard is present, the rate slows
considerably. This prevents the non-priority
signal from being badly distorted by the larger
mute times needed to detect Channel Guard. If
Channel Guard is not programmed for P1 or P2,
the scan sampling rate remains fast.
Transmit In Scan Mode
Several characteristics in the transmit mode occur if
the radio has been placed in the scan mode of operation.
•
Radio is in scan mode but there is no carrier
activity to top the scan on any channel.
Removing the microphone from its hookswitch
will stop the scanning activity and the radio will
revert to the pre-scan selected channel.
Replacing the microphone will enable the scan
mode after a few seconds delay.
•
Radio is in scan mode and carrier activity on a
channel has caused scan to stop. Removing the
microphone from its hookswitch will keep that
channel selected. When push-to-talk (PTT) is
pressed on the microphone, the transmit channel
will be the displayed channel. The channel can
be changed during this time as needed, but will
be forgotten when scanning resumes. Placing
the microphone back on the hookswitch will
cause scan to resume, after a few seconds delay.
•
The Channel Guard decode is disabled whenever
the microphone is removed from its hookswitch.
•
During the scan mode, the MONITOR and
CHANNEL selection functions are disabled if
scan is not stopped on a channel.
TO PROGRAM SCAN CHANNELS AND
SELECT PRIORITY
The selection of scan channels and priority is front-
panel programmable using the SCAN switch in
conjunction with the ADD and DELETE switch.
Non-Priority
1. Confirm that radio is turned on (channel number
is lit). If not, press the POWER switch.
2. If SCAN indicator is lit, press and release the
SCAN switch to disable scan function.
3. Select desired channel using the ADD or
DELETE switch.
4. Press and hold SCAN switch, then press the
ADD switch once to add the channel to the scan
list. The “S” indicator light will light to indicate
that the channel is now in the scan program.
5. Release SCAN switch.
6. Repeat steps 2 through 5 for each channel (up to
8/16) to be added to the scan list.
Priority 2 (P2)**
1. Perform steps 1 through 3 of the Non-Priority
procedure.
NOTE