Kenwood TK-280 Service Manual page 7

● User selectable lockout
If the scan lockout feature is programmed to a key, the user
can lock systems out of the scan sequence with the key. To
lock a system out of the scan sequence, press the key when
the system is displayed. The Delete (3) indicator is displayed
on the left of the SYSTEM indicator.
To unlock a system, select the system and press the key.
The Delete (3) indicator disappears to indicate that the system
has returned to the scan sequence. The revert system is
scanned even if it is locked out. If there a locked system, the
Delete (3) indicator flashes during fixed scanning. If all systems
are locked out, the scan stops and only the revert system is
received.
3) Drop-out delay time (Scan resume time)
If a call is received during scan, the scan stops. The scan
resume time can be programmed as 0 to 300 seconds in one-
second increments. The default value is 3 seconds.
4) Dwell time
The dwell time is the time after transmission ends until the
scan resumes in scan mode. It can be set 0 to 300 seconds by
programming. The default value is 3 seconds.
5) System/Group revert
System/Group revert can be programmed for one of the
following;
● Last called revert
The system or group changes to the revert system or group
when a call is received with the system or group being scanned.
● Last used revert
If a system/group call is received during scanning and the
PTT button is pressed for transmission and response within
the drop out delay time, the system or group is assigned as
the new revert system or group.
● Selected revert
If the system/group was changed while scanning, the newly
selected system/group.
6) Scan message wait
The time for staying with the home repeater that receives a
signal during system scan and monitoring data messages can
be programmed. If there is no signal from the home repeater,
the system is scanned for about 50ms. If there is a signal,
three data messages are monitored. Normally, three data
messages are monitored for each system, and it can be
increased in multiples of three data messages per line to up to
eight lines.
If the repeater data message indicates that there is no call,
data monitoring is terminated and the home repeater of the
next system is scanned.
OPERATING FEATURES
7) Group scan operation
to the ID codes of the selected group, the ID codes of the
other groups that are permitted for group scan are decoded.
(The two fixed ID and block decode codes are always decoded.)
selectable group ID codes for which group scan is enabled,
the group display indicates the group number that the call came
in with. That group then becomes the new selected group.
Group scan resumes after the specified dropout delay time or
dwell time shared by the system scan elapses.
8) In Conventional system.
signalling, are scanned.
a group scan (including group scan during a system scan)
temporarily stops (receiving) in a group that does not have
priority, a look back is performed to the priority group. Look
back is performed according to the look back time A and B
settings. If a call is received on the priority group, reception
immediately switches to the priority group.
3-2. In Case of Conventional Format
1) Scan types
●
that can be selected with the group selector.
●
group.
2) Scan Start Condition
channels that can be scanned. The transceiver must be in
normal receive mode (PTT off).
the scan starts. The scan icon "SCN" lights and "-SCAN-" or
revert channel (programmable) is indicated on alphanumeric
display.
3) Scan Stop Condition
satisfied.
1 A carrier is detected, then signalling matches on channels
2 A carrier is detected on the channel for which receiving
4) Scan Channel Types
1 Priority channel is the most important channel for the scan,
Group scan can be programmed for each group. In addition
If, during group scanning, a call is received with one of the
If QT or DQT is set for the channel, the channels, including
In case of the priority group is set in conventional system, if
Single Group Scan
You can scan all valid (ADD) channels in the displayed group
Multiple Group Scan
You can scan all valid (ADD) channels in the all valid (ADD)
One or more non-priority channels must be added to all
When you activate the key programmed to the scan function,
The scan stops temporarily if the following conditions are
for which receive the signalling is set by the programming
software.
signalling is not set by the programming software or when
the monitor (signalling cancel) function is activated.
and always detects a signal during scan and when the scan
stops temporarily.
TK-280
7