Kenwood TR-851A Instruction Manual page 28

4-7-7, Channel linkage
The channel linkage feature allows you to shift from
the present frequency to the first available open
channel! by a single touch of the button when there is
interference between communication channels.
When the CHL key is pressed, the following opera-
tions take place in sequence (This is called the Chan-
nel Linkage operation.):
Channel linkage operation
Start channe}
i . "Beep"
CHt key ON
Opan channel
Memory channel 7 145) 0. 25
2. esi e r hoe CHL light flastws
Open channel search
Start channel
oy
:
=
Control signal (Channel dati
- CHL bght flashes
is transmitted automatically.)
psene ie Y Opon channol
a
CHL light ON
Senes of dual beeps
4. '
Shift to open channel
1. The frequency displayed when the CHL key is
pressed is stored in memory as the start channel.
2. A search for an open channel begins.
3. The start channel is recalled. The data (Control
signal) including the open channel frequency
is transmitted (Requires approximately 0.2
seconds).
4. Control is passed to the open channel.
A channel linkage operation can begin from any fre-
quency within the band.
Open channel search range:
An open channel search operation will search up to
11 channels from the frequency stored in memory
channel 7. (A total of 12 channels). Store the start
frequency in channel 7.
Open channel search proceeds in steps according to
the table shown below.
TR-851A/851E 'TR-751A : TR-751E
| 25 kHz 1SkHz* | 25 KHz
28
Notes:
1. Scan will begin from the frequency stored in
Memory Channel 7 in the FM mode.
2. The frequency stored in Memory Channel 8 will
be skipped even if it is within the open channel
scan range.
3. 'Step size can be altered to 20 kHz if desired.
(See page 36.) (TR-751A only)
Open channel criteria
If squelch is closed (BUSY LED is OFF) for more than
1.5 seconds, the channel! is considered to be the
open channel.
A. Initiating channel linkage
(A} Simplex mode
1. Press the DCL key; the DCL light will go ON.
2. When no signal is received, adjust the SQL con-
trol until the BUSY indicator just goes OFF.
3. Press the CHL key. When the CHL key is press-
ed, the microprocessor performs the operations
1 through 4 in Fig. shown above, passing con-
trol to the open channel automatically. During
this operation, the CHL indicator flashes and
speaker output is muted. |
4. 3 beeps will sound and the CHL indicator is ON,
indicating that the channel linkage has been
completed.
5. Communicate with the distant station on the
new channel.
{B) Shifting to a simplex channel! from a repeater
When repeater operation has been selected +" or
o—er ("DA or ''D-B' with the TR-851E European
version) will be disptayed. Follow the steps below:
1. Press the DCL key; the DCL light goes ON.
2. When no signal is received, adjust the SQL con-
trol until the BUSY indicator just goes OFF.
3. Press the CHL key.
The microprocessor performs operations 1 and 2
in Fig. shown above to automatically search for
an open channel and then returns to the start
channel (the repeater channel). A series of 3
beeps will sound.
4. When the repeater becomes open, press the PTT
switch. About 1 second later, the control signal
will be transmitted to open code squelch on the
distant station.
5. Release the PTT switch. The control signal con-
taining the open channel information will then be
transmitted.
6. About 0.2 seconds after the control signal is
transmitted, the open channel will be selected
automatically. A series of 3 beeps will sound and
the CHL indicator will be displayed. Simuitane-
ously, the offset indicator goes OFF.
7. The radio is now on the open channel, in simplex
mode and ready for communication with the dis-
tant station.