Kenwood TKR-740 Service Manual page 11

fixed channel or a selected channel. When Priority channel
is set, Priority channel and non Priority channel is scanned
by turns. When scanning stops on the non Priority channel,
calls from the Priority channel is still checked at set intervals
while scanning is stopped. This operation is called Look Back
and the interval period is selected by the Look Back Time
function.
9.3 Revert Channel
The Revert channel is a channel that used to transmit during
scanning. The time from the end of transmission on Revert
channel to the time scanning automatically resumes is set in
Dwell Time function. The Revert channel types are Last Called,
Last Used, Selected + Talkback, Priority, Priority plus Talkback,
and Selected.
1) Last Called : The TKR-740 reverts to the channel upon which
a call was last received even if scanning has resumed (power
on default = selected channel).
2) Last Used (with Talkback) : The TKR-740 reverts to the
channel that was last transmitted on (power on default =
selected channel). However, if a call is received on a channel
other than the last transmit channel and PTT is pressed
before scanning resumes, the transceiver "talks back" on
the current receive channel.
3) Selected+Talkback : The TKR-740 reverts to the channel
set by the Channel 'X' functions or Channel Select function
prior to scan initiation. However, if a call is received on a
channel other than the selected channel and PTT is pressed
before scanning resumes, the transceiver "talks back" on
the current receive channel.
4) Priority : The TKR-740 always reverts to the Priority channel.
5) Priority+Talkback : The TKR-740 always reverts to the Priority
channel. However, if a call is received on a channel other
than the Priority channel and PTT is pressed before scanning
resumes, the transceiver "talks back" on the current receive
channel.
6) Selected : The transceiver reverts to the channel set by the
function prior to scan initiation.
10. CW ID and M essage
The TKR-740 contains internal automatic station identifiers.
The CW ID (Morse code) is set and transmitted on a per-
channel basis. The CW ID is transmitted when the interval
period is reached (TX Interval Time function), the channel is
changed (CW ID on Channel Change function) or CW ID On
function is executed. When CW ID is activated by any functions
described above, it is actually sent after the total time of TX
Delay Time (not applied to CW ID On function) and CW
Modulation Delay Time has expired. TX Delay Time is a period
from CW ID is activated to the transmitter is keyed. CW
Modulation Delay is a period from the transmitter is keyed to
the CW ID tone is sent. The CW ID tone is routed to the
Remote Receive Audio (Remote RA) port if the Send CW ID
to Remote RA function is set to Yes, consequently the console
can monitor the CW ID tone.
OPERATING FEATURES
CW Message 1 to 8 is transmitted on the current channel when
the CW Message 1 to 8 On function is activated, respectively.
11. PTT Priority
740 to transmit. The transmit audio path is switched according
to their keying souces and when PTTs is simultaneously
activated, the transmit audio path related to the PTT with higher
priority is given priority. These are Local Mic PTT, External
PTT, Remote PTT, Repeat PTT and Digital Pager PTT. However,
since Digital Pager PTT is considered lowest of priority, it is
not selected in the order of priority.
12. Intercom Operation
communication between the dispatcher at the remote site and
the servicing technician at the repeater. To use this feature,
Intercom On/Off (mandatory), TX Disable/Enable, Local TX
Disable/Enable and Remote TX Disable/Enable functions must
be optionally assigned to a PF Key or an Aux Input.
activated, a intercom operation becomes valid and a transmitter
is also keyed. To use the Intercom without keying the
transmitter, enable the TX Disable function (PF Key or Aux Input).
To use the Intercom with a local mic' s PTT without keying the
transmitter, enable the Local TX Disable function. To use the
Intercom with the wireline remote site' s PTT without keying
the transmitter, enable the Remote TX Disable function.
by the Intercom Remote/Local function.
1) Remote : Audio from the Remote TA port will be heard on
2) Local : Audio from the local Mic will be routed to the
3) Remote/Local : Audio from the remote and the local Mic
13. Voting Pilot Tone
Generator to be used with a voting comparator shelf. The
Voting Pilot Tone is sent from a remote receiver to a voting
comparator during idle periods. This continuous tone is used
to confirm that the phone line is intact as well as establish a
reference amplitude for the audio which will be present once
the remote receiver is unsquelched by a received signal. The
Voting Pilot Tone is a single-frequency sine wave and is turned
On and Off by toggling Voting Tone On/Off functions. When
any Voting Pilot Tone is selected, the selected Voting Pilot
Tone is automatically output to RA and Remote RA ports.
The TKR-740 contains 8 message banks for CW Message.
A number of keying sources can be used to cause the TKR-
The repeater has an Intercom feature which allows wireline
When Intercom On function is executed and a PTT is
The audio routing during Intercom operation is determined
the local speaker while a Remote PTT is pressed,
regardless of whether receiver audio is present.
Remote RA port on the rear panel regardless of
whether receiver audio is present. This local Mic
audio will be heard at the remote.
audio will be heard from the local speaker
and from the remote respectively,
regardless of whether receiver audio is
present.
The TKR-740 contains an internal Voting Pilot Tone
TKR-740
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