KENWOOD TM-721A REPEATER CROSS-BAND INFORMATION




MODIFICATION PROCEDURE


To operate the TM-721A in the repeater cross-band mode, chip resistor
R121 on the Control unit (X53-3130-XX) (B/3) must be removed. The
following modification will detail how to access the resistor.

1.   Disconnect the power supply and the antenna from the transceiver.

2.   Remove the top and bottom covers (12 screws). Do not damage the
     speaker wires when removing the top cover.

3.   Remove the silver colored screws from the front panel chassis (2
     on each side, 1 on top, and 1 on the bottom).

4.   Carefully pull the front panel away from the body of the
     transceiver (do not disconnect any cables).

5.   Locate chip resistor R121 on the Control unit inside the front
     panel. Unsolder and remove the resistor.

                                 NOTE

     Read the time-out timer paragraph before you perform step 6.

6.   Assemble the transceiver by reversing steps 1 - 4.




TIME-OUT TIMER


The TM-721A provides a built-in 3 minute time-out timer. This
automatically places the transceiver in the receive mode after 3
minutes of continuous transmit. This function can be defeated by
removing chip resistor R122 on the Control unit inside the front
panel.



OPERATING PROCEDURES


Repeater cross-band operation allows the TM-721A to receive on one
band and re-transmit the signal on the other band. An incoming signal
will automatically be switched to the sub-band. The TM-721A will then
retransmit the signal from the main band. Each band may contain offset
and sub-audible tone information (the optional TSU-6 is required for
decode). The encode and decode tones for a single band must be the
same. Of course, the encoder or decoder may be individually shut off by
using the [TONE] and [CTCSS] keys. In addition, each band may contain
a separate sub-audible tone.


                              PAGE 1 OF 2






1.   Select the first frequency in the main band. If required, select
     the offset.

2.   Select the tone if needed. Selecting a tone will not turn on the
     encode or decode functions. To turn on the encoder, press the
     TONE key (the [T] indicator will light in the main display). The
     decoder will be turned on in the next step.

3.   Press the BAND key to move the contents of the main display to
     the sub-display. The decoder can now be turned on by pressing the
     F key and then the CTCSS key (the [CTCSS] indicator will light in
     the sub-display).

4.   Now select the second frequency in the main band. Follow steps 1
     - 3 as needed to select the offset and tone information.

5.   Adjust the main and sub-band squelch controls to the threshold
     point. The TM-721A will transmit in the repeater cross-band mode
     if the squelch controls are set too low or a signal is received.


                                 NOTE

  The next two steps place the unit in the repeater cross-band mode.


6.   Press the F key.

7.   Press the A.B.C. key within 5 seconds of pressing the F key.
     Three dots will be lit in the main display. The unit will now
     operate as described previously.



 ___________________________________________________________________
/                                                                   \
|                                                                    |
|                                                                    |
|                                                                    |
|                                                                    |
|                                                                    |
|                                                        CONNECTOR   |
|                                                    _______________/
|                            CN 102                 /   ____________
|                    LITH    _______                |  |            |
|                    BATT   |       |               |  |            |
|               R121        |_______|               |  |            |
|               x           x R122                  |  |            |
\___----____________________________________________/  |____________|