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                             K E N W O O D
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                        Kenwood Service Centers

   Kenwood Service Corporation             Kenwood Service Center, East
   2201 East Dominguez Street              829 Lynnhaven Parkway, Suite 130
   Long Beach, California 90801            Virginia Beach, Virginia 23452
   Telephone 1-310-639-5300                Telephone 1-804-340-1702

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BULLETIN # 977
MODEL: TM-731A/TM-631A
SUBJECT: 2MTR FINAL UNIT FAILURE

We have seen several 144MHz Final boards in for service that have an 
RF burn in the area of L6 and C17. The combination of transmit current 
on the 8T line and SWR seems to be damaging C17. Once C17 is damaged, 
the circuit starts to burn. To prevent this condition, C17 will be replaced.

This modification has been incorporated in production from serial 
number 108XXXXX.

REQUIRED PART:		CK41FY1E102M


1. Disconnect the power supply and antenna.

2. Remove the top cover. Do not damage the speaker wires.

3. Remove the shield plate from the VHF Final unit.

4. Replaced C17 with the part listed above.

If you are servicing a TM-731A/631A that has already been damaged, the 
following items should be noted.

1. R11 is probably burned and needs to be replaced.

2. L6 may have "pin hole" burn marks through its insulation. If this is 
   the situation, L6 must be replaced or the circuit will burn in the future.

3. If the board has been burned, the carbon must be scraped off the board 
   to prevent the circuit from burning any further.

Time required to perform this modification is 1 hr. or less.