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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 # 938
MODEL: PS-430
SUBJECT: VOLTAGE INCREASE WITH TH-205/215

When the PS-430 is used as an external D.C. power supply for the 
TH205/215, the output voltage may increase to approximately 20V due to 
RF feedback. This condition is restricted to operating in the high 
power mode with the supplied helical antenna. Adding a by-pass capacitor 
between the base and emitter of Q2 on the AVR board of the PS-430 will 
correct this occurrence.

REQUIRED PART:

1000pF, 50V capacitor PART # CK45BlH102K

1. Remove power from the PS-430.

2. Remove the top cover of the power supply (10 screws).

3. Locate transistor Q2 on the upper left hand side of the AVR board 
   (X43-1440-00). The transistor and thermistor TH1 are covered with a 
   piece of shrink tubing to keep them in close contact with one another.

4. Remove the shrink tubing from Q2 and TH1.

5. Tack solder a 1000pF capacitor between the two outside leads of Q2 
   (base and emitter).

6. Reinstall the shrink tubing (if it no longer fits, just make sure that 
   the thermistor is in physical contact with the transistor).

7. Reinstall the top cover.


Time required for this modifications is 0.5 hours or less.