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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 # 1036
MODEL: TS-450S
SUBJECT: Parts Change

The 2SC2509 driver transistors are no longer available.  They have been
discontinued by the manufacturer.  A substitute transistor (2SC3133) is
available but requires some minor circuit changes  These changes are detailed
below.
 
Parts Required:
Qty     Description                Kenwood Part No.    Circuit Description
2       Driver Transistor          2SC3133             Q2, Q3
2       330 1W Carbon resistors    RC05GF2H331J        R8, R9
1      .047 uF Ceramic capacitor   C91-0119-05         C2
2       220 pF  Ceramic capacitor  CC45SL2H221J        C64,C65
1       560 pF Ceramic capacitor   CC45SL2H561J        C63

Procedure:

Make the following changes on the HF Final Unit (X45-3400-XX)

Change C2 to 0.047 uF. This is connected to the base of Q1
Change C63 to 560 pF. This is conneced to the Emitter of Q1
Change R8 and R9 to 330 0hm. These are connected to the collectors of Q2,Q3
Add 220 pF caps (C64,C65) from the collector to emitter of Q4 and Q5 

Note:   C64 and C65 should be soldered directly to the collector and emitter
        pins of the final Transistors Q4 and Q5.
                                        
Time required for this modification is 60 minutes or less.