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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 # 1024
MODEL: TS-950S/SD
SUBJECT: Transmit Spur                                        

Symptom:

A transmitter spur might be present at a dial frequency of XX.XX1 MHz.  This
spur is quite small but might become noticeable when the transceiver is used
with a linear amplifier.  

Cause:

The transmitted signal enters pin 5 of IC11 which is in the last PLL loop 
in the AF unit due to RF feedback.  This pin is the input for the 10 MHz 
Ref Osc signal from the CAR unit.  IC11 is the source of the spurrious 
signal since both the band and 10 MHz frequencies are divided by the 500 
kHz comparison frequency supplied by IC11.
 
Corrective Action:

To reduce this RF feedback increase the Ref Osc level from .2V to .7V rms by
adding the accompanying circuit to the input of IC11.  

Parts Required:

Qty     Description             Kenwood Part No.        Circuit Description
1       12 uH Ferri-inductor    L40-1201-17             NA
1       10 pF Chip Cap          CC73FCH1H100J           NA
1       16 pF Chip Cap          CC73FCH1H160J           NA



Caution: This modification requires soldering equipment rated for CMOS type
circuits.  It also requires familiarity with surface mount soldering
techniques.  If you do not have the proper equipment or knowledge do not
attempt this modification yourself.  Seek qualified assistance.

Time required for this modification is 30 minutes or less.
Service code A:56 B:X49-3020 C:ADDC  D:91

                                    (Add)
   10 Mhz Ref  <-------C107-------INDUCTOR-----------PIN 5
                               |             |       IC-11
                               |             |
                        (add) 10 pf         16pf (add)
                               |             |
                               |             |   
                              GND           GND