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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 # 849
MODEL: TR-9000
SUBJECT: Transmitter Sideband Carrier Balance
                                                        
     Distorted sideband transmission may have one of two causes.
     
     If normal alignment does not cure the problem, distortion
     
     or poor carrier suppression may be improved by rerouting two
     
     leads in the wire harness
     
     PERFORM THESE INITIAL CHECKS FIRST:
     
    1. On early units, ascertain that R74, 47 ohm is present on the
         TX unit X56-1370-10 between connector 33, the LT line,
         and R27, 2.2K (vicinity of Q5, Q6), and that R27 is 2.2K.
         (Service Bulletin #824).
         
    2. Verify TR-9000 Service Manual alignments, General section
       steps 4 (PLL), and 5 (HET frequency alignment).
         
     3. TX section, steps #4 (power adjustment), 9 (SSB mic gain),
        10 (carrier point) & 11 (carrier suppression).
          
     PROCEDURE:
     
      1. Remove the bottom cover and unplug the speaker.
      
     2. With the radio upside down and facing forward, locate
          connectors 8 and 10 at the front of the RX unit X55-1260-00.
          Connector # 8, pin 3 (violet) is the -6V DC line from the
          TX unit, connector # 31, pin 1. Connector # 10, pins 7
          (signal) and 8 (ground) (green coaxial cable) is the MS
          pins 5 (sig) and 4 (gnd).
          
     3. Carefully cut the cable ties (without cutting any leads)
          securing these two lines in the wire harness which runs
          to the left, around the upright Control unit, and then
          right behind the front panel as far as the Mode switch.
          
     4. Carefully unplug each of these connectors by gripping
          the connector housing with a long-nosed plier.
          
     5. Extract the terminal from the housing by depressing the
          locking tab and simultaneously withdrawing the lead with
          terminal. (see illustration on page 2).
          
     6. Reroute these two lines from the behind the Mode switch,
          between the chassis and control unit, then left to their
          original connectors. Reinstall the terminals in their
          original positions in the connector housing.
          
     7. Coil the excess of each lead and secure with cable ties.
          Retie the harness behind the front panel, along the left
          of the chassis, and back behind the control unit.
          
     8. Readjust carrier suppression. Mod SW:USB, Mic terminal
        terminated with 470 ohm. On the RX unit, alternately adjust
        TC1 & VR6 for minimum output at 145MHz. Carrier should
        be at least -4OdB down.
   
     9. Work is complete. Replace the bottom cover.