==============================================================================
                             K E N W O O D
   >>>   A M A T E U R   R A D I O   S E R V I C E   B U L L E T I N   <<<
==============================================================================

                        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

==============================================================================

BULLETIN # 56
MODEL: TS-180S
SUBJECT: DFC ERRATIC OR HUM
                                                        
     For complaints of either induced power supply hum, or intermittent
     frequency stability while using the DFC, perform the following
     changes to the VCO unit X50-1550-00:
     
        *1. Install a 330K ohm resistor between Qll G1 & the 8V line.
            Connect from L7 at C12 to Qll G1, at R35.
            
        *2. Replace L12 68uH with new part L40-6831-21.
        
        *3. Replace L13 150UH with new part L40-1541-27.
        
        *4. Install magnetic shield as illustrated. Use the two
            existing screws, plus double faced tape to prevent vibration.
            
        * New Part
        
     No adustments are necessary.
     
    Note: On page 37 of the Service Manual, the VCO Board view shows
           reversed callouts for Qll & Q15. D & S, and G1 & G2 are
           transposed.
           
                                                         
     This bulletin supercedes previous DFC bulletins 
     Please notate your Service Manual.