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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 # 918
MODEL: TS-940S
SUBJECT: SQUELCH SWITCHING NOISE

In some TS-940S below S/N 711xxxx, a "popping" or "clicking" noise may be 
heard when the squelch circuit is opened or closed. This may be more 
noticeable when an optional CW filter is installed. The following procedure 
will minimize the noise.

Parts required

	R194	 560K ohms 1/6W	                RD14CB2C564J
	R197     220 ohms 1/6W	                RD14BB2C221J
	R355,356 220K ohms 1/6W                 RD14BB2C224J
	C284	0.47 uF, 50V electrolytic	C90-0484-05

Procedure:

1. Disconnect the power cord and antenna from the transceiver.

2. Remove the top and bottom covers (16 screws).

3. Locate the I.F. board on the bottom of the transceiver.

4. Remove the 7 screws from the I.F. board.

5. Carefully unplug connector # 17 (right side of optional CW filter) 
   by prying up on the plug. Do not pull on the wires.

6. Move the 4 wires (yel, org, brn, red) that run across the far side 
   of the I.F. unit out of the way so the board may be removed.

7. Carefully lift and rotate the board toward the left side of the 
   transceiver to expose the foil side of the board.

8. Using a small craft knife, cut the foil at the 3 points shown in 
   figure 1 (top right corner of the board).

9. Unsolder and discard resistors R194 and R197. They are mounted on the 
   component side of the board and soldered on the foil side.

10. Install a 560K ohm resistor on the component side of the board
    as shown in figure 2. This resistor is now designated as R194

11. On the foil side of the board, add the 3 resistors (R197,355,356) 
    as shown in figure 3.

12. Add a small jumper wire as shown in figure 3.

13. Add capacitor C282 as shown in figure 3. Observe polarity and 
    insulate the positive (+) lead with shrink tubing.

14. Carefully place the board in its original position (do not pinch wires) 
    and secure it with the 7 screws.

15. Plug in connector # 17. Move the 4 wires on the far side of the 
    board back to their original position.

16. Put the covers back on the TS-940S and secure them with the 16 
    case screws.

17. Connect the antenna and power cord then test the transceiver for 
    normal operation.

This is an optional change that may not be performed under warranty.
Time required for this modification is 1.0 hrs or less.