Intermittent Shift In Display And Operating Frequency - Kenwood TS-830 Survival Manual

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had the rig open. A hint from another ham sent me looking in that direction. Replaced 2 or 3 and
that was the end of it. (Dale W4OP)
4. Check the external VFO DIN jack in the rear. Actually you will need to check it from the
inside. If you have one, put the matching DIN plug into the jack and pull it in and out several
times. This is a common problem with the 830. This jack has a contact which is shorted
WITHOUT an external VFO. If the contacts get dirty, it will do exactly as you described. You
might also want to spray a small amount of contact/electronic solvent on the jack and do the
plug in and out. (Brian KJ5AG)
5. I had what sounds like the same problem with a TS-830S. Turned out the FIX switch labeled
was intermittent. It is in the path of the voltage to the VFO and if it has some extra resistance,
the frequency would change. I tried "Deoxit" and that worked for a while but finally I jumpered
around the switch contact since I never used crystals for operating. Try operating the switch
many times and see if goes away for a while. (Dennis NT0V)
6. Maybe one of the xtal trimmer caps is going bad. The center pivot point is getting rusty.
Contact cleaner will fix this for a month or so but you need a new one.
6.6

Intermittent shift in display and operating frequency

(Author: Trio-Kenwood Communication, Inc.: "TS-830 frequency shift")
Some users may report an intermittent shift in the display and operating frequency. This may
typically be a 1 to 4 KHz random shift. Cause will be a loose grounding screw on the AF/AVR
unit heat sink.
On the AF/AVR unit X49-1140-00, there are three self-tapping screws holding the aluminum
heat sink to the PCB. These also supply the ground connection to that section of the board.
Between the heat sink and PCB foil, add a tooth-lock washer N17-1030-41 at the two self-
tapping screws on the side of the heatsink that has the two transistors attached. (The remaining
screw already has a lock washer.)
When replacing the board to the chassis, add a solder lug E23-0420-05 to the heat sink
mounting screw as shown, and tighten all screws for this board. Solder an insulated lead
between the TPG (Test Point Ground) wrap post adjacent to C81, and the added solder lug.
Procedure:
1. Remove the top cover (8 screws) and unplug the speaker.
2. Remove the bottom cover (8 screws).
3. Remove 5 screws holding the AF/AVR unit and swing the board over. Leads do not have to
be unplugged.
4. Add two tooth-lock washer as shown.
5. Replace the circuit board and heat sink to the chassis, adding the solder lug as shown.
6. Solder a jumper between the TPG wrap post and the added solder lug.
7. Replace the top and bottom covers.