Every time I have seen this PTO jumping problem (in my Argosies too) it
has always come down to the four circuit board to VFO shield box screws.
They provide the ground path for the VFO circuit and what I've seen is a
build up of very slight oxidation on the circuit board pads themselves.
I remove the four screws and carefully clean the board where it would
physically contact the chassis at those four points and then bolt it
back down. No more PTO jumping. This is not a difficult job but it would
take an evening. You have to get to the screws that hold the PTO
assembly in place... move the PTO assembly so that you can take off its
lower shield plate and then you have access to the four screws. This
work should not effect the PTO operation.... just don't go 'squirting'
cleaner all over the board.... just clean the spots where that board
makes physical contact with the PTO case.
73,
Jerry, KG6TT
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