Bill, for a fixed offset:
One idea is to add a switch to allow you to shift the PTO 5 kHz either
way from its setting. You could do this without drilling any holes in
the radio to preserve its unmodified value. To do this, you use a two
position center off miniature toggle switch. Hook it up on an angle
bracket attached to an existing screw on the bottom of the radio. Use
flat computer cable and lead the cable into the radio where you switch
in a padding component to shift the frequency. The necessary components
either caps, VVC, or inductor, could be mounted on a little daughter
board near the PTO, and the toggle just switches DC to bring one part of
the added circuit on line or another. Without the schematic at hand, I
am doing some generalization here and hand wavying, but you should be
able to get schematic ideas from other rigs or ARRL Handbook projects
having an RIT.
-Stuart
K5KVH
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