[R-390] PTO endpoints

[Jim Brannigan]

It was a lot easier to pull the VFO, and attach a frequency counter.
I put pencil marks on the oldham coupler and PTO body as reference points.
wrote down the low frequency, counted ten turns, wrote down the high
frequency, count down ten turns, set to marks, adjust coil. Repeat and
adjust as necessary.
When I was done, I set the counter dial to the calculated PTO frequency and
reassembled.
Final calibration can be done with the "ZERO SET"

Jim

> I agree that adjusting the PTO endpoint trimmer coil is a pain in the neck
> using the manual procedure. There is an easier way to make the adjustment
> with the VFO in place and without removing the receiver front panel. (1)
> Remove the VFO subchassis. (2) Remove the screw cap covering the end point
> adjustment. (3) Reinstall the VFO subchassis. (4) With the entire receiver
> upside down on the bench, rest your longest, thinnest screwdriver against
the
> outer edge of the gearbox plate and poke it through the access port from
> which you removed the screw. (Don't even try to thread it through the
holes
> cut in the gearbox plates for this purpose.) It should just make it to the
> end of the slug screw. (5) Make the endpoint adjustment. (6) Remove the
VFO
> subchassis. (7) Replace the cap covering the end point adjustment access.
(8)
> Replace the VFO subassembly in the receiver. In making the adjustment I
use a
> 3/16" screwdriver 8" long sold by True Value Hardware under the Master
> Mechanic label bearing stock nos 127-399 TS322. (If you have exceptional
> dexterity -- or luck -- and some means of holding the plug onto the end of
> the screwdriver, it may be possible to remove and replace the cover plug
> while leaving the VFO subchassis in situ, thus eliminating steps 1, 3 6
and 8
> above.)
>
> Miles, K2CBY
>
>
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