[R-390] Fix for ZERO ADJ.

[Andy G8JAC]

I just had to do mine.   The "stop" you feel is a flange on the inside of
the knob contacting a lug held by the nut that holds the assembly to the
front panel. The plate that you see is a pusher plate that operates the
clutch which is behind the large gear.

The adjustment is detailed in the TM but I don't think that it was
reproduced in the Y2K manual.  
Remove the knob from the Zero control.
Wind in the shaft until you feel the plate on the end contact the clutch
pins, then back off to give about 1/8 inch free play.
Re-attach the knob in a position so that turning it anti-clockwise nearly
hits the stop.
Turning Clockwise should now release the clutch (so that you can move the
VFO without moving the Veeder-Root counter). You may have to juggle the
position of the knob on the shaft to obtain a good positive clutch release
as the knob hits the stop lug.

Actually, I found that doing all this still didn't give me a good clutch
release so the only solution was to drop the front panel down so as to see
what was happening.
The culprit was the disk on the end of the Zero adjust shaft was so loose
that it was tipping over so that it failed to give even pressure on all
three clutch pins so the clutch didn't disengage cleanly.
The solution was to remove the shaft and disk and peen the end over so as to
stop the disk wobbling.  Re-assemble, adjust as above, problem fixed.
If yours is too far gone or broken, Fair Radio have them at $20.

Andy  G8JAC 



Has there been anything written about repair of the ZERO ADJ., when it does
not seem to release the clutch to zero the kHZ dial setting.  I am off from
1 to 3 kHZ over the full range of 0 to 32 MHz which is probably more than
just the zero adjust but I cannot do even the basic adjustment on any
calibration point from top to bottom.  Looking down inside the front panel,
I can see shaft turning and as it gets close to the stop point turning
clockwise, I can see what I assume is the clutch plate just barely moving.
I have looked through many of the instruction manuals I have but seen
nothing about repairing the ZERO ADJ.  I am guessing that someone out there
has repaired this at some point.


Ken Perales