Thanks for all the encouraging words of advice and consolation. I've heard from concerned friends all around the world in less than 24 hr. No less than a dozen by direct email, as well as some via the AMSAT-BB. This is an amazing team we have, isn't it. Honestly - Thank You All.
So, while not fully recovered - the prognosis is good for my trusty radio. Still in intensive care (with covers off), the major surgery went well. I first carefully pried off the shiny knob face, then gradually slipped a tiny screwdriver in under the knob rubber, moving around the dial - working it steadily off of the knob without stretching it. This revealed two holes, one of which gives access to the one set screw. Not the old-fashioned hex-hole requiring an Allen wrench, but a hex spline - my tool says "T-8".
Once the knob was off, I went ahead and removed the top and bottom covers so as to allow the front panel to hinge down revealing the inside of the encoder. I really didn't want to remove this, but needed to see that there was nothing inside that would be readily helpful. With the radio standing on it's back-side heat sink fins, face-up - I applied a few tiny tiny drops of WD40 with a tiny screwdriver, to the shaft where it enters the panel mount bushing (with the screw threads and big nut)... I turned the knob 360 degrees and applied a few more drops - and left it to penetrate for a while. Then came back and turned it and gave a few more tiny drops. I don't want WD40 inside the encoder if at all possible. If I don't take the shaft out of the bushing, I'll have to depend upon the WD40 and my incessant turning to eventually break down the dust or crud that had apparently gotten bolluxed into the juncture. I'll look at it as helping my friend thru a theraputic recovery process. Learning to tune again.
I repeated the process several times, and it got a little bit better each time. I had to go to work today, and there was no one home to do this every so often - so it may take a bit longer. It may be that by removing the encoder from the panel, I would see a better way, but I'll hope that my patience and persistence will pay off. It may never be as silky smooth as it was for the last 20 years, but I'm certain that it is on the road to recovery. While I wait for the WD40 to penetrate, I've been cleaning the face and knobs and buttons on my ol'buddy. It is truly amazing how nasty-dirty that stuff can get. Especially the buttons you DON'T push... Just a hint of WD40 on a Q-Tip can work wonders down in those grooves.
Such a long way from the first radio dial I ever re-strung. Can you believe that we used to do this with a spring-loaded string wrapped around a shaft, fed around pulleys, and tied to a wheel on the end of the shaft thru an air-variable capacitor ..?.. Uggh, and before that we had "crystals"...
I guess the WD40 is more of a rite-of-passage. Merely a mild stroke if you would. At least this time I didn't have to get out the duct-tape. Thanks again everyone who sat up late awaiting word from the recovery room. I think we're out of the woods as they say. At least I can see a clearing from here.
Thanks again and 73 for now /;^)