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Complete success.
Found R728 had carbon tracked from what I suspect was an overvolt being it's a carbon film subjected to some 400-plus volts during the initial power on and that particular tube warming up rather quickly. My theory anyway. What I do know is there's a clear carbon burn going from end to end and being on the bottom I didn't see it right away, a carbon comp has since replaced it and the wiggles along with the nagging vertical issue are gone.
Picture quality? Absolutely stunning for 1970 and I've known this set for the past 56 years. Remaining issues? None. A couple of loose ends with the add-on MTS decoder I use in place of the sound discriminator and a mountain of cat hair that's trapped in the cooling fan is really all that remains. What a ride this has been!
So at this stage I'm going to run it for a while and construct the Phil Nelson CT-100 triode based video input adapter that uses the 12AT7 and go from there. It's not a need so much as I have the IF working quite well but now that all the variables have been worked out I can move to the next chapter.
Give me a day or two and I will post more pictures of actual operation and some of what I feed the set with.
Again want to thank everyone for all their help and support. A special thank you to damen and Danny S. for help with the IF board and tuner. Without you I would still be at square one.
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