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I appreciate the info about the (possibly fake) mica caps. I have finished replacing the paper caps in my CTC-5, and am just about to do the 'lytics, thinking I would be done.
Bryan, Television Engineering by Fink has an evaluation of this circuit but unfortunately no clues on how to adjust it or what the waveforms should be. It does say that this circuit has disadvantages of being sensitive to the signal level input - and is also sensitive to component values.
I think you should not see such interaction with contrast and other settings. So, I would trace the signal levels with a scope to see if there is a weak stage.
(Following comments refer to the super chassis, but I believe the deluxe is the same except for adding a noise gate stage.) Since you have SAMS, you could trace the signal levels with your scope, starting by setting the AGC for the correct video level (W1, grid of the video amp), then check waveforms for AGC keyer, sync separator and sync amp. These stages should have enough gain that the horizontal circuit is getting constant amplitude pulses with slight changes in AGC setting and any setting of brightness and contrast. You should have clean pulses like W7 shows at the input to the sync amp.
Good luck, and let us know what you find, because after reading the posted info, I have a feeling I may be doing the same thing soon!
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