CTC-53 vertical sync
 

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I have a pile of them but only one clean one that is in the TV room. Very poor vertical sync. I have totally recapped the circuit and installed numerous NOS tubes but I still have to adjust it occasionally as it warms up. They didn't always do this-I had one in the early 90s that had its share of problems but I don't recall vertical mischief being one of them.

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I was never impressed with vertical circuit on RCA's. How sensitive is it to adjustment of the vertical height and linearity controls? Almost every RCA set, including a solid state ctc-40 Ive worked on are very tempermental to adjustment of these controls. Slight adjustment and vertical sync is lost. Readjust the vertical hold to lock, try to adjust the size and lin controls and it slips out of sync again. I too have checked caps, out of tolerance resistors and cant get them to work quite right. Seeing that this exact same thing happens on a CTC-40, I know its not just to blame on tube circuit design.

Curious if any of you have experienced the same thing.

Zeniths are great, you can center the vertical hold control, and move it 1/4 turn either way and its still locked in solid.

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