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Picked up some NOS RCA 6GH8 tubes, replaced several in the set IIRC sync sep, pincushion,chroma amp, and 1st video. This cleared up a nagging sync issue and gives a good clean pic with excellent contrast control.
I also replaced a weak testing RF amp tube 6HQ5 on the tuner and cleaned the tuner. The tuner acted like it was dirty but it was not that bad. The new tube needed to be wiggled to get it to work. Maybe something in the tuner socket, I hope not as I don't want to go there. Anyway after the clean/new tube/wiggle the tuner is working much better.
The pincushion correction phasing works well, but the top still seems to have more bow in than the bottom which is completely straight. will have to look over the circuit and see if I can understand how it works. It uses a tube like the zeniths which inverts the signal for either the top or bottom, and I think just uses cap for the non inverted correction.
I am thinking maybe a screen resistor may have gotten toasted when if a tube shorted (common issue with 6GH8). I dont remember seeing any thing that odd when checking the resistance chart. Maybe just the way it is, would not even notice it with out a cross hatch or letter box programming.
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