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the dead give away is the cold power resistors that stand up there are 3, on on the side of the board, two more center right. 27K wire wounds IIRC. look for crystalized solder around those. The whole pcb is subject to a lot of heat, esp around those 6GC7 tubes and the Video amp 12GH7 or 12BY7. just go easy working on it, those traces will lift. Also reflow the solder stakes that are used for ground if they look suspect at all. lastly check the blanker tube grid resistor to ground trace. Its right on the edge of the pcb that is near the horz out tube. that trace has been known to crack, causes a increase in the blanker tube neg voltage, the effect is two fold, a slightly darker pic (the neg voltage is used in the brightness circuit) AND on sets later than the CTC-12 its a HV hold down voltage that can upset the bias on the horz out tube (if the trace cracks open the HV and horz sweep will be reduced).
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