I swapped the audio and HV 6Y6 tubes and the HV went from about 8.8 KV to 10.2KV. The audio has crackling noises so it's pretty clear that there is leakage in that 6Y6.
That helped the focus issue a bit. It's livable, but I think I may have a problem with supply ripple or ringing in the horizontal section. The vertical focus is quite good most everywhere now. But the horizontal is off. When I reduce the width to what it was with the 10MP4 the horizontal resolution improves. It's not just a magnification issue because the test pattern resolution improves.
Something else I meant to ask about; when I received this set the yoke was 5-10 degrees off axis. I thought it was just misadjusted, but after restoring the set that was the position it has to be in for the scan to be horizontal. It's unchanged between the 10MP4 and 12LP4.
Is it common for yokes to need to be adjusted this way? If not, what could cause it?
John
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