https://drive.google.com/file/d/1bcH...ew?usp=sharing
This set has come a long way to get a picture. My video source is an RCA selectavision. Not the greatest in stability but its what I have in that room until my B&K 1077B comes later this week. So many ceramic and mica caps were bad. Also a bunch of resistors were off. I still think I have a heat related resistor going out of tolerance as the contrast looks great right after it powers up but within a couple minutes it starts to get way too bright in the dark areas.
Width is not working, but thanks to Phil Nelson's restoration there is a mica cap I have on order to replace the one in the High voltage box. Horizontal drive is off and I'm hoping that will be corrected by fixing that width and also a couple more ceramic caps in the Horizontal output section. The tube is ever so slightly red plating with a 1/4 turn on the drive control. At its minimum the tube red plates..... So I still think the HOT is drawing way too much current...
And my brightness cannot be dimmed. In the picture I sent in the link that is pretty much the dimmest it goes. Now that I know the circuits a bit more I see that the HV boost supplies the B+ that goes through the focus coil to the audio amp section as well as the cathode of the CRT. So if the width and drive are off I'm thinking that the boost is out of whack and there is too much B+ in that bus. Also the focus coil is near the lowest it goes to get good focus... All of that points to the HOT and damper circuits.
This set has been the most challenging and fun Tv's I've worked on. I can't wait to finish the last few remaining items!
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Matt Davala