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Old 08-01-2016, 08:48 PM
walterbeers walterbeers is offline
Old TVs are better!
 
Join Date: Jun 2011
Location: Omaha NE
Posts: 463
It was bound to happen, I had it on, when my friend Jamie "jstout" was over here, had an ok picture, ran it a while, looked back and all it had was a dim blur on the screen. Got back into it, and luckily the problem was minor. R173 a 1 watt 4.5 Meg resistor coming off of the HV adjustment had opened up, causing the 6BD4/6BK4 regulator tube to conduct real heavy causing the HV to drop way down to around 15KV. Luckily it didn't hurt the flyback or the tubes in the HV section. Getting my hands down into the HV cage was a challenge as I didn't want to pull the entire chassis again. I had to actually clip out the bad resistor, and I tacked the new one on the end terminal of the HV control, running a jumper wire to the other end, where the old resistor was. It's now working again. If I ever have to pull the chassis in the future though, I will put the resistor back into it's original place, but since it only has like 165 volts across it, a jumper wire sufficed. Actually the HV regulates much better than it did before, and doesn't pull in from the sides near as much with increases of brightness. Tried to touch up the convergence but I don't think I will ever get it perfect. It's close but wish I could get it better. In the photo of the HV section, you can see where the resistor was as I temporarily had red and yellow alligator clips clips on to where the resistor belongs.
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