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Old 06-27-2015, 02:50 AM
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Tubejunke Tubejunke is offline
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Location: Martinsville, VA
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I have one about the same, but most of my problems were related to the horizontal efficiency coil going floppy and high horizontal output tube cathode current which can fry the flyback. I also had to replace the 3AT2 HV rectifier socket and bypass the resistor underneath. On these topics since you wanted pointers; my studies on old color sets in general is that the current I mentioned should be observed on a meter in series with the cathode (all current is measured in series). Some people place a .47mfd 600VDC cap in parallel (across the two meter leads) when making this measurement I believe to filter out unwanted AC and get a true reading. I'm not the best at explaining that. I have done it with and without the cap and got the same results.

I personally would run the set on a Variac or some variable AC line source at a reduced voltage. Since you have already been powering the set, you wont have to start at really low voltages working your way up. The old electrolytics in the power supply and other places along with paper or film caps have already proven that they can take the punishment of full line voltage. Feel the filter cans and/or carefully feel the smaller caps. They should all be cool to the touch. The set produces heat of course so I don't mean cold, just not hot. If one is suspect, look and see if it is positioned right near a tube. That may be the reason it is hot.

We all need a good tube tester, so look on Ebay for a decent tube tester that can test the compactron style tubes in there. Don't buy just a basic emissions tester if you are really interested in this realm of electronics. Clean your tube sockets and pins. Trust me on that one. You have the best old color TV type that you could get as far as build quality and flybacks that last IMO and that of many others. Good luck and post those screen shots so some of these real wizards can put you in the right direction!
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