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#16
05-28-2012, 12:43 PM
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The service notes have a horizontal set up procedure using a basic scope. There is a test jack so you can do it from the top of the chassis.
"Bends" are usually caused by leaky sync coupling caps or shorted IF tubes. Check those first. 
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#17
10-11-2012, 12:52 PM
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Well,
I am back at working on the TV after a long break. Went to work on it las night and it looks like I have no HV, today i took the cage off, there is a large brown/black spot on the 6GB6 Horz output tube and when in operation I see what looks like HV inside the tube it has a slight blue ionized glow inside. So I am thinking that the tube is bad, I do not currently have a tube tester, as it was borrowed and I had to give it back. I also started gluing parts of the cabinet back together that where separating. Matt
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#19
10-11-2012, 03:41 PM
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Check the HV rectifier (1B3 I think) in the cage. The glow in the horizontal output, unless extreme is usually normal. Disconnect the plate cap with the set off, on the 1B3 and carefully position it away from everything, turn it back on and use a WELL INSULATED srewdriver placed near the cap to look for a arc to come from it. If you get the arc, the 1b3 has gone bad. For some reason I find HV rectifier tubes die shortly after they are returned to service. My T-933 Maggie and my Zenith N chassis both did that. Just be careful when using this test. No grounding the screwdriver and fingers on the far end of the handle.
No arc, check the negative voltage on the control grid of the horizontal output tube. Low or no voltage means no oscillator. Normal, check the 6BG6 and the damper. Does this set have a horizontal drive control?
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#20
10-20-2012, 02:12 PM
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Hi,
I checked and got no arc, the 1B3 is a post 68 RCA. When i measure the negative voltage on the grid it is -0.9 sam's says it should be -4. Yes it does have a drive trimmer. I am measuring with the fluke 28 FM in the DC range with the negative lead clipped to a spot on the chassis and the positive to the test point. Matt
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