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  #76  
Old 02-25-2019, 04:37 PM
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timmy timmy is offline
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Some of the crazy things they did back in the day would be illegal today, lol. Or UL wouldn't pass them as safe.
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  #77  
Old 02-26-2019, 01:54 PM
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bandersen bandersen is offline
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Quote:
Originally Posted by Zsuttle View Post
Oh, ok, nevermind then, I wasn't sure because I had measured line voltage from chassis to wall ground. Any reason for that?
The chassis is floating. Neither side of the AC line connects directly to it. One side does via a 470K resistor in parallel with a 0.05 uF cap if memory serves. I believe that is to provide a return path for RF.
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  #78  
Old 02-26-2019, 04:41 PM
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timmy timmy is offline
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Yes it is the RF return path but even though there is a.05 and 470k resistor, depending on what you may touch and the chassis there would be shock though, it has happened to me, not shocking, lol lol. I myself did measure line voltage from chassis to other areas of the set.

Last edited by timmy; 02-26-2019 at 04:54 PM.
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  #79  
Old 01-30-2020, 02:47 PM
koviatt koviatt is offline
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Quote:
Originally Posted by Zsuttle View Post
It could be, the when the contrast is all of the way up, the picture goes out of control. I'll replace the three that are there. EDIT: I was able to successfully get the picture back to normal by replacing the three capacitors around the contrast control. However, the slight shudder is still there along with the uncontrollableness created by turning the contrast or brightness to full.



Not entirely sure what to look for, however, here's the output of the plate on the sync. Hopefully that helps.

Attachment 198290


I've also purchased a TV analyst for troubleshooting, seems like a useful tool. WOn't be here for another week
Does this screenshot of the manual help? I had the same problem with my set and discovered that I replaced the cap that parallels the primary side of that transformer with a higher value and it filtered out the horizontal sync pulse to almost nothing.
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