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  #1  
Old 10-29-2010, 11:38 AM
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miniman82 miniman82 is offline
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Project VT-71 nearing completion!

I got tired of refinishing the cabinet for now, so I'm moving on to trying to figure out why the sync sep circuit is unstable. Set works pretty well, but it randomly looses sync at times.
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Last edited by miniman82; 04-15-2012 at 03:06 PM.
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  #2  
Old 10-29-2010, 03:50 PM
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Finish on that cabinet is dee-licious.
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  #3  
Old 10-29-2010, 08:05 PM
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bandersen bandersen is offline
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Lookin' good
Is it loosing horizontal or vertical sync ?
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  #4  
Old 10-29-2010, 09:39 PM
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It's bad horizontally, and the hold control is very sensitive. After it's been on for a little bit, it starts tearing horizontally and the hold control won't bring it back. There's still a few micamold caps in there, so I should probably get the remaining few.
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Old 10-29-2010, 09:55 PM
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Definitely replace the micamold paper caps masquerading as micas. If you do replace the two mica caps in the horizontal output (680pF & 900pF), make sure you use 1000v mica caps.
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  #6  
Old 10-30-2010, 09:40 AM
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I have a 560 @ 1kv I could use in place of the 680, but the closest thing I have to 900 would be .001uf @ 600vdc. How critical do you think those 2 caps are?
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Old 10-30-2010, 11:26 PM
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I think they're fairly critical, but you might as well give it a try. I used a 910 pF mica cap.
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