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  #1  
Old 06-07-2009, 09:20 PM
sansui2000A sansui2000A is offline
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Progress is slow....I still have the arcing sound and reduced vertical and horizontal sweep. I can't see any arcing in a dark room, but I can hear it and see the raster flicker. I'm suspicious of the 600pf 30KV cap from the HV lead to ground. Has anyone seen one of these caps give problems (arcing)? It snaps into clips and has 1/8" diameter axial leads. It doesn't arc when the cap is removed.

Also, I felt a tingle when I touched the chassis and measured 70VAC from chassis to ground..any possible cause other than leakage from the power transformer?

Last edited by sansui2000A; 06-08-2009 at 08:43 AM.
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Old 06-07-2009, 09:35 PM
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jeyurkon jeyurkon is offline
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Quote:
Originally Posted by sansui2000A View Post
Progress is slow....I still have the arcing sound and reduced vertical and horizontal sweep. I can't any arcing in a dark room but I can hear it and see the raster flicker. I'm suspicious of the 600pf 30KV cap from the high lead to ground. Has anyone seen one of these caps give problems (arcing)? It snaps into clips and has 1/8" diameter axial leads. It doesn't arc when the cap is removed.

Also, I felt a tingle when I touched the chassis and measured 70VAC from chassis to ground..any possible cause other than leakage from the power transformer?
The line to chassis caps will do that also. You said you replaced them. What value did they have in it? You should also use a safety cap for the the line to chassis cap. JustRadios has an explanation on their site about which types to use.

Assuming it's a direct leak from a 120VAC line and that you measured it with a 10meg input impedance voltmeter then you have about 5 microamps of leakage current. Most GFCIs are set to trip at 5 milliamps. I think you're pretty safe and that what you're measuring is due to the line to chassis capacitor. Just make certain that it's the correct type of safety capacitor.

John
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Old 06-07-2009, 10:28 PM
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Eric H Eric H is offline
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Quote:
Originally Posted by sansui2000A View Post
Progress is slow....I still have the arcing sound and reduced vertical and horizontal sweep. I can't any arcing in a dark room but I can hear it and see the raster flicker. I'm suspicious of the 600pf 30KV cap from the high lead to ground. Has anyone seen one of these caps give problems (arcing)? It snaps into clips and has 1/8" diameter axial leads. It doesn't arc when the cap is removed.
Yes those "doorknob" caps can arc internally.

I found a bad one just last week, it made a constant crackling sound but I couldn't see anything arcing, I found it by subbing it with another.

It probably won't cause the reduced sweep.

Does this set have two 1B3 rectifiers in a doubler circuit?
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