17" RCA with doors

[sansui2000A]

Installed the first batch of caps...have to order more. One of the plastic covered paper "line to chassis" caps was split open. I heard the set of pop once before I started recapping, so that might of been it. It's amazing how much smaller the modern electrolytic capacitors are compared to the metal cans. Same goes for paper vs. polyester film.

[bandersen]

...amazing how much smaller the modern electrolytic capacitors are...

They sure are - more room for ventilation!

That's the main reason I don't bother re-stuffing very often. I just leave the old cans in place and stick the new ones underneath. I've been criticized for that (mainly by radio restorers)

Either way, we're preserving history

[sansui2000A]

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?

[jeyurkon]

Originally Posted by sansui2000A

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

[Eric H]

Originally Posted by sansui2000A

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?

[Tubejunke]

Where can you find "doorknob" caps at?

[sansui2000A]

It has a single 1B3. What is the best way to test the cap? Apply HV to it from another TV and see if it arcs? I used new safety caps from justradios

[jeyurkon]

Originally Posted by Tubejunke

Where can you find "doorknob" caps at?

Surplussales, ebay, rfparts...

John

[jeyurkon]

Originally Posted by sansui2000A

It has a single 1B3. What is the best way to test the cap? Apply HV to it from another TV and see if it arcs? I used new safety caps from justradios

It sounds like yours is arcing internally so the only indication that it's arcing, if you tried it on another set, would be it pulling the HV low on that set. I guess you'd hear the arcing.

John

[sansui2000A]

I found a doorknob cap one ebay, but It's coming from China so it might take awhile to get here. The cap in the TV is 600pf on the Sams the value is 500pf. The one I ordered is 500pf.

[Eric H]

Originally Posted by sansui2000A

I found a doorknob cap one ebay, but It's coming from China so it might take awhile to get here. The cap in the TV is 600pf on the Sams the value is 500pf. The one I ordered is 500pf.

Won't matter much you probably don't even need it if the CRT is Dag coated. It's just the HV filter.

[sansui2000A]

I tried the set without the HV cap and it seems to work fine with out it...no more sizzling


I replaced the Vert & Horiz. tubes along with some more caps and the cathode resistor on the horiz. tube. It measured 150 ohm instead of 100. I got a full raster for about 2 hours then the width shrank about an inch on each side.


The raster had a black bar in the center like hum on the video. It went away when I pulled the RF amp. from the tuner. The SAMs shows a 6CB6 as the rf amp, but the TV had a 6AG5 instead. Are they interchangeable?..any idea which one is correct?

Thanks

[jeyurkon]

Originally Posted by sansui2000A

I tried the set without the HV cap and it seems to work fine with out it...no more sizzling


I replaced the Vert & Horiz. tubes along with some more caps and the cathode resistor on the horiz. tube. It measured 150 ohm instead of 100. I got a full raster for about 2 hours then the width shrank about an inch on each side.


The raster had a black bar in the center like hum on the video. It went away when I pulled the RF amp. from the tuner. The SAMs shows a 6CB6 as the rf amp, but the TV had a 6AG5 instead. Are they interchangeable?..any idea which one is correct?

Thanks

They're similar, but not exactly the same. The 6AG5 has the supressor grid connected internally to the cathode. The 6CB6 doesn't. Does the Sams show pin 7 & 2 connected?

Is there a tube chart on the set?

John

[sansui2000A]

No tube chart, but the sams shows a 6CB6 symbol without the internal connection. I have a 6CB6 coming from ebay.