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hv sparking problem

I am working on a Toshiba 32hf72 chassis N2PS. Found a bad flyback and replaced it. Now there is a problem with the HV sparking. At first it sparked around the anode connector. I cleaned that with no effect. I have found a couple things that don't make sense to me:

Connected the HV to another tube and connecting the dag together with no other connections yield proper start up with no sparking. Connecting the tv together normally, but using a different yoke that is not on the tube makes the tv start up, but it sound wrong. there is a sound like sizzling inside the tube. Hard to describe. if the yoke on the tube is connected instead of the other yoke, I get sparking again. ANY ideas?

Reply to
calvinsff
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Bad CRT? Air in CRT?

Reply to
Ancient_Hacker

I dont know what specifically you cleaned, but I know that any arcing converts anything present to carbon, and any cleanup has to be very thorough indeed to work.

If youve replaced the EHT wire/rubber cap and cleaned everything immaculately, the only remaining culprit would be the CRT, if thats where the sound is coming from. Dont think I've encountered a tube doing that before, but if it is, it is.

NT

Reply to
meow2222

Power up the monitor while in the dark - you should then be able to locate where the arc is occurring from and work from there. If it's coming from where the cap meets the tube, try using RTV to seal the connection.

Reply to
JW

I cleaned the anode cap and the tube where it attaches. I experimented a little more and found that the sparking happens when the horizontal half of the yolk is connected, but using the horizontal section from another yolk, I get a dot in the middle of the screen, so the tube works at least a bit. Can I assume that if i get a dot, then the tube is fine or could there still be a problem with the tube?

could a problem > Ancient_Hacker wrote:

Reply to
calvinsff

definatly coming from under the cap. Is it possible the HV is WAY to high? if so and I manage to seal it, would this cause problems?

JW wrote:

Reply to
calvinsff

Of course it can do harm to you and the TV.

But first clean the area again and lift the rubber suction cap away from the tube so that any carbon tracks on it aren't an issue. See if it powers up without sparks.

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Reply to
Sam Goldwasser

These 2 paras appear to contradict each other, so I can only say I dont know whats happening. As you didnt replace the rubber cap and lead, really its hard to conclude much.

ABL? whats that?

NT

Reply to
meow2222

auto beam limiter.

snipped-for-privacy@care2.com wrote:

Reply to
calvinsff

no connection

NT

Reply to
meow2222

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