(no subject)

From: Phil Dibowitz <webmaster_at_ipom.com>
Date: Tue Dec 12 15:02:05 2000

> FWIW, I normally use an HV probe to discharge a CRT as well. It's a
> resistorr that I know will withstand the EHT, and by watching the meter I
> can tell when the CRT is discharged.

I lack a meter that works with my probe, but I held it on there for a good
10-15 seconds...

> If the heater is going on and off (and if the picture is OK when the
> heater is on), look for bad connections in the heater circuit first.

That's exactly what it's doing.

> Often the heater (in a TV) runs off a winding on the flyback transformer
> (the HV transformer that links to the rubber 'flower' on the CRT flare).
> Check for dry joints at the flyback transformer pins, dry joints on the
> CRT socket, dirty CRT pins, etc.

I don't know which pins that the instructions (or you) are talking about. I
checked all the wire connections... don't know about the joints... (sorry, I'm
new to repairing CRTs.

> This sounds like the 'getter'. It's a film of a reactive metal (barium, I
> think) that is evapourated onto the glass when the CRT is finally
> evacuated. Any residual oxygen in the CRT will react with the getter
> rather than damaging other parts of the CRT.

Umm. I think you may have misunderstood me. The litlte burn mark isnt' on the
CRT, it's on the (I think) heater -- the little clear glass tube on the back
fo the crt that glows when the TV is on... or well is supposed to glow, but
more comes on and off.

> But if you get a picture at all, the CRT is still holding a vacuum. And
> the heater is probably OK (they _can_ go intermittant, but it's rare)

Picture comes in and fades to black, comes in and fades to black

Insanity Palace of Metallica
Received on Tue Dec 12 2000 - 15:02:05 GMT

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