Re: Intermittent fault in Eizo 19" T766 CRT

On Saturday 26 April 2008 13:21, bz wrote:

Sounds like you might have an intermittent short to ground on a power
supply line, perhaps inside a bad capacitor.
Or an intermittent connection in the voltage sensing circuits, or the AC
line into the power supply.

The problem here is, that I'm not too familiar with CRT screen electronics. I'm
pretty well versed in audio electronics and other more common, low voltage,
stuff, but I've never really had to deal with CRTs, so I don't know too much
about them, or how to localize the circuits you mentioned (except perhaps the
PSU).

Would you happen to know of a good book/guide about CRT repair, or at least an
explanation of the insides?


Intermittents are difficult to localize and fix.

Tell me about it... This fault only happens when it's just turned on, thus far,
and very hard to reproduce.


Perhaps you can narrow down the problem by monitoring voltages at various
points while it is acting up.

I also have a transient recorder, although only a single channel. Still, it
should be useful. However, come to think of it, the voltages inside the
monitor are probably too high for it...

.

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