Re: Is my monitor really broken?



Dave wrote:
<haddon@xxxxxxxxx> wrote in message
news:1163306472.559937.289640@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

I recently acquired a Sun GDM-90w10 (rebadged Sony w900) 24" widescreen
crt. It is very old (manufactured Dec '97), but it was in remarkably
good condition and worked beautifully.


The extra "click" you heard was the AC main power relay being powered off.

I don't know why nobody has suggested it (I am NOT a repair professional,
feel free to correct me if I'm wrong) but if was a TV, you'd have a bunch of
posts telling you that some protection circuit had kicked in and that, given
the age of the unit, perhaps you'd be wise to check your electrolytic caps
in the power supply. Like a television, your monitor has a protection
circuit which monitors various voltages. If it detects either over or under
voltage (or DC voltage in some cases) it shuts down the unit to avoid
damage. There's a fair bit of heat generated inside these monitors, and
electrolytic caps DO dry out over time... If your SMPS voltages are all
okay, a shorted HOT would definitely give you similar symptoms.

If anybody has a schematic for you, it will save you countless hours.... but
I know Sun isn't that forthcoming with hardware manuals.

Dave




Some also have a shutdown that detects lack of deflection, most monitors have separate HV and horizontal circuits so if the horizontal deflection transistor is shorted, cold solder joints, etc the monitor will have similar symptoms.
.



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