Just to make a comment, this is one big long description! And, it is
well written. Have you thought of taking up literature, at the
professional level?

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This is not the type of fault that can be analysed over an email. The
fault would only be able to be found by verifying voltages, and
observing for the proper waveforms or looking for noise in the supplies
to the various circuits.

From the way you are describing the fault, this can be from noise due
to open bypass capacitors, or there may be some arching in a component
somewhere.

There is no way to accuratly tell you an exact fix. This is where a
properly trained skilled technician, who has the proper diagnostics
equipment, would have to work on the monitor.

One big problem with the computer monitors, is that the manufactures
will not sell service parts, or schematic diagrams to non-authorised
factory service techs.

If you call Hitachi, and ask about who is servicing their computer
monitors, I am sure that they will recomend where to bring it.

If the monitor is about or more than 5 years of age, I would strongly
recomend that you start shopping for a new one. I would not put a lot
of money in to an old CRT monitor. These can be now purchased at a very
low price in relation to the cost of servicing them.

Jerry G.
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