🚀 go-pugleaf

Terry Pinnell wrote:
> I've just noticed that circular objects become squashed inwards from
> the right, the closer they are to the right hand edge of my screen.
> Doesn't happen with top, left or bottom edges to any significant
> extent - just the right. Circle looks like a lemon. No magnetic fields
> in the vicinity. Degaussed anyway but made no difference.
>
> This is an HP p930 19" CRT monitor. Although a bit apprehensive about
> fiddling with its menu geometry options, I did play blindly with some
> of them, but so far in vain.
>
> Can anyone help me isolate and fix the problem please?

Someone in sci.electronics.repair may know how, but also read the FAQ
at www.repairfaq.org.  Some libraries have Sams Photofacts repair
manuals, on paper or online.

The monitor likely has a dying electrolytic capacitor in its
horizontal sweep circuit, but an adjustment should fix the picture
well enough for you (it has for me)  In older CRT monitors that's done
by turning the slug in a horizontal circuit coil, but newer monitors
handle it digitally, either though a hidden menu or with special
equipment (Samsung's was $600, Panasonic's was homemade for $10 and
required a program they sold for $3).  If HP won't tell you how to
bring up any service menu, try to find the actual manufacturer by
reading the UL registration number and looking it up at UL.com.  Some
manufacturers, like Envision (AOC) and CTX were very good about
providing technical information to anybody (Envision even sent out
free service manuals by e-mail), while others are paranoid about
consumers electrocuting themselves.

Don't work on the monitor itself unless you have electronics repair
experience, and realize that glass breakage can be much a risk as
electric shock, so do not set the monitor upright on a bed or sofa or
it will fall forward.  Instead set it with the screen on the bottom.
Read all the safety precautions in the RepairFaq first.