Hi;
I'd almost bet this is another dried-up electrolytic, I just can't seem
to find it! The perpetrator is an HP 98751a, aka Sony GDM-1952, (aka
Rasterops 19, Supermac etc), and it is a 5-BNC RGB fixed-frequency
monitor that does 1024x768 INTERLACED only. Given that, it has been a
great display anyway and I'd hate to throw it out.

Problem started a few weeks ago at turn-on. The screen seemed to be
traced fully and normally by one field, while the other scrunched up
away from the bottom-- so that I had two mouse-pointers spaced about an
inch apart when at the lower half of the screen, but moving the mouse
up the screen, the pointer images melded back together. As the monitor
warmed, the scrunched field stretched back to normal over about 5
minutes. I operated it "as-is" a couple of weeks, just waiting for it
to settle out.

Well, it is worse now-- the whole lowest quarter of the screen is
affected, and no getting back to normal after even 30 minutes of
on-time. I downloaded a zip of .pcx files of the GDM-1952 Service
manual, which has the schemata but they neglected to scan in usual
boilerplate like Theory of Operation or anything. So I'm guessing what
I need to look for. But I am not seeing electrolytics in area which
might affect one field but not the other!

Has anyone else battled this symptom? Am I making stupid assumptions or
have I missed something? My current web method of posting does not
allow me to send a file along, but for those who already have access to
the schematics, I am suspicious of C1, C2, and C8 (in the
SyncSep/PulseGen section). My reasons for looking at these a 1) they
are electrolytic; and 2) they are roughly around an area that looks
like it might have something to say about one fields vertical as
opposed to anothers. But I may be all wet.

TIA-- Glynn.