[comp.sys.sun] Sun monitor woes

mccaughe@turing.cs.rpi.edu (Eric McCaughrin) (10/08/90)

My Sun 2 monochrome monitor is starting to become flaky. Given the number
of flyback transformers that have failed in Sun monitors, I'm wondering if
mine is having the same problems. Maybe by describing the symptoms,
someone can confirm if the flyback transformer is the problem and I can go
ahead and order the advertised kit to replace it. Or perhaps someone knows
if it is something else.

It is a bit hard to describe what's happening, but here's a shot: Suppose
you start X windows with the default grey background pattern and nothing
else. When that's the case, everything is fine. Now add some xterms (white
background) with little or no text inside. Things are still OK except the
top and bottom of a window cause a ripple effect that spans horizontally
all the way across the window. As more and more text fills the windows,
the text becomes more wavy and the window edges are very wavy. Things are
really bad if, for example, you have a dark window on a mostly white
background. It seems that black-to-white and white-to- black transitions
cause the distortion.

The second symptom is that the right margin (between the edge of the image
and the edge of the monitor) is getting larger. At least that's what it
seems since it is now almost twice as big as the left margin. I don't know
if this problem is related to the waviness.

My gut feeling is that the right deflector plate voltage is not as high as
it should. However, I don't want to open the monitor and start playing
with adjustments because I don't want to screw things up. However, if
anyone has any expertise that they can lend, please let me know.

Eric McCaughrin
mccaughe@cs.rpi.edu
(518) 272-6197