Thanks for the replies. Again a fresh thread because the original
is closed to further reply.

From: Jon Elson
Date: Mon, 19 Dec 2011 14:37:22 -0600
This may be a bad video cable. It could be reflections on the cable
bouncing back and creating the ghost. It could also be a failed
termination resistor in the monitor, or a bad contact or broken solder
joint at the video connector.

To test, I replaced the beige colored cable about 1.5 m long and
apparently original, with a black colored cable about 2 m long and
skinnier. No significant difference in the display. For sake of
interest, the black cable was still folded and fastened with a twist
tie and inside the thin polyethylene sleeve from shipping. In
hindsight, not an arrangement to ignore. After a couple of hours
this way, the cable was quite warm to the touch. Luckily I was
paying attention and changed back to the heavy beige cable.
I wouldn't have expected a video cable to generate that much heat.
The current is too large or the black cable has wire cross-sections
pared a minimum, or both.

From: Jeff Urban
Date: Wed, 21 Dec 2011 18:54:37 -0800 (PST)
... There is a way to do this on almost any CRT based monitor, but the
question is whether it is worth it or not. The focus isn't really all
that bad but it ain't that good either. ...
Without the print of the CRT socket board, ar at least a sheet on the
IC(s) on it, it's about impossible to do anything. In fact that's true
even if it's not an HK short.

So the practical conclusion is to replace this old monitor with a
flat
screen purchased for less than $100 from a local broker.

Thanks, ... Peter E.