This sounds like problems in the CRT bias circuits, or in the HV multiplier.
The multiplier on most monitors is located on the side of the HV transformer
(flyback).

You must first check the biases to the CRT, and verify if they are in specs.
This may be difficult to determine without the service manual. The G2
(screen bias) to the CRT, and also the high voltage are important to verify.

--

Jerry G.
======

"Ger" wrote in message
...
Hi Group,
My PC Monitor is a DELL Multiscan P991. About 2/3 years old. Just about
useable in its present condition.
It suffers from the following symptoms:

1. Screen is overly bright even after using brightness controls. Contrast
is poor.
2. Icons are just a bit fuzzy
3. The 'flyback' lines are visible always

I have some electronics experience so taking the back off the monitor is
no big problem. I know about the hi voltages etc etc.
I am hoping that the above symptoms will be instantly recognisable by an
expert as either some internal adjustment I can make or some component
starting to fail and needing replacement.
Any comments or advice would be very welcome please.

Ger