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No screen adjustment?

I have a Dell UltraScan P991 (AKA Sony) monitor that exibits excessive
screen briteness and retrace lines. Opening it up and there is no pot
adjustment for screen
or G2 on the flyback or anywhere else I see. Is this adjusted with DAS
only?
If so, is there a workaround so I can adjust the screen voltage?
Any and all constructive comments welcome. Thanks!
 
D

David

Jan 1, 1970
0
Adjusted with DAS only, there is no workaround. Troubleshoot the fault for
standard bright with retrace first and rule out all other possibilities. It
is poossible the video output ic has failed, or the video b+ is low.

David
 
Thanks guys,
I have yet to tear into it looking for faults. I have to clear a number of
other items off my bench before I start. It just looked to me like a screen
adjustment because it has a decent and proper display. I will keep the
following items in mind.
 
V

Vector Viper

Jan 1, 1970
0
I have a Dell UltraScan P991 (AKA Sony) monitor that exibits excessive
screen briteness and retrace lines. Opening it up and there is no pot
adjustment for screen
or G2 on the flyback or anywhere else I see. Is this adjusted with DAS
only?
If so, is there a workaround so I can adjust the screen voltage?
Any and all constructive comments welcome. Thanks!
Sometimes divider resistors change value or open, the values can
be changes to your advantage too, in a pinch...
 
A

Art

Jan 1, 1970
0
Possible that there is an adjustment physically on the crt drive board.
Check for leaky caps on the G2 supply line, check the video bias voltages
and caps on that suppply line. Etc. Suspect you will find either defective
caps or maybe resistors that have changed values.
 
W

Wayne

Jan 1, 1970
0
This is a common problem - search the Monitor Repair Forum at
http://www.network54.com/Forum/87612
for the string 'Dell P991 Brightness' and sort by 'Match'
You will get a lot of posts on this problem; looks like there is a
hardware fix.

Wayne
 
S

Sam Goldwasser

Jan 1, 1970
0
However, the main point to emphasize is that if these symptoms happened
suddenly, the problem isn't an adjustment. Only except might be that
if the function is controlled via software, a corrupt EEPROM could cause
it.

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