HowToFixComputers.com

Guest

I noticed my Samsung SyncMaster 763MB 17" CRT monitor has been blurrier. Maybe I am too used to
the LCD monitors at work, but they are still blurry even after looking at it for hours (yes, I
take breaks from the computer). But that is not a big deal.

The bigger deal is that I seem to notice very fine transparent horizontal lines (tilted maybe 5
degrees left?). I have to look hard to see them, but they are there with white or light gray
color. I tried playing with degauss, different refresh rates, brightness/contrast, checking
with another computer (different NVIDIA video cards too) with a different operating system
(Windows XP Pro. SP2 vs. Linux/Debian), etc.

The only thing that make it go away if I use 800x600, 960x600, and above 1280x720 (maximum is
1280x1024) pixels resolutions, then I don't see those lines. I also don't see the lines if I
don't set my monitor picture size (controlled by the CRT's front panel buttons [OSD]). The
MagicBright button is default at Text mode shows this. Setting to Internet or Entertain make
the lines go away.

Are these signs of a dying CRT? i had the monitor since 7/7/2002 and I use it almost daily.
Thank you in advance. smile

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Davy

The poor focus could well be the tube, it also could be the focus control just want's re-setting... the focus can drift with age and time because of the high value resistors and the high voltage involved.

The wavy lines, that's usually related to interference or HF ripples on what should be a steady DC supply line in the monitor, usually caused by failing smoothing or decoupling electrolytic capacitors, the ripples modulating the tubes beam current one way or another.

Once upon a time brand new CRT monitors could cost only peanuts to replace making the repair worthless, but with the demise of CRT's their replacement LCD and Plasma monitors being more expensive, at least for the time being.

The poor focus could also be caused by the line/flyback transformer itself, this produces the high voltages required during the 'flyback period'.

Sometimes a poor CRT can be rejuvenated with a 'tube booster' machine but these things are only a short term fix, sounds as though the monitor had a fair amount of 'clobber' and would suspect the tube being the cause of poor focus, the capacitors being the cause of the wavy patterns you can see.

One good clue of the tube consition is to look at the 'whites' in the picture, the white's should not be tinted or colourised..

Here is a link for a Monitor Test pattern that you can download-:
http://www.softpedia.com/get/Multimedia/Video/Other-VIDEO-Tools/Nokia-Monitor-Test.shtml

Davy

Guest

Davy <no@spam.invalid> wrote:

chrisv · Guest

ANTant@zimage.com wrote:

Guest

Uh oh. I think it is getting worse? I can see minor wavy stuff scrolling
vertically. It is like those video taped off a CRT TV/monitor to show on
TV. You see those moving lines vertically.

ANTant@zimage.com wrote:

Guest

Interesting. I set the refresh rate to 72hz and the annoying effects are
gone. Not sure how long this will stay stable.

ANTant@zimage.com wrote: