CRT monitor acting like an LCD !?


I have a 21" Dell CRT monitor. About a third of the way from the top
of the screen there is a horizontal line - just like you see when an
entire line of pixels fails on an LCD monitor. It's only very faint
at the moment. The line is dead still (doesn't roll with the refresh
rate) and it is (obviously) more noticeable when the screen is white
or the white mouse pointer is positioned so the line passes through
it.
What would cause this kind of fault !?
Allan.
Reply to
(Just) Allan
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HI, you will find there is also a horizontal 'line' about a third of the way from the bottom. These are support wires for the aperture grill. All Sony Trinitron CRT monitors have these 'lines'.
From a Google search...
Why do Trinitron monitors have one or two thin lines stretching across the width of the screen?
A single 'damper wire' (or two wires for bigger screen monitors) is placed horizontally across the vertical stripes of the Trinitron Aperture Grille. This holds the grille in place and limits possible vibration. Generally, the line is not visible, although it may be seen against a white background.
Wayne
Reply to
Wayne
Let me guess, you also have one about 1/3 of the way from the bottom as well. If so, you have a Trinitron monitor. It's just how they are made. There are two thin wires suspending the shadow mask behind the glass. They show up as thin, slightly darker horizontal lines. I like to point these out to people that have never noticed them before.
Reply to
Anthony Fremont
Thats normal for a Sony tube. My HP Monitor Has them as well...
Regards, Mitchell
Reply to
Mitchell McCreath
history?
a dark line and not a gap?
I had a gap on my screen caused by the magnetic field of the monitor beside it which was running at the same vertical sync rate.
If it's a used monitor it could be burn in.
Bye. Jasen
Reply to
Jasen Betts
Yep, you're both right - I bought a new system and had the choice of a 17" LCD for ~$450, but then saw the secondhand 21" Dell CRT for um... $180 I think it was. I'm *sure* the lines weren't there for an entire week. I only noticed the second line after posting the message. It just made no sense (surely the line should move or oscillate in SOME way!?)
I wonder if they all have this - probably not I guess, or they wouldn't have sold many.
Allan.
Reply to
(Just) Allan
I suggest you research Trinitron monitors and you will find the answer lies within - hint "shadow line".
Ray
Reply to
Ray
As long as it's not a real fault, I'm happy I guess. I don't suppose there's a way to minimise it at all? (I own a degaussing wand - don't suppose it would do much.) I wonder if the wire becomes more visible over time because of corrosion/contamination.
Reply to
(Just) Allan
Yeah, I turned off the other one - although I thought it could still be induction - but the other guys are right - there are two lines, so it sound like they nailed it.
Reply to
(Just) Allan
They are all like this, have been for many years and they've sold plenty. You don't notice them unless you are looking for them. I'd completely forgotten about mine and hadn't noticed them for a year until you reminded me. Thanks a lot ;-)
Michael
Reply to
Michael C
I have two digital 21" and an IBM 21" on the desk . all share the same tube as yours and all have the lines . use a darker background and forget it .
Reply to
atec
See if there is another one about a third from the bottom. I think there wil be one.
DELL, I beleive use SONY trinitron tubes and this is normal. What you see is "support for shadow mask". This is how Trinitrons ara made.
Rudolf
Reply to
Rudolf Ladyzhenskii
You're kidding? Mine has that. I thought I inherited a piece of junk.
In it's day it was a professional quality monitor with Trinitron tube. And it is supposed to have faint lines across the screen?
Also I can't get the image square using the OSD, and apparently there is no service mode.
Reply to
Tom Smyth
Look up Trinitron on the Internet. This will explain why you have the lines.
Realistically, working with monitor like that you will stop noticing them very quickly.
As for getting picture square, there should be adjustments for it. Some monitors have service mode, some have service port and you need special hardware/software to access it. Some have internal pots. Most SONYs had the service port, so only SONY service center can help you there. When I had SONY for repairs and they needed asjustments I usually soldered in couple of resistors.
Rudolf
Reply to
Rudolf
"Rudolf" wrote in news:43cad63d snipped-for-privacy@news.iprimus.com.au:
I had never noticed the lines in the big Trinitron that I work with every day, until a friend said "Ahh, Trinitron, yes, once I point out those two black lines to you, you'll never be able to ignore them again!".
I could have killed her right there and then!
GB
--
"When all you have is a flamethrower, everything looks like a 
 speed camera." (Peter)
Reply to
GB

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