Red stopped working on Dell monitor

[My father's son]

I have a Dell Ultrascan VC8N 21 inch monitor which, because of its size, I
am reluctant to throw out. But the red has stopped working completely.
Nothing comes through at all. This isn't a driver or windows issue: When I
go to the screen settings on the XP desktop and try to check RED to adjust
it, all I get is black. Not even a minimal amount of red, and obviously no
red bleeding indicating that the tube itself is blowing

Is this sort of thing usually caused by something being knocked off the back
of the CRT like the red gun? Or is it likely to be more serious than that?
Is this a "Gently pull the CRT neck board off of the CRT and replace it"
problem? Or is it more likely an "if WHACK won't fix it (if only
momentarily), nothing will"

MFS

 

[James Sweet]

I have a Dell Ultrascan VC8N 21 inch monitor which, because of its size, I
am reluctant to throw out. But the red has stopped working completely.
Nothing comes through at all. This isn't a driver or windows issue: When I
go to the screen settings on the XP desktop and try to check RED to adjust
it, all I get is black. Not even a minimal amount of red, and obviously no
red bleeding indicating that the tube itself is blowing

Is this sort of thing usually caused by something being knocked off the back
of the CRT like the red gun? Or is it likely to be more serious than that?
Is this a "Gently pull the CRT neck board off of the CRT and replace it"
problem? Or is it more likely an "if WHACK won't fix it (if only
momentarily), nothing will"

MFS

The cause is very likely a solder joint or a bad drive transistor on the
neck board, also don't rule out silly things like the cable or video card, a
friend of mine was recently stumped working on his monitor and it turned out
the green output of the video card had failed. Worst case you can take it to
a shop and it'll likely be under $100 to fix. The tube is most certainly
*not* the problem.

 

[Jerry G.]

This can be anything from a break in the leads in the cable for the red
channel through the video processing, or the bias supply to the circuits
that drive the tube. The best way to check this is to follow the video path
with a scope and check the DC volts with a DVM, and see where the signal
stops. It is also possible that there is a problem in the circuit area that
supplies the bias volts for the red gun in the tube.

It is very rare that the red gun in the tube would fail completely all of a
sudden. Your best solution would be to take the monitor to a service centre
that specializes in monitors, and have them properly check it for you. This
is not a repair you can do at home, unless it is something very simple and
obvious.

An after thought, did you try another monitor to rule out the display card.
I have had a display card fail, causing a colour channel loss.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


I have a Dell Ultrascan VC8N 21 inch monitor which, because of its size, I
am reluctant to throw out. But the red has stopped working completely.
Nothing comes through at all. This isn't a driver or windows issue: When I
go to the screen settings on the XP desktop and try to check RED to adjust
it, all I get is black. Not even a minimal amount of red, and obviously no
red bleeding indicating that the tube itself is blowing

Is this sort of thing usually caused by something being knocked off the back
of the CRT like the red gun? Or is it likely to be more serious than that?
Is this a "Gently pull the CRT neck board off of the CRT and replace it"
problem? Or is it more likely an "if WHACK won't fix it (if only
momentarily), nothing will"

MFS

 

[My father's son]

Yes, I had that problem a few weeks ago and was amazed to find a completely
bent pin on the SVGA connector. I will plug my laptop into the SVGA cable
and see what happens

Sounds like too difficult to fix, after all if it were a bad solder joint a
whack should have done at least something?

 

[Sam Goldwasser]

Yes, I had that problem a few weeks ago and was amazed to find a completely
bent pin on the SVGA connector. I will plug my laptop into the SVGA cable
and see what happens

Sounds like too difficult to fix, after all if it were a bad solder joint a
whack should have done at least something?

Often but not always.

Are you saying that if it is anything more than a bad solder joint, it
isn't worth fixing?

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[My father's son]

Luckily what actually happened was that, on the unlikely suggestion, I tried
changing the SVGA wire which went from my Belkin monitor switch to the
computer with an unused one and the red started working immediately!