NO red in 25 in monitor...HELP... please...

Mark C

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Apr 10, 2003, 10:58:14 AM4/10/03

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Why would I not have red in my monitor?...I believe this is a
WG2547...25in monitor that was in a MK4 cab...How do I go about fixing
the problem?

Thanks for the help--the Doc

Brian Crowe

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Apr 10, 2003, 2:05:55 PM4/10/03

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It could be a chasis problem but I have had alot of 25" tubes go bad. 25"
inch tubes just don't seem to hold up well compared to 19".

"Mark C" <drmoon...@aol.com> wrote in message
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baraka

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Apr 10, 2003, 2:04:39 PM4/10/03

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drmoon...@aol.com (Mark C) wrote in message news:<50d8d3f8.03041...@posting.google.com>...

Check the 3 legged transistors. They are the barrel kind. If they the
legs are pinched together, you may not get red color to the monitor.
John

Marty Gardner

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Apr 10, 2003, 3:59:54 PM4/10/03

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I had this problem last year.
Here are my notes (compiled from other peoples newsgroup posts)
It ended up being a cold solder joint.

check square connector
check for cold solder on monitor board
check for cold solder behind red pin
check continuity between pcb and square connector
clean connector to pcb with rubbing alchohol

------------------------
This is a little technical, but if you can follow BE CAREFUL!
On the neck board of your monitor you will see three transistors with metal
tabs, each of these transistors is a colour, and if you connect MOMENTARILY
the tab to the metal frame of the chassis with a jumper wire you will be
able
to see which colour it is. No mistaking the colour! Now if the screen lights
up with BLUE & GREEN when you short those tabs but the red is not present
or much dimmer then your picture tube has either a shorted gun OR the gun
has died completely. It is sometimes possible for a picture tube to be
rejuvinated, but that's another story (check with your local TV repair
shops untill you find someone that knows how to do this). If you get RED,
then
you have a problem in the monitor, usually the transistor on the neck board
for the red gun has opened, replace it first, if you are cheap try the
transistor from either the blue or green gun to see if that is it. IF you
still don't get a red picture after subbing the transistor and firing up
the game (minus the colour whose transistor you "borrowed"), then the
problem is on the mother board of the monitor, and a schematic would be
usefull here.....

(i.e. no red tint, bad monitor) make sure the pins between the neckboard
and the tube are clean, straight and not squished.

Try swapping the red and
green inputs if you see red on your monitor and no green, then it is NOT the
tube. If you see no red still but still get a green where red should be I
would suspect a bad chassis.

>To correct this, turn down the red pot until the red lines do not show
>anymore. If turning the pot does nothing, then you need a new pot most
>likely. Check your solder to see that you arent shorting past the pot...
>(if you pull the pot entirely, you can test on both sides of it with your
>multimeter to see if there is a short there that you dont know about)

----------
In article <ypila.6558$h%2.32...@read1.cgocable.net>, "Brian Crowe"

Ken Layton

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Apr 10, 2003, 6:17:57 PM4/10/03

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Could be the pix tube. I've had to 'rejuvenate' alot of 25" tubes
lately.

Ken Layton KLayt...@aol.com Washington state resident (unsolicited
emails "Spam" sent to residents of Washington state are illegal under
Washington state law. Violators are prosecuted and can result in fines
of $500 PER instance).

Dave Whitman

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Apr 10, 2003, 9:48:14 PM4/10/03

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"Mark C" <drmoon...@aol.com> wrote in message
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More than likely you have a shorted color output transisitor.Very common on
these monitors.

Brian Crowe

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Apr 10, 2003, 11:40:00 PM4/10/03

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if the transistor was shorted wouldn't he have full red brightness?

"Dave Whitman" <dwhi...@triad.rr.com> wrote in message
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