27K7501 Dim & Unfocused

Mat

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Looks like I'm gonna be learning a lot about monitors over the next month or so. I picked up a Gauntlet: Legends that's been converted to Dark Legacy and I believe it has a Wells Gardner 27K7501 in it.

The game plays but the picture is dim and kinda unfocused. The picture is so dim it's difficult to play even in the dark. I've got the brightness turned all the way up and the PCB dip switch is set to medium res. Also, everything has a blue tint to it. When I bring up the color bars, all three primaries can be seen. The blue tint isn't as bad as it appears in the picture below, but it's there.

Any ideas guys? I'm just getting started in this and don't know much.
 

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i fixed one for my friend just like that. same machine and game same monitor and chassis.

recapped the chassis and adjusted everything on the chassis.

turned out it was the tube a rejuve brought it back to life.

i would cap it re-flow the chassis and neck board and rejuve the tube.

Peace
Buffett
 
I haven't tried adjusting the neckboard pots but I'll give that a shot.

Should I replace all the caps or are their specific ones you would recommend?

I've heard people talk about tube rejuvenators but I don't know what they are. What exactly is it and how do you use one?

When you say "reflow", do you mean resoldering every single solder point on the board?
 
Start with a cap kit and see where it takes you.

The unfocused part is likely the flyback needing to be replaced.
 
replace all the caps.

re-flow all the transistors, header pins/yoke pins/ECT.. on the neck board and chassis along with the power supply section.

Peace
Buffett
 
Thanks guys, I'll check back in after I put in new caps. I don't know if my soldering skills are up to all that reflow work.
 
the re-flow work is necessary on this chassis to bring it back to life with less problems later.

the neck board transistors are hideously bad on this model.

Peace
Buffett
 
There is a resistor near where the remote board plugs in that has a habit of burning slap the fuck up. If it does, the whole screen does what yours is doing and looks really dark.

Sorry can't remember which resistor it is! Look and see if any look burnt within an inch or so of where the remote plugs in.

With that said though, you could just be missing both the red and green, like Buffett said the transistors on the neckboard get so hot they'll fall off! They have to be reworked a bit.
 
Make sure to check R811, also. When it goes open, you can get a very dim picture.

Can you describe to me where R811 is? I looked all over the board and I can't find it. I found a bunch of other R8XXs, but no R811.

Here's a pic of the board and an closeup of the right side.
 

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