K4600 Monitor issues

egoodie06

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I posted another thread in the arcade machine repair; but since this monitor is having such weird issues I thought I'd move it here for help.

So this is a K4600 chassis. The tube it came with was cracked, so I tube swapped it, kept the original yoke on. I never knew if this monitor worked to begin with because I wasn't the previous owner.

However it has a weird issue where all of the R G B guns are just on. I can turn the brightness and all of that down and it does nothing. It's not the screen adjustment or any other. I've messed with it for days.

So, I tested it with a pattern generator, no luck. Even with no video signal it still does it. Monitor hasn't been recapped yet.


Whenever you put a video signal it, it shows up very faintly, you can also see it as shadow like underneath the colors. It's almost inverted like, where instead of filling in colors it colors the whole outside. The video syncs properly and scales, no issue there.


I'd be interested in possibly sending the board to someone to look at or repair.. has anyone seen this issue before?
 

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black level pot on the signal card. they get wear spots from sitting in the same place for like 100 years, usually I see them where it's a permanent black screen and if you wipe it you'll get a flash of white for like a millisecond.
 
black level pot on the signal card. they get wear spots from sitting in the same place for like 100 years, usually I see them where it's a permanent black screen and if you wipe it you'll get a flash of white for like a millisecond.
Tried to wiggle it and clean it. No change, doesn't affect the screen. I've also re flowed the two daughter boards as well with no luck.
 
Tried to wiggle it and clean it. No change, doesn't affect the screen. I've also re flowed the two daughter boards as well with no luck.
then it's bad and you need a new one. I apologize for leaving out the part where if it wears out, it's bad and you have to replace it. lol what I was suggesting before is how to diagnose that it is bad.
 
When you swapped the tube did you check if the pinout was the same if the tube number was different?
 
What is the tube # you used and did you check that the yoke is compatible or was it from another 4600?

You can send the monitor boards to me if you want them checked over or repaired.
 
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