Pacman is red, not yellow?

smeatr0n

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Hi folks. I had a pacman fall into my lap. It was modified years ago to play PAC and Ms PAC.

I've gotten it booting again and I've fixed up the monitor. But one issue remains. Pacman is red. Ms pacman too.

It's hard to know where to start since the board is so modified, though I suspect it to be one of the original ic's, not the newly added roms. Any ideas where I should concentrate efforts?
 

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Yellow is made with Red + Green. It looks like you have no green.
Dang I thought inky was looking pretty decent but perhaps I still have a bad tube. All the color transistors tested good on the chassis. I may finally need to dust off my rejuvenator for this one. Thanks for your help.
 
Dang I thought inky was looking pretty decent but perhaps I still have a bad tube. All the color transistors tested good on the chassis. I may finally need to dust off my rejuvenator for this one. Thanks for your help.
I wouldn't jump to blaming the tube before checking it over with a known working board.
 
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I do have a working ms PAC cabinet. I'll swap PCBs to see if the issue follows.

I've checked for continuity for all wiring and circuits from the edge connector to the neckboard just to be sure, tested all the transistors and resistors on the green circuit and everything tests fine.

I'll report back with whatever I can learn from mixing and matching parts.
 
turn the RGB cutoffs up, does the screen tint to each of those colors? then your drive circuitry and tube are good.

the white balance doesn't look ideal but I think all the colors are present. I've never had color PROM faults on Pac-Man before so I don't know what that entails.
 
turn the RGB cutoffs up, does the screen tint to each of those colors? then your drive circuitry and tube are good.

the white balance doesn't look ideal but I think all the colors are present. I've never had color PROM faults on Pac-Man before so I don't know what that entails.
this is the easiest thing to do, IMO. OP, you say you have a working Ms. Pac board and that's not hard to do either but I'd definitely crank the colors on the monitor as an easy 1st thing
 
Okay so let's update this thread. The issue was indeed the CRT. As luck would have it a compatible tube just popped up for free on marketplace right down the road from me. I swapped the tube and yoke and we are in business, yellow pacman and everything. Case closed!
 

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2 things:

1. What was wrong with the tube specifically?

2. Unless your pictures are just out of focus, you still have some convergence issues.
 
2 things:

1. What was wrong with the tube specifically?

2. Unless your pictures are just out of focus, you still have some convergence issues.
1. No green. Green gun must be dead. I'll donate it to someone who can try and rejuv it, I don't have the adapter.

2. Still fine tuning the focus, but was really excited to see yellow. It's good enough now after some adjusting. Much better than before.

The donor tube was a 510WUB22 from a Nanao MS7-20S. It replaced the existing 19VJTP22 in the k4600. I couldn't find much into about the 510WUB on tubular. Just decided to yolo and see what happens.
 
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