K4900 Weird Screen

So I swapped out the chassis and the green was still missing. What should I start looking at now? Thanks.

if your problem stayed after switching to another chassis then it should be in your tube and i would put a tube tester on it and see if it can be fixed. if you rejuv it always use the lowest setting needed to fix it. if you don't have a tester/rejuvenator then i would see if someone local to you does or the sencore cr70 are pretty cheap and you don't need to make adapters but brand is only a preference of the individual. i personally use the cr7000 sencore and i like it the best but they are hard to find and high priced but excellent machines.
 
yup get your tube tested.

if your coming up this way anytime soon you can bring the tube by the shop.

Peace
Buffett
 
Ok so I turned the pot for the green gun and got a green hue evenly over the screen. I think that means the green isn't coming to to chassis from the pcb? Can that be a possibility? If so is there a green signal coming out of pcb or is all the colors in the same wire and it's a chip? Not sure since I'm a newb arcades.
 
it can be your PCB, wiring harness or a bad part on the chassis.

connect another game to your monitor to see if the green works or not.

if it does then your issue is the wiring or the PCB.

if you still don't have green then your chassis has an issue.

Peace
Buffett
 
Already swapped chassis and the good chassis didn't show green either. Is there a wire in ghost and goblins and other games that supplies the green color pattern for the game?
 
check your wiring harness and verify that you have continuity on the green wire from the PCB to the chassis.

Peace
Buffett
 
Okay so I disconnected the edge connector on the PCB and measure from the green wire on the connector to the soldered point on the chassis. There was continuity. Should I leave the edge connector off or what is my next move?
 
So if it could be the green wire why couldn't it be something on the PCB? The possibility of where would I look? Also when I did the cap kit, I wash tube and chassis with Simple green. When I put everything back together, the green would go in and out and now it doesn't seem like it's coming on at all. It seems I irritated something. And since it was working intermittently before and not working at all now it is either and I irritated it more swapping chessie's in and out or the problem just got worse over time and failed in a short time.
 
What you have here is 4 variables. The PCB, the chassis, the wiring and the tube. You have to eliminate one variable at a time. So far from what I have read is that maybe you have eliminated the chassis by swapping in a good one and the wiring should be okay since you have continuity. Now you need either another game to install the monitor in or a TPG (test pattern generator) to give you a known working video signal. With a known good video signal if you get green, it is a game board problem. If not it could possibly be a chassis problem (doubt this since you swapped in a working chassis) or a tube problem.

Ed
 
Thanks Ed! I like the break down. I found the issue. It was the wiring harness. When i wiggled the wire, the green would go in and out. Quick question... where can i get a inexpensive test pattern generator?
 
Thanks Ed! I like the break down. I found the issue. It was the wiring harness. When i wiggled the wire, the green would go in and out. Quick question... where can i get a inexpensive test pattern generator?

i would personally recommend the TPG since i have two of them since craftymech's first released them and they work great.
 
So I went and looked for craftymech's TPG and i found their website but no price or place to order. I then looked at teh rest of the links in google and found no place selling them. This guy might have some marketing issues if someone wants to purchase his item and they can find a place to buy it lol
 
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