I'm an idiot and Defender paid the price. Help.

YeastLord

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So, after a long ass haul I got my Defender all up and running great with a Jrok card. The monitor was dialed in. Rebuilt the controls. It was really coming along. The coin door was the last real issue. The wiring was butchered and nothing worked. So I figured I'd go for the easy fix and re-do the coin eject lights first. Had a beer and built a harness. Had another beer and hooked everything up. Turned it on. Zaps and sparking noises.
I had put the ground to the +6 volts and vice versa. So I ran juice through the earth ground on the game.
I unhooked my dumb shit light job and turned the game back on. Crazy wazy lines in the screen. I have over the last 3 months done the following to diagnose where my issue is without any change:
1. Put a new chassis into the game.
2. Bypassed all of the switches (on/off and door open killers)
3. Completely taken the coin door out of the loop.
4. Rebuilt the power supply stuff (filter, blocks, fuses and transformer) Literally everything including the wiring.
5. Swapped in a new switching power supply.
6. Pulled out the Jrok card and stuck it in another cab where it works fine.
7. Put another Jrok into Defender where it displayed the same issue.

Here are two images of what it's doing. The band of waviness just slowly loops from top to bottom over and over and the details look crappy. (The ship looks like it's missing a few pixels)

Does anyone have any ideas where I can check next? I'm solidly out of ideas.

Thanks as always for taking the time to help.
 

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no, I'm the bigger idiot than you by far

one day, about 12 years ago, I was sitting there working on a game trying to install a monitor into it
getting frustrated, I decided I was just going to install this other monitor that I knew would fit, so I stood up and accidently hit the neck board against the side of the cabinet which resulted in a mini implosion which made me jump and I let go of one side of the tube and it fell away onto the neck board of the first monitor and another implosion and I jumped again, tripped, and my foot just barely hit the neck board of the third monitor enough to knock the air out of it

all in less than 3 seconds probably.

3 perfectly working monitors with little to no screen burn, GONE

so don't feel too bad

looks like your jrok card is ok and the chassis too
not much else except the tube. try disconnecting the coin door and try again ???
looking like some kind of interference to me but I will be curious as to what the fix is so plz update good luck


.
 
no, I'm the bigger idiot than you by far

one day, about 12 years ago, I was sitting there working on a game trying to install a monitor into it
getting frustrated, I decided I was just going to install this other monitor that I knew would fit, so I stood up and accidently hit the neck board against the side of the cabinet which resulted in a mini implosion which made me jump and I let go of one side of the tube and it fell away onto the neck board of the first monitor and another implosion and I jumped again, tripped, and my foot just barely hit the neck board of the third monitor enough to knock the air out of it

all in less than 3 seconds probably.

3 perfectly working monitors with little to no screen burn, GONE

so don't feel too bad

looks like your jrok card is ok and the chassis too
not much else except the tube. try disconnecting the coin door and try again ???
looking like some kind of interference to me but I will be curious as to what the fix is so plz update good luck


.

dam dude that sucks.... that made me cry
 
Do you have ground connected to Earth ground?

I do. I went through and checked all of the EG connections. Would that produce the waviness that I'm seeing? If it would I'm going to go back through the whole thing again and make sure I didn't blow it.
 
no, I'm the bigger idiot than you by far

one day, about 12 years ago, I was sitting there working on a game trying to install a monitor into it
getting frustrated, I decided I was just going to install this other monitor that I knew would fit, so I stood up and accidently hit the neck board against the side of the cabinet which resulted in a mini implosion which made me jump and I let go of one side of the tube and it fell away onto the neck board of the first monitor and another implosion and I jumped again, tripped, and my foot just barely hit the neck board of the third monitor enough to knock the air out of it

all in less than 3 seconds probably.

3 perfectly working monitors with little to no screen burn, GONE

so don't feel too bad

looks like your jrok card is ok and the chassis too
not much else except the tube. try disconnecting the coin door and try again ???
looking like some kind of interference to me but I will be curious as to what the fix is so plz update good luck


.

I think I would have gone insane. That is the worst arcade related tragedy I'v ever heard. I hope you had a good source for monitors.
 
The pictures are kinda small to tell but it looks like maybe hum bars in the video. This is typically caused by a ground loop in the video circuit. I assume you still have the isolation transformer in the monitor circuit? Use a DMM on AC volts and measure between the video ground (at the monitor) and the video ground (at the PCB). If you see voltage then that's your issue. Next step would be to find out why. Possibly wiring error on the AC side to the monitor. Ground loop results when AC current is being drawn through the ground for some reason.
 
The pictures are kinda small to tell but it looks like maybe hum bars in the video. This is typically caused by a ground loop in the video circuit. I assume you still have the isolation transformer in the monitor circuit? Use a DMM on AC volts and measure between the video ground (at the monitor) and the video ground (at the PCB). If you see voltage then that's your issue. Next step would be to find out why. Possibly wiring error on the AC side to the monitor. Ground loop results when AC current is being drawn through the ground for some reason.

This is super helpful. I'll give it a try tonight and see if there's an issue.

Thanks again for the help!
 
I wanted to close this one out as I just found the issue. When I pumped +5V into the ground I fried a ground trace on the JROK to Defender harness adapter. It was just the tiniest burn but it was enough to cause the issue. Replaced the adapter and all is well with the world.
 
I wanted to close this one out as I just found the issue. When I pumped +5V into the ground I fried a ground trace on the JROK to Defender harness adapter. It was just the tiniest burn but it was enough to cause the issue. Replaced the adapter and all is well with the world.

Glad you got it fixed and shared the result!
 
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