New Project: Tetris Cabaret

Turned on the 4800 before work. Turned up both the green gain and green cut off, both work fine. It does seem to put a little bit too much green or not enough green just like the other ones. Plus once I get the image centered Horizontally, it starts to bow super bad.

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Same as the kortek right? Monitor tube makes green, which is good. The green problem is upstream. That's consistent with the game board signal / bad wire theory.
 
I know this is usually a pain - but do you have another cabinet or test rig where you could connect this pcb and one of these 13" monitors? If you saw it with all colors there, it would help, right?
 
I know this is usually a pain - but do you have another cabinet or test rig where you could connect this pcb and one of these 13" monitors? If you saw it with all colors there, it would help, right?
Yeah, sounds easy enough to hook it all up with another harness. It's just a time factor. Gotta find all the stuff, lay it all out, hook it all up, etc. Then having two teenagers in the house, I can't leave stuff out while I'm not there working on it or they'll just move it or break it or throw a basketball in the middle of it.
 
But it most certainly could be a wiring issue. The Kortek has a weird non-standard header much like a Sanyo. I had to make an adapter for that with a 6-pos molex connector at the other end. So for all the other monitors, I've been basically making adapters with the same 6-pos molex at one end and the correct connector(s) for each chassis header on the other. Since there's only one sync wire from the JAMMA edge connector, I've split that sync wire into 2 with a wire loop. I know that red is matched with red, blue is matched with blue and green is matched with green, but someone had mentioned it could be a ground issue. I hooked everything up in order, but maybe the ground needs to go to the second set of header pins rather than the first one. Same with the sync wires, there are like four possible pin connections to make this all work correctly with each monitor. There's just so many little factors that could be causing these issues. The thing is, in all these years I've done this, I've never had this kind of thing happen. Usually, it's just a sync thing. Once you figure that out, everything works great. Never had these color issues before.
 
Turned on the 4800 before work. Turned up both the green gain and green cut off, both work fine. It does seem to put a little bit too much green or not enough green just like the other ones. Plus once I get the image centered Horizontally, it starts to bow super bad.

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If you turn up the Green gain and cutoff high enough, even without a signal, you will see green on the screen.

Like I said in my previous post, I still think you have a video ground issue with the colors . Did you try splicing a wire from video ground to power supply ground?
 
Yeah, sounds easy enough to hook it all up with another harness. It's just a time factor. Gotta find all the stuff, lay it all out, hook it all up, etc. Then having two teenagers in the house, I can't leave stuff out while I'm not there working on it or they'll just move it or break it or throw a basketball in the middle of it.

I understand that. Years ago I had all the guts to a jamma game screwed onto a piece of plywood with a handle cut in it, it helped. Eventually a buddy took parts from it or something.

A couple of years ago I splurged for a TPG, that's been nice to have. (Capped my 720 monitor successfully, made zero difference in the flaws in the picture, which seems to be the case most of the time for me.).

Having the right tools makes things so much better, but at this stage of my life/this hobby, I'm trying to only buy what's necessary. Though I did just order a bunch of stuff including better crimpers from APAR.

Anyway, you're really close, not many things left to rule out.
 
If you turn up the Green gain and cutoff high enough, even without a signal, you will see green on the screen.

Like I said in my previous post, I still think you have a video ground issue with the colors . Did you try splicing a wire from video ground to power supply ground?
Except on the Kortek, the green gain does nothing no matter how far you turn it in either direction. That's part of the problem. That's why I tried switching the blue and green pots to see if that changed anything, it did not. And I already acknowledged your ground idea in one of my last two or three posts.
 
Except on the Kortek, the green gain does nothing no matter how far you turn it in either direction. That's part of the problem. That's why I tried switching the blue and green pots to see if that changed anything, it did not. And I already acknowledged your ground idea in one of my last two or three posts.
My apologies. I was only trying to help. Good luck and hope you get everything sorted out.
 
Except on the Kortek, the green gain does nothing no matter how far you turn it in either direction. That's part of the problem. That's why I tried switching the blue and green pots to see if that changed anything, it did not. And I already acknowledged your ground idea in one of my last two or three posts.
How about swapping the transistors on the neck board?
 
OK, so I let it burn in for a half hour. Came back, tried to put the back door on. Bumped the neck board slightly and we're back to this. What the fuck.

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OK, so I let it burn in for a half hour. Came back, tried to put the back door on. Bumped the neck board slightly and we're back to this. What the fuck.

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Seemed like when I removed the header connector coming from the neck board to the chassis and then put the green gain pot back in and made sure there was solder connecting the pot leg with the pad next to it, everything finally seemed to work. I don't think that solder bridge would've gotten broken just nudging the neck board a little bit, would it? Otherwise, the green neck board transistor, could that be bad?
 
Well, I swapped the green and blue pots back on the chassis. Reflowed the solder on the header pins and made sure that there was continuity between the green pot and the green circuit. And somehow I fixed the Kortek.

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Maybe just due to moving the harness around in the process?
 
I'm still wondering why all your monitors and pcbs lack green so often. I still suspect the wiring harness. Do you have a way to rule it out?
For the 80th time, there's nothing wrong with the harness. This is in the monitor/connections. I didn't mess with the harness one bit. I just reflowed some solder on the header pins and did what I said on the monitor chassis and it worked. It had nothing to do with the harness. There's gotta be a bad solder joint, a bad header pin, a bad transistor, something. I brought this over to the monitor repair section where I might maybe get some tech help.
 
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For the 80th time, there's nothing wrong with the harness. This is in the monitor/connections. I didn't mess with the harness one bit. I just reflowed some solder on the header pins and did what I said on the monitor chassis and it worked. It had nothing to do with the harness. There's gotta be a bad solder joint, a bad header pin, a bad transistor, something. I brought this over to the monitor repair section where I might maybe get some tech help.
The harness connects to the header pins, right? From what you described, it sounded plausible that an intermittent green connection was still at play, because I would move the monitor or connector if I were reflowing pins, but maybe you did it some other way. Also you haven't proven any of the parts are reliable by themselves, out of the whole system.

Ok, I'll just sit back and watch this play out.
 
The harness connects to the header pins, right? From what you described, it sounded plausible that an intermittent green connection was still at play, because I would move the monitor or connector if I were reflowing pins, but maybe you did it some other way. Also you haven't proven any of the parts are reliable by themselves, out of the whole system.

Ok, I'll just sit back and watch this play out.
I would also do "the wiggle test" on the harness wires while it's powered on. Rules out (most of the time) cold solder joints.

P.S. @Phetishboy , if you were local, I'd be there in a heartbeat to help you troubleshoot. Over a beer or two! :cool:

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