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DCrosby

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So I found this manual...
https://www.arcade-museum.com/manuals-monitors/Wells-Gardner-27d9200-33d9200.pdf
It shows pretty well how it's supposed to work, the issue is I get these glitches in the sync when I go through the RGB Molex KK 10 pin Connector.

This is with VGA : https://photos.app.goo.gl/24sNEdNfuAgZHa9g8

This is with Molex : https://photos.app.goo.gl/XSBdxheJ53qL7CaR7

I've tried other boards, and same deal, any board running through the Jamma Harness glitches any board running into VGA runs fine.
(Yes I'm aware you have to swap over the cable going to the board from VGA to CGA/EGA

I realize this is less than ideal, as the connector is suspect, I did verify through the jamma harness I have continuity... but it's what I have while I wait for a proper KK connector so I can make a proper wire...
1713848983509.png

Any help of how this is supposed to be wired would be great...
I also saw that some WG connectors use the 3 pins at the end for Ground, H/S, V/S Comp, so I don't know if I need a second ground, or should just move those 3 down, and if it matters....
 
I looks like you have sync tied to the v sync input too. Remove the loop and move the white wire down one pin so it's on sync only.
 
Take a look at the underside of that little connector board… things are usually crispy and might gave you hints
 
So this was from another WG (Different) monitor, that I had in the past... so what you're saying is I only need Horizontal Sync H/S ?
1713881271966.png
 
You only need one. Jamma sync is composite sync, which is connected to the horizontal sync input. The two different connections on the monitor are either identical or ones for positive and ones for negative, depending on your source. Jamma games are negative composite sync.

On older WG models the pins in the middle are positive, and the ones on the end are negative. The manual for this monitor doesn't specify. Just try both (but not at the same time). In my experience with this monitor, I used the middle h sync input.
 
Cool, thank you that makes a lot of sense, I lacked the context for why the pins were repeated...
 
Funny, before I posted I tried to put the wire just in the V/S Slot.. and remove it from H/S as well as removing the ground, all of which made it worse... but as fate would have it the only thing I didn't try was putting the white wire into the H/S slot, and it works straight out of the gate....
 
This is how it ended up, and works. (I removed the sketchy punch through wires)
And you'd need to move the connector at the top over to CGA/EGA as well... (To make it work)
1714362598046.png
 
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