I absolutely CAN NOT Sync my JRok multiWilliams

sbardelli

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I installed a multi Williams broken into my robotron. The monitor worked just fine prior.

Now, no matter what I try, I cannot get it to sync properly.

It really wants to scroll top to bottom. It never truly locks in. Even if I get the positioning just right... and start a game... by level 2 it moves. By level 3... it's cut in half... meaning the bottom half is now on the top.

What am I missing. I even installed another k4900... and it does the same thing.
 
did you run a new JAMMA harness to use with this or are you using the adapter board thing to retain the original Williams wiring?
 
I have tried two different sync connectors
 

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the JROK Robotron at work I have no recollection of how the video is rigged up. I don't remember there being anything extra for H+V so I imagine the video harness just absorbs composite sync into the old H pin?
 
I'm not sure what I'm looking at in your 2nd pic, but that connector with the white wires looks wrong to me. That has a jumper connecting negative H and V sync (sometimes used with composite sync), but I'm pretty sure Williams games use positive separate H and V sync. I'm sure the JROK board can use negative composite sync, but if you're using an adapter with the original wiring and the 2-pin connector, I'd guess it's using positive separate sync. In which case you shouldn't have that white jumper connector at all, and instead should have it connected to the appropriate pins I labeled +H and +V on the 6-pin connector.

And probably a long shot, but something to double-check... make sure everything is actually soldered. Here's a post where someone was having issues using a ZooQ w/ an Arcadeshop JAMMA adapter, and it turned out that the header and JAMMA adapter were only half soldered: https://forums.arcade-museum.com/th...shop-jamma-to-qix-static.544304/#post-4906564

DogP
 

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I'm not sure what I'm looking at in your 2nd pic, but that connector with the white wires looks wrong to me. That has a jumper connecting negative H and V sync (sometimes used with composite sync), but I'm pretty sure Williams games use positive separate H and V sync. I'm sure the JROK board can use negative composite sync, but if you're using an adapter with the original wiring and the 2-pin connector, I'd guess it's using positive separate sync. In which case you shouldn't have that white jumper connector at all, and instead should have it connected to the appropriate pins I labeled +H and +V on the 6-pin connector.

And probably a long shot, but something to double-check... make sure everything is actually soldered. Here's a post where someone was having issues using a ZooQ w/ an Arcadeshop JAMMA adapter, and it turned out that the header and JAMMA adapter were only half soldered: https://forums.arcade-museum.com/th...shop-jamma-to-qix-static.544304/#post-4906564

DogP
that's because it is wrong. I didn't catch that lol

violet-white wire is for horizontal sync. that's not getting to pin 10 and is most likely the problem. and obviously you'll need to fix the plug properly. solid violet was vertical sync.

also if the adapter board is used and the plug to the monitor is remaining the same then the JROK probably has a sync polarity option. I can dig a tunnel to the Robotron later today and see how that's rigged up.
 
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