Qbert JROK Sync question

usmccarr

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I'm trying to get my QBert JROK board to run in my Jamma wired QBert cabinet, but I'm not able to get it to sync. Tried another jamma board in the same cab, and it sync's immediately with no problems. Currently the horizontal sync and vertical sync pins have a jumper connecting them. Can anyone let me know what I need to adjust to get this to sync?

Thanks
 
Those aren't supposed to be jumpered together. That's a pin header that you connect to the arcadeshop " q*bert cabinet to jamma adapter" that then puts out separate H&V sync signals to the original q*bert cab's monitor. Also, do you have the VGA enabled jumper enabled? If so, change it back to standard res mode by disabling the VGA. Composite sync is provided at the JAMMA edge, per usual.
 
The horizontal and vertical sync pins that are jumpered are the ones that connect to the monitor chassis from the jamma harness. I see the 2 pins on the Jrok pcb you are referring to. Nothing has been done to those. I plugged the pcb into another jamma cab and it synced right away, so it's something with this cabs wiring.
 
Post a pic of the issue, it may be a case of H or V hold adjustment, unless you have already tried those…

p
 
Post a pic of the issue, it may be a case of H or V hold adjustment, unless you have already tried those…

p

Also post a photo of how you've got the sync hooked up to your monitor. What kind of monitor is it?
 
I was able to get it to sync by adjusting the hold on the chassis (I had assumed that since the sync was good with another game, it should be good on this one….) total bonehead move by me.

Now, I'm struggling to get the image centered. See attached. I'm only able to adjust the horizontal position so much in either direction, and it's not enough to end with 1 image filling the screen out. FYI. This is a Vison Pro crt.

IMG_9831.jpeg
 
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Anyone have any ideas what would cause the image to display this way? I tried it in another jamma cab and I'm getting the same thing.
 
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