MV-1F has wavy display in the upper corners?

[tomwaits]

I've got an MV-1F that's showing wavy distortion in the upper corners of the display on my RGB monitor. My MV-1C doesn't distort at all on the same monitor.


Here's a pic of the cross hatch pattern test from the MV-1F:

Does this look like a PCB problem? Or are the sync timings a little different on the MV-1F and not quite compatible with my monitor? Any suggestions?

Thanks!

 

[NEO-GEO man]

Cant say ive seen that before, does it wave or just stay still like that?

Can you try it on another display?

 

[malignantpoodle]

Xian Xi had commented on this before. Something about the PCB itself, I think adding a resistor to the sync line or something... can't remember. Hopefully he can come along and chime in. Pretty sure it's the pcb and there is a simple fix.

 

[NEO-GEO man]

Im quite confident its the game board yes.

 

[tomwaits]

Cant say ive seen that before, does it wave or just stay still like that?

Can you try it on another display?

It doesn't wave or move at all, just a constant distortion in the top corners.

I tried it in both of my JAMMA cabs this morning. The distortion is visible on both. It's not as visible as my supergun's RGB monitor because some of the blue area is 'overscan' and stretched beyond the visible area in the cabs, but it's definitely still there. The MV-1C looks fine.

I searched old threads and saw a couple comments about adding a capacitor or resistor to the sync line. Those threads didn't sound like exactly the same issue, but maybe I'll experiment a little...

 

[dragonpt]

It doesn't wave or move at all, just a constant distortion in the top corners.

I tried it in both of my JAMMA cabs this morning. The distortion is visible on both. It's not as visible as my supergun's RGB monitor because some of the blue area is 'overscan' and stretched beyond the visible area in the cabs, but it's definitely still there. The MV-1C looks fine.

I searched old threads and saw a couple comments about adding a capacitor or resistor to the sync line. Those threads didn't sound like exactly the same issue, but maybe I'll experiment a little...

You can try adding an 1 k pot (Potentiometer) into the sync line

Add the pot like this:

sync input ----> to the middle pin
the other 2 pins are output and Ground