Please help, G07 will not stop scrolling!

mrsodapop

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I got a G07 mounted vertically that will almost stop scrolling right/left. History-Installed cap kit,flyback, HOT, Hoz. width coil,and checked for cracks and poor solider joints(4X). Monitor looks fine when powered up, except will not stop scrolling. Searched here on KLOV for fixes. Checked/replaced R314,R317,R303,R306(all are 390ohm), replaced IC501, and replaced vertical hold pot. My B+ is 121vdc. I also installed another G07 chassis and it works fine, so I know it is not my wiring/game PCB.
This thing is driving me nuts, been working on it for 2-3 weeks now.
Thanks for any help
Aaron
 
Thanks for the reply, However that has been done, and rechecked (using a magnifying glass)a few times.
Aaron
 
Something in the sync circuit is amis.

Do you have any positive sync games you can test it with? Centipede? Food Fight?
 
I don't think any of my games (that aren't in storage right now)are pos. sync., most all are Jamma/ neg. sync. This is a 60 in 1 board I am using right now.
Thanks
Aaron
 
Do you have the sync jumpered on pins 2 and 3 of the back 3-pin connector?

The next thing would be to check that all of the vertical pots are good (the one just left of the v hold pot can cause it to roll) and verify the ground.

I recently dealt with this issue on a G07 on my test bench, and eventually found the problem by doing a continuity check between the JAMMA harness and the monitor. Apparently the vertical sync wire broke inside the insulation 2 inches from the video connector...
 
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