Response from Jonathan: Ben,

Actually you would be surprised… 😉 Usually this glitch is caused by either the horizontal hold and/or vertical hold adjustment on the monitor not being “locked in.” Basically, the potentiometer (or pot) value of the adjustment is just enough to keep the picture stable but when something on the screen flashes or the picture changes, the value is no longer adequate to keep the screen in check. Try adjusting these two pots on your monitor chassis just a bit to see if it helps the issue. If the problem continues, you may need to replace the pots altogether. Check out our post on Adjusting An Arcade Monitor for more information.

Another area we highly recommend checking is the wiring that runs from the Ms. Pac Man board to the monitor chassis along with the input pins where these wires connect on the monitor itself. If the connection is weak between the main board and the monitor it can cause issues like this. Also, make sure you touch up the solder on the monitor input pins on the monitor chassis. A cracked or cold solder joint can cause your picture to have problems like this as well.

Hope that helps. Thank you for your question and good luck with your repair.

P.S. – Cute baby in the video. You’re definitely raising that kid right! 😉