Response from Jonathan: Ethan,

It sounds like you are having an issue in the high voltage section of your monitor chassis. We’ve seen cold/cracked solder joints on the high voltage line cause this problem. We would recommend starting off with that by removing the monitor chassis from the cabinet and seeing if you can find any solder joints that need to be touched up. It would also be a good idea to double check that your monitor chassis is getting power from your cabinet. You can check this with a multimeter pretty easily by setting it on the appropriate AC setting and placing the probes inside the connector that goes to your monitor chassis.

If you continue to have problems after checking these areas, the issue could be caused by the flyback itself or other parts on your monitor (Horizontal Output Transistor, resistors, capacitors, etc.). At this point, you will need to identify which monitor chassis you have in your Simpsons cabinet. The Zenith model that you mentioned in your email is for the monitor tube, not the chassis. If you are having problems determining the brand/model of your chassis, you can compare it to the pictures on the What’s My Monitor page by Bob Roberts and hopefully you can find a match. Once you know that, we can better help you troubleshoot this issue.

Hope that helps. Thank you for your question and keep us updated on your progress.