Response from Jonathan: Addison,

Sounds like an issue with either the high voltage section of your monitor chassis or the monitor tube. It could be an issue with the flyback itself or other parts on your monitor (Horizontal Output Transistor, resistors, capacitors, etc.). Your first order of business will be to identify which monitor chassis you have in your San Francisco Rush cabinet. 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.

If the tube is the issue, you can try to find a compatible replacement by looking at old TV tubes to see if you can find a compatible one (see https://web.archive.org/web/20080705201439/http://www.8liners.com/datatech/monitor.html for information) but it would probably be easier just to replace it with a new monitor. Hope that helps.