A few days ago I got the time to take a look at my Asteroids that I bought earlier this year. The machine is in really sad shape and the monitor was no exception. The machine looked like it went through hell inside and out. The boards were absolutely filthy.
It barely displayed the upper right hand corner of the screen when it was on and lately it only displayed a vertical line. It was obvious there was something wrong with the deflection circuitry, (or the connectors to them). So, I started right away by pulling everything out and testing all the relative circuitry and cleaning up the boards real good in the process. I got them to a finely-honed shine. They may not of worked but they sure were clean! ;)
Anyway, I ordered the bulk of what was busted on the regulator PCB through Bob Roberts. By the way, I'm still amazed at all the stuff that guy has readily available. If you're ever looking for parts, look through him first. He's the best. Period.
Almost everything on the regulator board was bad... diodes, resistors, transistors, the caps were dry... the whole damn thing was pretty much screwed except for the bridge rectifier.
Strangely, the deflection amplifiers board was fine.
I soldered everything back up and popped all the boards in and 'voila'... the screen came up... in German. ;) A few dip switch settings later the game was working perfect!
I love a happy ending. Now I just gotta' put the new volcano buttons on, find 5 new white leafswitch buttons, repaint the CP, rebuild the cabinet, put the new side art on and replace the bezel and I'm set! ;)