I'm purging the demons from a Skateball. Lots of lamps out on this one (bulbs are ok). I've replaced some SCR that tested as bad on the lamp board, and repinned J1, J2, & J4. Still a dozen or so lamps out and they stay that way when I swap lamp board with Flash Gordon, so I expect bad sockets for most(will try jumpering to a test socket shortly). But...
I have a couple lamps that work in attract mode and not in lamp test mode. What's up with that? Are test modes sometimes unreliable? Are lamps also controlled by something on the MPU? Bad chip? I don't know what to make of this.
Thanks!