I've recently purchased an upright Midway Space Invaders cabinet which I'd like to restore to working condition. This is my first experience with an arcade cabinet.
After cleaning it up and re-seating all of the connectors, I was able to get the game to the point where it will power up and appears to work and play, with two exceptions - no sound, which I'll deal with later, and the issue I'm trying to resolve now: the screen just rolls quickly, horizontally, from right to left. You can see that the game is otherwise working; the attract screens work, and if you drop in a quarter, you can start the one player game and it appears to play ok.
My first thought was that it was a monitor problem, but after some basic troubleshooting I'm not sure that's the case. When I bought the cabinet, it came with a second motherboard / daughter board set. I think the spare set is from a cocktail version, as it has extra connectors which I've come to understand are for the extra player controls. I swapped out the boards, and all this spare set does is slowly flash four invaders on the screen on and off.
However, with the second board, although it's entirely useless from the perspective of playing the game, the monitor display doesn't roll at all - it's solid and steady. So if this second board can create a solid display, it can't be the monitor, right? But what could be wrong with the first board that would cause the horizontal sync to appear to be lost?
Any guidance anyone has for what I should be looking at would be greatly appreciated. I've read through as many of the relevant posts on this machine as I could find, and I will go through the power supply troubleshooting steps tonight - based on what I'm seeing, though, I guess I don't expect that to yield much for this particular problem (not that I really have any idea what I'm doing!).
Thanks!
After cleaning it up and re-seating all of the connectors, I was able to get the game to the point where it will power up and appears to work and play, with two exceptions - no sound, which I'll deal with later, and the issue I'm trying to resolve now: the screen just rolls quickly, horizontally, from right to left. You can see that the game is otherwise working; the attract screens work, and if you drop in a quarter, you can start the one player game and it appears to play ok.
My first thought was that it was a monitor problem, but after some basic troubleshooting I'm not sure that's the case. When I bought the cabinet, it came with a second motherboard / daughter board set. I think the spare set is from a cocktail version, as it has extra connectors which I've come to understand are for the extra player controls. I swapped out the boards, and all this spare set does is slowly flash four invaders on the screen on and off.
However, with the second board, although it's entirely useless from the perspective of playing the game, the monitor display doesn't roll at all - it's solid and steady. So if this second board can create a solid display, it can't be the monitor, right? But what could be wrong with the first board that would cause the horizontal sync to appear to be lost?
Any guidance anyone has for what I should be looking at would be greatly appreciated. I've read through as many of the relevant posts on this machine as I could find, and I will go through the power supply troubleshooting steps tonight - based on what I'm seeing, though, I guess I don't expect that to yield much for this particular problem (not that I really have any idea what I'm doing!).
Thanks!



