Midway Space Invaders problem....

[modessitt]

Fixed a power resetting problem on an upright Midway Space Invaders - original and beautiful.

Now it has a weird problem.

The game plays perfectly when playing 1-player. When you play a 2-player game, it won't fire for the 2nd player, although the move buttons work.

This uses the "L-shaped" board set. The first set of schematics I found for this game showed a separate fire input for the 2nd player, but that was for the sandwiched boards.  I finally found the proper schematics for the L-shape and see that it uses the same input wire for the fire, regardless of the player.

What is frying my brain is the fact that the fire works for the 1st player, but not the 2nd. The only thing I can think of is that one of the chips that is supposed to "switch" the program for the 2nd player's turn isn't allowing the fire input signal to be processed. Only problem is, I can't tell from the schematics which chip this would be.

Anyone ever encountered this problem before? Any help or advice would be greatly appreciated.

[modessitt]

Ended up getting it fixed.  Turns out the manual I had was for a different type of board set than the L-shaped board set and, while virtually identical, was missing a crucial change - that being that dipswitch 8 must be off, despite the Midway service bulletin saying it must be on.

Thanks for all those who looked in, and for the help on KLOV's forums that eventually solved it.