Hi all,

Picked up a Space Mission project machine recently and I'm not sure how to resolve this issue. The coil for the 1-Point stepper for player 1 is roasted, which isn't a huge deal - something is stuck somewhere that needs to be unstuck. The problem is that according to the schematic (https://www.ipdb.org/files/2253/Williams_1976_Space_Mission_Schematic_Diagram_continuous.pdf) this coil doesn't exist as far as I can tell, so I can't trace it back to whatever is energizing it. There does seem to be an issue with the 50-point relay since the 3 switches (circled below) advance the score unit but not the 10-Point DU; however, the 10-point relay works fine, and I can't imagine why a bad 50-point relay would cause problems with the 1-Point stepper coil. So, my big question: why is the 1-Point DU/coil not indicated in the schematics, and what could keep it constantly energized?

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Is there anything more specific I should check besides "everything?" I would assume the purpose of having the coil on an unused reel would be to set it back to 0 if it ever got moved back somehow, but I've already checked all the switches on the reset stack and they're ok. what would it be "piggybacking" off of it doesn't have its own circuit?

You’re reading it correctly. There is a stepper unit for the scoring reel that would be the rightmost one when standing in front of the machine. If incremented once after a reset, the score would read 00001. You can push the stepper arm with your finger and it will increment the reel. There’s nothing worth <10 points in the game, but there’s a coil there that’s absolutely scorched. All 4 players have coils and steppers in that position, but only player 1’s has the look and texture of an Arby’s curly fry. I’m trying to figure out where the heck the power is coming from.

The 10-point reel acts normal in every way except for failing to increment when the 50-point relay is activated, but that’s true for all 4 players and the other 3 don’t look like they’ve been charbroiled.

Unfortunately, I immediately realized after posting this topic that it was a terrible time to do so because I won’t be getting back to my workspace until Monday. However, so many of you guys seem so certain that I’m wrong that I’m starting to believe that maybe I just can’t count to 4. I’m going to triple-check the reels Monday and if I’m just that dumb then I’ll have to eat a flipper rubber or something to make up for it.

So... anybody got any good flipper rubber recipes? Asking for a friend.

Well, I guess there's my complete inability to do basic arithmetic, so if you have any advice in that regard I'm apparently in desperate need of it. Otherwise I should be able to handle it from here now that I'm no longer chasing a circuit that doesn't exist.

I do have another question that may warrant a separate thread, but might as well throw it out there. Is there a replacement part for these light diffuser tubes? There are two more in the top right of the table behind the standup target and one of them crumbled into dust when I removed it. I'm sure I can find a functional replacement at Home Depot if I need to but I'd rather use the "right" part if possible.

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Awesome, thanks!