Hey everyone! I finally got my hands on my first System 1 game - Sinbad! I tried to do the free play mod that's on PinWiki, but it doesn't seem to work for me - just to test, I used alligator clips, and jumped Grn/Wht to Or/Wht on the diode strip but when I hit the credit button, nothing happens, and I can't even manually add credits on the coin switches - it doesn't register at all. As soon as I pull the jumper it adds credits and plays fine. So what am I missing? Original Gottlieb boards except for a Rottendog power supply, if that matters at all.

The game also has a button on the front that I am guessing someone tried to rig to add credits to the machine, but it doesn't do anything, so I'm wondering if that's my problem? Pics of that are attached, in case someone can tell me what it might do - they spliced into the Or/Wht and Yellow wires on the coin door wiring, and the Yellow wire looks like it goes to ground on the tilt bob.

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Update - after messing around a bit more, I jumped Grn/Wht to Brn/Wht and that worked. Now when you hit credit button, it increments a credit and then immediately decrements it.

I assume the other hack is attempting to add credits, but there must be something up with that Orange/White because it does nothing. That's an investigation for another day, I suppose.