I am close to finished restoring my Bally Playboy, and finally got around to plugging it in for the first time this morning. I believed this machine to be working when purchased, though I don't know first hand (I was not there when it was purchased, and it was already partially torn down when I got it). I did have to replace the Transformer board, as it was all melted from the PO (I used an Nvram/Weebly Board as replacement).

When I initially plugged it in Lights came on, no displays, and about 10 seconds in significant smoke came out of the backbox!

Looking into it, it *looks* like pin 10 on the SOLENOID DRIVER J3 plug of the Solenoid driver board overheated and melted the plug, and that pin appears to be to traced to the transformer Pin17 of the TRANSFORMER J3 Plug The transformer plug is fine and shows no ill use.The smoke got out hereBack of Solenoid Driver Board, where J3 Plug goes

One Thing I'll note at the outset is I probably should have put more stock in the old Tech's taped note on it saying "No Power to Displays", but I honestly didn't think it was bad, since it booted before pickup. Maybe he knew something

So, what I'm trying to figure out is if (a) I just replace the board with an Altek one (which I'm fine doing) and I should be fine, or (b) if there might be something else going on here and might cause a (potentially catastrophic) failure with a new board as well.

One thing I just noticed when I was rechecking my wiring was on the new TRANSFORMER board J3 plug, I had the 2 Orange wires for Pin8 and Pin 10 swapped. I note from the schematics now Pin 8 solid orange is supposed to go to Pin 12 on the J3 plug for the solenoid board. All are Solid orange. Not sure if this makes any difference.

Also, any ideas on sources for a replacement plug?

Ugh! I also put in a new Alltek light board. Hopefully I didn't fry that too.

Ordered a New Alltek Solenoid board, since I didn't want to futz with an unknown previously messed with board. Any recommendations on how to start this up for the first time?

I'm thinking something like this:
Step 1) just unplug everything and check something on the Transformer board first (not sure what)
Step 2) Add the Solenoid driver second and check something
Step 3) Plug in MPU/Light board

Any thoughts are greatly appreciated to not cause any more damage!