I have been working on one. This is a learning experience because I haven't worked on a pin with this particular set of boards. I am used to System 11 and WPC. So far, I have rebuilt the transformer board and the voltage regulators on the driver board. Also replaced a few bad transistors on the driver board. I have the proper voltages at all of the test points. The CPU powers up and the GI and most inserts are working (probably a few bad components on the board that runs the inserts).

Now that I have voltage, the problem is that all of the coils (except the flippers... they work fine) seem to fire all together as soon as the machine is powered on, and the 1amp fuse under the playfield immediately blows. Trying to figure out what that might be... I am guessing that something is shorted under the playfield, but why would ALL of the coils fire? Weird stuff.

IMG_20140216_105033_182.jpgIMG_20140216_105041_687.jpg

I was actually thinking about replacing the IC on the driver board U1, U2, U3, and U4 next.

http://bigdaddy-enterprises.com/pdf/bally-solenoid.pdf

•1 ea. 74154 4-to-16 Decoder
•3 ea. 3081 Transistor Array IC

10-4 that. I will test and see..

Thanks for your help!