Unless you have an Alltek board you cannot set free play on the early Bally's. What most people do is to set the first replay level at say 10,000 points. That way each time you play it will perpetuate a free game.

+1. Set max credits to 40 and replay threshold as low as it will go.

NO!

If you want a proper free play, you buy an Altek Ultimate MPU board which has a free play option built in. Another plus is that you don't need batteries with the Altek so no leakage problems.

I wired up an old bally with a separate start switch stacked with the existing start switch. I disconnected the wired from the coin switch and connected to this switch. Every start press added a credit.

Note: this interrupts the tone of your game uses a different sound for start as credit.

Sadly, no. I just put on 40 credits and run them down. That takes quite a while to play off 40 games.

I used to leave the replay score low but it made me sad to hear it go off all of the time and removed the joy of hearing it go off when I was doing a good job playing.

I thought that were game ROMs that allowed the stock boards to run w/free play option?!? But I agree the Altek boards are the best option for this on Bally games. Now if we could only get them to make a version that allowed this for the Stern pins as well...

If you have the ROM that fixes the bonus bug, you can set the dip switch 25 and dip switch 26 to "ON" and then freeplay is enabled.

If you have the factory ROM, you will need to burn a new one:

http://www.pinball4you.ch/okaegi/pro_soft.html

I used to just wire a credit button where the coin door lock went.

+1 for easy replay. Super easy and takes 2 secs to setup in the menus.

Vid, as always, thanks for the great info and link. I did not know that software existed. I will put it in the pile of things to do the next time I set-up the chip burner.

If you have an original ROM on your MPU board, and you find and burn the ROM Vid's talking about, you may have to rejumper your MPU board.

It's not a big deal to do, but something to know ahead of time.

+1 to getting the rom and doing the jumpers, they are quite easy. Of course many sites don't mention that on a -35 board the 9-12 jumper should be there. I burn home roms for my games and for friends machines to save the hassle.