Quoted from trueno92:If this thing was just bells and chimes id probably put it down, but I seriously LOVE those old 8-bit sound effects!! I wish there was a knocker for the extra ball however. I am curious to see why no one has mentioned it before that Atari pins don't seem to have a knocker for extra ball or when you hit 50,000 points. There is a longer and louder sound effect to make up for it I guess.
Atari coded a knocker output for replays and specials, but they left out the hardware to make it happen. In the manual for Middle Earth, they discuss the modification needed to make this work for audit counters, but the same changes can easily be made to drive a solenoid instead. All you need to do is add a TIP101 transistor, a couple of diodes, and a stolen knocker assembly from another game.
I'm in the process of doing this on a Middle Earth that I bought from the Church of the Silver Ball... I'll take lots of photos and document the modification.
