New production A17 module Auxiliary Driver / General Illumination flasher board for early Bally solid state pinball machines.
The auxiliary driver board is used in some Bally games to control a switch called a triac. This switch turns specific lights on and off to create interesting effects. It works together with a lamp SCR on the lamp driver board. The triac is typically located on a bracket attached to the rectifier board mounting plate at the bottom of the game cabinet. Similar to the solenoid expander board, there is a small bulb near the auxiliary driver board. This bulb lights up when the auxiliary driver board is active. It's important for the proper functioning of the auxiliary driver because it helps a special chip called an opto isolator (MOC3011) on the board to work correctly.
Reference:
- AS-2518-68