Some time on or after 1992 the solenoid driver board was replaced with a Bally driver board. There is evidence of smoke above the location of the driver board. Picked up a real clean Stern SDU-100 Driver Board on ebay for a good price but untested. Did all the ground modes and replaced the two large caps as recommended C23 and C26. Tested all outputs and then did a solenoid test and tested out good.
