There are two major subsets of pinball machines: electro-meachanical (EM) and solid state (SS) pinballs. Electro-mechanical machines are machines prior to 1977-78 that use mechanical score reels and a series of open and closed switches, solenoids and relays to operate the game. Solid state machines are generally post-1976 games that use solid state electronics with digital displays.
Most electro-mechanicals follow the same principals generally in function. Solid-state machines, for the most part, do as well; however, the electronics in solid state machines depending on the era and manufacturer differ in design.
Here are the primary service specialties I handle:
I can repair some issues on electro-mechanical machines; however, they are not my primary service specialty as the bulk of my collection and experience are solid state machines. If you have an electro-mechanical machine that is in need of repair, please reach out as I will likely be able to help you. But, if I feel it is a repair that is above my knowledge level on that type of machine, I have several colleagues that focus more on electro-mechanicals that I will happily refer you to.
Bally Solid-State: -17 and -35 (1977-85), 6803 (1985-88)
Williams Solid-State: System 3-6, 7-9, 11, WPC, WPC-95 (1977-1999)
Gottlieb Solid-State: System 1, System 80A, System 3 (1977-1995)
Data East Pinball Machines (1987-1994)
Sega Pinball Machines (1994-1999)
Stern Pinball (1999-present)
Jersey Jack Pinball (2014-present)
Spooky Pinball (2015-present)