Telling a -133 MPU from a -35 or -17

Look by J4 pin 19, between the large inductors L1 and L2: a diode (CR52) means a -133 board (six flashes); a resistor (R113) means -35 or -17 (seven flashes). A 2732 and a 2532 at U2 and U6 also hint at a -133 with Baby Pac-Man or Granny and the Gators code.

Systems

• Bally MPU AS-2518-35

Games

• Baby Pac-Man
• Grand Slam
• Granny and the Gators

Related tips

• Game will not boot, or MPU damaged, after swapping -35 and -133 boards
• Tell a -35/-133 MPU from a -17 by counting J5 pins
• Bench-testing a -133 MPU: swap the R113 diode for a resistor
• Convert a -35 MPU to a -133 for Baby Pac-Man and similar games
• -17, -35 and -133 MPU boards compared
• Telling a -17 MPU from a -35 by connector J5
• Convert a -133 MPU to a -35
• Jumpers for a -35/-133 MPU running two 2732 EPROMs (U2 and U6)

Source: Repairing Bally Electronic Pinball Games from 1977 to 1985, Part Two, Clay Harrell (pinrepair.com)