Reset section parts typically ruined by battery corrosion

U8 5101 RAM (450 ns) with a 22 pin machine-pin socket; C1,C2 820 pF ceramic; C5 4.7 uF tantalum; C3,C13,C80 0.01 uF ceramic; CR5,CR7 1N4148; CR8 green LED; CR44 1N4004; R1,R3,R24,R28 8.2K; R2 120K; R11 82 ohm 2 W; R12 270; R16 2K; R17 150K; R29 470 1/2 W; R107 3.3K; R112 1K; R134 4.7K; R140 20K; Q1,Q2 2N3904; Q5 2N4403; VR1 1N4738A. Resistors are 1/4 W 5% unless noted.

Systems

• Bally MPU AS-2518-17
• Bally MPU AS-2518-35
• Stern MPU-100
• Stern MPU-200

Related tips

• Repairing battery corrosion on the MPU
• Repair battery corrosion before chasing MPU flash codes
• Corrosion under MPU J4 can destroy every chip
• Fitting a remote AA battery pack
• U8 (5101) connections for ringing out corrosion damage
• Cut the original MPU battery off right away
• Bally-35 MPU: remove the on-board rechargeable battery before it leaks
• Memory cap or battery does not keep scores

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