WPC lamp matrix and GI driver parts

Lamp columns use TIP107 transistors at Q91-Q98 and lamp rows use TIP102s at Q83-Q90. The five general illumination strings are switched by BT138 triacs at Q18 (string 1), Q10 (2), Q14 (3), Q16 (4) and Q12 (5).

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)

Related tips

• How the WPC lamp matrix works
• How the WPC lamp matrix is switched
• A lamp column or row stays on all the time
• A row or column of lamps stuck on and too bright
• Which transistor drives which WPC solenoid and lamp circuits
• BR1 (D11-D14 on WPC-95) and the board around it scorched
• A lamp row very bright or dead
• How a WPC coil, flasher or lamp driver chain works

Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer