Mount angle-sided C106 SCRs the right way round
Plastic C106 SCRs without a metal face look reversed compared to the metal-faced MCR106, because their printing is on the side that faces away. Orient them by the angled edge and the pinout, not by the lettering.
Systems
Related tips
- Test lamp SCRs with the power off
- Lamp driver board layout: SCRs, decoders and connectors
- A controlled lamp that is always on means a shorted SCR
- Prove the lamp wiring by grounding the SCR anode
- Lamp always off: trigger the SCR gate from TP3
- Lamp always on: ground the SCR gate from TP2
- LEDs flicker in controlled lamps on Bally and Stern SCR lamp boards
- No GI at all: failed Q14 SCR on the main lamp driver board
Source: Repairing Bally Electronic Pinball Games from 1977 to 1985, Part Three, Clay Harrell (pinrepair.com)