Grave "R"
Matrix column 4, row 2 ·
Wiring
- Column 4
- Green-Yellow J206-4 · U20-15
- Row 2
- White-Red J208-2 · U18-9
Parts
- Assembly B-11696-1
Location
Owner's hint
Stationary target. Check that the blades close when the target is hit and that the diode is intact. (owner's experience, not the manual)
Related
Service log
Everything you record stays on this device.
Service notes: In the switch matrix at column 4 (J206-4, U20-15) and row 2 (J208-2, U18-9). Gap 1/16 inch; clean by pulling card stock through the closed contacts, never a file. One switch that fails T.1 is its gap, the wire at the lug or its diode; a shorted diode makes the whole column or row misread. A whole column dead is U20 or the J206 pin, a whole row is the row comparator. A3 Switches and optos
Appendices:A3 Switches and optosA5 Power driver boardA1 Multimeter basics