FOR REVISION
4 BOARDS ONLY
 

Instructions for Installing a Switch to Williams Relay Boards

Before starting: Please be aware that performing this change voids the warranty on the reverse board of this locomotive.

1) Solder a wire from the junction of the 22K/10K resistors (see diagram) to one outside terminal
2) Unsolder and lift inner end of the 100K resistor (see diagram)
3) Solder a wire from the now free end of the 100K resistor to the other outside terminal of the switch
4) Solder a wire from the now vacant hole in the board (hole vacated by inner end of 100K resistor) to the center terminal of the switch.

CAUTION: DO NOT allow switch solder connections to contact metal floor of locomotive.