If controlled by a Mindstorms RCX, these can be set to one of two colours.
If just attached to a 9V battery box, reversing the switch or the connector
will change the colour.
I know Ken. He's a good guy (and his LED's are good), but he does not post here much. I shall mail him and explain the auction rules. Scott A (...) (23 years ago, 27-Nov-01, to lugnet.trains)
