We can not go cross the track, (not allowed), We can't go down the track either, however, using sound is interesting, we have another project really need to sue sound, so we would like to try that out. -- Youda On Tue, Oct 26, 2010 at 8:23 PM, YES NOPE9 wrote: > Are you allowed to put a reflector on the far side of the tracks and boun= ce a laser off the reflector ? > Gus > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .