Herbert, Just a small point... On Wed, 26 Jan 2005 00:18:30 -0500, Herbert Graf wrote: > Laser diodes transmit a VERY narrow band of frequencies. If it is a genuine laser, it's transmitting a *single* frequency, I believe! :-) Cheers, Howard Winter St.Albans, England -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist