Can someone send me a schematic or point me to a web site with a schematic of the LED flasher that was made two meetings ago?? I can set up a circuit simulation of that circuit for use in the Spice class. I'll bring a memory stick with the circuit simulation software for install on any computers that don't already have it set up.? Anyone who wants to prepare can download the program here: http://www.linear.com/designtools/software/switchercad.jsp I'll prepare a few circuit files to illustrate a few concepts and mail out links later. MR