....But you MUST stick doggedly to the analogies provided until they make sense... A little time spent on Ohm's Law while you're at it won't hurt much. :) The mathematical analogy is a much better description of what actually happens in simple DC circuits. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .