Reference http://www.4qdtec.com/mvibs.html. I have been pondering how does the author claims the period for each state in the multivibrator comes to 0.69CR. So for the entire cycle for on - off f = 1/T. Which is understandable. T = t1 + t2 t1 = 0.69CR t2 = 0.69CR....... I have no clue how the author comes out which this magic value. Shouldn't it be 5CR instead of 0.69CR? Not sure here.... Thanks, John ____________________________________________________________________________________ Any questions? Get answers on any topic at www.Answers.yahoo.com. Try it now. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist