> Given that thermocouples produce electrical energy as long as > the temperature is above absolute 0, then why couldn't one put a few > million junctions in series with each other and get some voltage from > ambient temperature? they don't. they need temperature *difference*. Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: www.voti.nl consultancy, development, PICmicro products docent Hogeschool van Utrecht: www.voti.nl/hvu -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist