Found this while hunting for a Tokin Gyro circuit (which I know I saw somewhere!) "Linear Pitot-Tube Air-Speed Indicator" http://www.elecdesign.com/Articles/Index.cfm?ArticleID=946&Extension=pdf Scott -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu