> Tube inside of another tube, insulated from each other, open at both > ends - forms a capacitor Do the tubes themselves also have to be insulated from the fluid (beides each other) being measured? Specifically if the application involves dipping the sensor in a somewhat conducting medium like water? Regards, Anand -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist