i would not connect it directly to the pic. i would use 2 or 3 transistors between the 'sensor' and the pic pin to get a clean ttl signal and to get electrostatics away from the pic. if you get the first pnp transistor in a collector circuit, connect the base with about 10megs to vcc. then your sensor consists of the pnp's base and gnd. from the collector, you go to the next transistor... i once designed a water alarm for the washing room like that. the whole thing runs about 3 years on a single 9v battery and is very sensitive (alarm goes on if you touch both sensor contacts with your fingers). tino Torben Lund Gesendet von: pic microcontroller discussion list 30.01.03 09:12 Bitte antworten an pic microcontroller discussion list An: PICLIST@MITVMA.MIT.EDU Kopie: Thema: [EE]: waterlevel (on/off) on a PIC pin How can I interface 2 pins of metal to a PIC etc. for detecting waterlevel (on/off)? -the resistance between the 2 pins is several Mohms with water and the circiut is of cource open with no water. /torben -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body