If you want to search for the nails then you could play with the CS209A. I
can't remember who makes it but it is ideal for  short range metal
detection -> it'll find those buried wires and pipes also!

John

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body