> >Only if you know the orientation of the loopstick relative to the wire. >(Just turn around and face the other way and this system will think you are >now outside the wire. Flux within a solenoid is constant across the area, but outside, it falls off rapidly. I'm not sure how well this would work for a really large loop, but it works well enclosing rooms. -- Dave's Engineering Page: http://www.dvanhorn.org Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9 -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu