Put a magnetic compass beside the wire and send the pulse. If it is working, A magnetic field will be set up and cause the compass to spin. Jim Regards, Jim > -------- Original Message -------- > Subject: [EE] Detecting magnetic pulses > From: David > Date: Tue, September 06, 2011 3:38 pm > To: "Microcontroller discussion list - Public." >=20 >=20 > I am building a very simple magnetic pulse circuit, which sends a short > (1uS) pulse through a coil wrapped round a solid core (using a FET). > This is a near exact copy of a circuit I was given which needed some repa= ir. >=20 > What I don't have is the coil & detector circuit which picked up these > pulses, or a schematic. I know that it is some form of loop (embedded > in tarmac) which feeds into a comparator and then a monostable. Max > distance for picking up the pulses from the transmitter is only a few > inches. >=20 > I'm stuck with the loop part. All I need is something to verify whether > my pulse circuit is working. As my google fu is failing me (though it > does find lots about traffic signals), can anybody suggest how the loop > should work? >=20 > >From the small amounts I've found I think I should be able to do it with > a square "loop" of stranded wire and a resistor and expect a small > voltage out. However I can't find anything more practical than this. >=20 > David > --=20 > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .