>-----Original Message-----
>From: Dave VanHorn [mailto:piclist-bounces@mit.edu] 
>Sent: 18 May 2005 22:54
>To: Microcontroller discussion list - Public.; Microcontroller 
>discussion list - Public.
>Subject: RE: [EE] Detecting vehicles by magnetism
>
>
>Then there's the TX-RX method, send 1kHz into one coil, and use 
>another to pick it up, using synchronus boxcar detector integrator if 
>need be, to eliminate noise.  Level shifts tell you that the amount 
>of magnetic coupling has changed.
>

Developing this idea, how about the other metal detector methods such as
BFO or pulse induction?  Pulse induction in particular can achive pretty
good ranges.

Regards

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
information contained in it may be confidential and/or protected by
law. If you are not the intended recipient of this message, you must
not make any use of this information, or copy or show it to any
person. Please contact us immediately to tell us that you have
received this e-mail, and return the original to us. Any use,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist