----- Original Message -----
From: Scott F. Touchton <Scott.Touchton@US.JDSUNIPHASE.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, February 20, 2001 8:27 AM
Subject: Re: [EE]:Directional transmitter


> You can use pulsed magnetic fields in a wire surrounding the property...
very
> similar to pet containment fences, but with a twist.  Make sure the
magnetic
> field is pulsed DC... otherwise the current flow in the wire is in one
> direction, pulsed on and off to create carrier/modulation characteristics
for
> reception.  Now.. by watching the intial polarity of the voltage signal on
the
> receiving loopstick type antenna, you can tell if you are inside of
outside of
> the wire.

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.

There is something here tho....

How about two concentric 'pet fences'?

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

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