FW: [aprssig] solutions for indoor tracking

Keith Kotch kkotch at earthlink.net
Thu Jun 2 06:51:55 CDT 2005

The anti-theft security devices at the doorways at Wal-Mart, Lowe's and Home
Depot work more than mere inches away.

Longer range devices are the EZPass type automatic toll devices.  We've had
some normal high speed lanes opened up here in the Orlando area on some of
the toll roads and those readers are in the neighborhood of 15 feet above
the roadway.

Keith, KF4BXT

-----Original Message-----
From: aprssig-bounces at lists.tapr.org [mailto:aprssig-bounces at lists.tapr.org]
On Behalf Of Wes Johnston
Sent: Wednesday, June 01, 2005 5:00 PM
To: TAPR APRS Mailing List
Subject: [aprssig] solutions for indoor tracking

In the past couple of days, a few suggestions have come forth.... This
is just me thinking aloud.

2)Jim Lux suggested that we put the smart in the digipeater.  If a
digipeater sees a position that is invalid (ie GPS signal unavailable),
it would substitute a valid position.  This gets back to 1998 when
everyone did indoor BOXn-n tracking at Dayton.  You use a really deaf
radio like the MFJ data radio and make it even more deaf by clipping the
PIN diode.  It can then hear a D7 from 20 feet away at 5 watts.  Problem
is, today, we have pocket trackers that put out .25watts, and would be
heard only inches away.  

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