Randie,
I'm working on that now,
check out           http://www.leadtek.com.tw
for a good low cost GPS receiver that uses the SiRF Technologies chipset.
The output is a NEMA 0183, basically RS-232 at 4800 baud (5V too)

accuracy is 100m with out the differential antenna...

Cost is about $150 for 1 unit to around $85 for 10K units

location is by position from  a series of 24 satellites that orbit the
earth,
for more detailed info than that go to Amazon.com and order "Understanding
GPS
principles and applications" by Elliott D. Kaplan (recommended for engineers
only)
Hope this helps
Jason


-----Original Message-----
From: Randie Ohtsji [4555] <rohtsji@GLENVAN.GLENAYRE.COM>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Tuesday, December 09, 1997 2:36 PM
Subject: gps


>Hello,
>
>I am interested in more information on GPS.  Does anyone have any good
>links?
>
>Questions:
>
>        1) Has anyone interfaced a gps receiver with a pic before?
>        2) Source of low-cost gps receivers?
>        3) How accurate are they?
>        4) How do you interpret the data and calculate your location?
>
>Any information would be appreciated!
>
>-Randie
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