As Levi explained some cell phones (The Blackberry 8800, for example) have GPS *receivers* built in. The only GPS *transmitters* are operated by the government and most of them are 26,000 miles overhead so it's highly unlikely that a cell phone will ever have one, nor would it ever need it. There are some ground-based transmitters used for more precise and quick locating but that's an add-on to GPS, DGPS, and most phones don't pick those up.
There was a 911-related requirement that all phones be locatable and, as I understand it, the manufacturers were going to put GPS receivers in all phones but they they hit on the idea to use the nearest cell tower's location and that got around the GPS requirement. With a solid lock on more than four GPS satellites you can determine your location to within 3-5 meters. Using the cell tower the best I've seen is 300 meters, but usually it's more like 1000-1500. I'm pretty sure when you call 911 the phone locks onto two towers to determine your location much more accurately. However, doing that all the time would tie up twice as many cell channels which is why the cell carriers won't allow that to be enabled all the time. On Sun, 27 Jan 2008, ppsn168 wrote: > Are you saying there is (by law) a GPS transmitter, but no receiver? > > --- In [email protected], Levi Wallach <[EMAIL PROTECTED]> wrote: >> >> Yes, but you need an external GPS. There's no GPS receiver in the > 700wx. >> >> >>> -----Original Message----- >>> From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of >>> ppsn168 >>> Sent: Sunday, January 27, 2008 11:46 AM >>> To: [email protected] >>> Subject: [Treo] 700wx GPS puzzle >>> >>> I recently download Google Maps to the 700wx and got it displaying >>> favorite addresses properly. Nice tool! >>> >>> One of the "Menu" items for this program is "Track Location", which is >>> supposed to fire-up the GPS and figure out where the phone is. Mine >>> tells me "Your GPS receiver does not appear to be responding." I even >>> took it to the local Verizon store for assistance and they failed to >>> get it working. Tech support has indicated that there is some >>> security issue with Google Maps which Verizon choose not to deal with. >>> >>> Has anyone gotten this feature to work, and how? >>> >>> >>> >>> >>> Yahoo! Groups Links >>> >>> >>> >> > > > -- -Jason ----- --- There are no absolute statements. I'm very probably wrong. --- "The difference between genius and stupidity is that genius has its limits." - Albert Einstein
