Hey,
As I understand it, it all depends on where you are.  I've been
trying to learn all this stuff myself over the last several months
before switching over from TDMA to get, in particular, better data
services.  Cingular and AT&T hold licenses for both the 1900 MHz and 800
MHz (aka 850) spectrums, but not necessarily in the same places.  For
example, Cingular may own 800 spectrum in city A and 1900 spectrum in
City B.  T-Mobile, as I understand it, only operates on 1900 in the US -
has no 800 licenses at all.  The 900 Mhz and 1800 Mhz GSM systems are
non-US and, for the most part, non North America.  Many of the GSM
phones are 900, 1800, 1900.  So, they operate internationally and on the
1900 MHz band in the US.  BUT, they will not operate at all on the 800
band.  Some are 800/1900 - they will work on all GSM in the US but not
internationally.  There may be 1 or 2 quad band phones now (not sure).
So, if you have a 900/1800/1900 phone, you will not be able to use your
carrier if it's operating on the 800 Mhz band where you are.  For
example, if you are with Cingular and in City B, you're OK since GSM is
on 1900 there and you have a 1900 capable phone.  But, if you go to city
A, you're out of luck.
Scott

"Scott" <noone@hotmail.com> wrote in article
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