Well today's cell phones are still using 800mhz, the only difference is that
they are digital. But they use analog to fall back on when they can't find a
good digital signal.
The PCS and tri-mode cellular phones use both the 800mhz cellular band in
digital,analog and also have
the ability to go to the PCS band which is 1.6-2.0ghz.
All PCS is digital, where cellular is not.
The 9000's had two different sets of serial#'s. And from I understand there
are slite differences in the units.
I'm not sure if it was software or RF.

Lou