To the best of my knowledge, TDMA and CDMA are incompatible.
CDMA has a vastly superior sound quality they say.
Not sure what the sound quality on GSM is like but why couldn't
someone have agreed on a standard for the whole world?
like tv.
There is NTSC (Canada, US and odds and ends of other places)
PAL (Europe and I think Japan) and
SECAM (France and the former USSR).
All have advantages and disadvantages.
NTSC retained compatability with the installed base of black and
white tv sets
through developments in chip technology it got some of the
features of PAL like automatic color setting etc.
PAL retained compatability with the installed transmission
networks of broadcsters but not home tv sets!
SECAM supposedly has better picture quality than the other two
and heaven only knows what it is compatible with.
Oh give me a phone, where the dial tone roams  a 500DR!
Worked for ring tip party or bridged and also for an 8FR.
came in 03 basic black and had the optional G1 handset for the
hearing impaired.
Could be fixed by a 350 pound repairman weilding a quarter inch
flat blade screw driver with bug hands.
If you forgot where it was, you just followed the cord from the
wall!
Now with my flip phone, I have to phone it sometimes to find the
dumb thing.
... RAM = Rarely Adequate Memory
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