Stipulated:
1. N97 has the US ATT 3g frequencies.
2. It does not have the US T-mo 3g frequencies.
3. Radios frequencies in handsets are independent of the sim inserted.
Today I visited a real Tmobile store in an area that has Tmobile 3G AND ATT 3G. I showed the guy my two handsets (N97 and Nexus) and inserted the ATT chip in the N97. It grabbed the ATT frequency no problem. I inserted the Tmobile chip in the Nexus, it grabbed the T-mo 3G signal no problem.
So, I have now established that the Nokia can get the ATT 3G signal and the Nexus can get the Tmobile signal. I have also shown that I have data provisioned on both sim cards.
Then I took the Tmo chip out of the Nexus and put it in the N97. I went to the phone settings and told it to scan for service providers in the area. After a while it told me that there were signals from T-mo and ATT in the area. I told it to connect to the ATT signal. As he was watching me do this, the T-mo guy behind the counter said "This is not going to work". He was right, the phone gave a message saying something like "Your sim is not authorized for use on this network". Then I told it to connect to the T-mo network and it connected fine. No 3G, of course. (Because the N97 does not have the radio to connect to the USA T-mo 3G frequencies)
I asked him several questions:
1. Will the sim not connect to ATT because there is a T-mo signal in the area? Answer: Yes
2. When I am in an area where there is no T-mo signal, but there is an ATT signal, will the T-mo chip EVER connect to an ATT 3G signal? Answer: No, never.
3. So, are you telling me that there are T-mo customers all over the USA who are unable to roam onto ATT 3G networks, no matter what phone they have? Answer: Yes
So there you have it folks, yet another argument for a complete overhaul of the antiquated, backward, stupid, sclerotic, siloed US mobile phone system.
