Phone, frequency, hell

My selection of getting my next mobile in Hong Kong and then bring it back to US to use in either AT&T or TMobile network is getting smaller and smaller.  But the reserach forced me to understand all options I have now, and that is actually a good thing.

So it started with me finding out that AT&T operated at a 3G Data Frequency (850/1900), and in fact use 850 in most area since it's the original and better equipped frequency.  My HTC Desire brought from Hong Kong does not operate at that frequency and so I cannot use my HTC Desire with AT&T's 3G data network.


So now, with the TMobile $30 unlimited 3G no-contract data plan, I was thinking, how about T-Mobile.  Sure, many people have shitty experience, the activation seems to require IMEI, but I was told that there are people successfully worked around the problem to use the plan.  And since the kit is so cheap, I was thinking that maybe it worth the try, PROVIDED that the TMobile phone frequency works with my HTC Desire.


So here's what I found out: nope.


Here's what I got from this link: "T-Mobile uses a specific kind of frequency calls AWS and it's the 1700mhz band, if the phone just has 2100mhz it will not receive any kind of 3G signal whatsoever."  Another link confirms that it does use 1700.  This post explains further about the fact that even if a phone supports 2100, which TMobile use, but since "TM splits its downstream/upstream services for 3/3.5/4G between 1700 and 2100 mhz. If you have a phone with just 2100 it won't work."   So that means a phone needs to either use 1700 or have both 1700 and 2100 in order to work on TMobile's 3G data network.


Becasue of that, not only my HTC Desire won't work on TMobile, the international version of Samsung Galaxy S II also won't.    notice that they have 1700 only for special version "(For Telus)". How about Note?  International version, NO CHANCE.  All thanks that freaking 1700.  Now I was told that Tmobile is working on it SO THAT they can support iPhone.  But I'll wait til that actually happens.

So TMobile is out of the picture.  On the bright side, most recent phones like Samsung Galaxy Note, Samsung Galaxy S2 and so on supports AT&T's 850/1900 frequently.  So I guess I just have to stick with AT&T for a while then.