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I'm thinking about buying an unlocked Vibrant to use on AT&T, will the 3G work on AT&T network? Thanks.
Yes utilizing UMTS Band II 1900 MHz
lqaddict said:
Yes utilizing UMTS Band II 1900 MHz
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Actually, the rumor going around the internet that you can only use At&t 1900mhz on the Vibrant is false.
The vibrant can also utilize wcdma 850mhz. So you should have no problems picking up both 3G signals from At&t.
I will work on making a how to video that shows how to make the vibrant pick up the wcdma 850, takes litterly 2 minutes to do.
Remember, you might run into other annoying problems such as setting up visual voicemail to work with At&t.
SamsungVibrant said:
Actually, the rumor going around the internet that you can only use At&t 1900mhz on the Vibrant is false.
The vibrant can also utilize wcdma 850mhz. So you should have no problems picking up both 3G signals from At&t.
I will work on making a how to video that shows how to make the vibrant pick up the wcdma 850, takes litterly 2 minutes to do.
Remember, you might run into other annoying problems such as setting up visual voicemail to work with At&t.
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I saw Band V in the service menu, but I had no luck enabling it, so it seems; here in NYC ATT is using UMTS Band II and the Vibrant has no issues picking it up, I am getting upward to 3Mb/s down speeds
Here's an entire thread dedicated to it http://forum.xda-developers.com/showthread.php?t=735461 I was one of the non-believers until I tried an ATT SIM in my unlocked Vibrant.
lqaddict said:
I saw Band V in the service menu, but I had no luck enabling it, so it seems; here in NYC ATT is using UMTS Band II and the Vibrant has no issues picking it up, I am getting upward to 3Mb/s down speeds
Here's an entire thread dedicated to it http://forum.xda-developers.com/showthread.php?t=735461 I was one of the non-believers until I tried an ATT SIM in my unlocked Vibrant.
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Umm interesting thread, similar to what we are doing.
So are you saying you are not able to pick up the wcdma 850 (FDD V) band? We set this up on a friends phone, with his At&t sim, it works.
Can you try setting your phone to wcdma 850 only, and drive to a location that has 850 signal, then check under basic information, you should be getting at&t 850 3g.
vietphunguyen said:
I'm thinking about buying an unlocked Vibrant to use on AT&T, will the 3G work on AT&T network? Thanks.
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Dear Vietphunguyen, there seems to be controversy. We know for certain the vibrant can pick up att 3g signal using 1900 band, but the question is, what about 850. Me and a friend believe the vibrant can also get 850, but that link the other poster provided is something to note also.
Be safe, don't purchase the vibrant yet, until we test this more. 2 make sure you can pick up both 1900 and 850 bands.
I dont know much about the Vibrant just yet, but if its anything like the iPhone on TMO's towers, it might not work. The problem was with ATT using a single band for 3g (1900mhz) to send the recieve but TMO uses 2 bands, 1 to send and 1 to recieve... If this helps at all I dunno! lol
Apexsilverevo said:
I dont know much about the Vibrant just yet, but if its anything like the iPhone on TMO's towers, it might not work. The problem was with ATT using a single band for 3g (1900mhz) to send the recieve but TMO uses 2 bands, 1 to send and 1 to recieve... If this helps at all I dunno! lol
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Thank you, just to clarify, for people visiting this thread.
At&t uses 2 differend 3G bands, one is 1900mhz and the other is 850 mhz. At&t is starting to implement 850 towers. Naturally, you would want a phone that picks up both bands.
Now, we know for CERTAIN, the VIbrant will 100 percent pick up At&t 3G 1900mhz signals. The question is, which we are uncertain of, will the Vibrant also pick up 850mhz band 3G signal, incase you hapen to drive to an at&t area that only has this band.
clearer?
Hello All,
I am on tmobile and had samsung galaxy s before i got SGS2 from at&t (my wife upgraded). i unlocked/rooted the phone after reading through the posts and it worked like a charm!
My concern right now is that I am always on edge data network with tmobile. can anyone help me on this. Tethering is also not much of use when i am on the slowest connection. Please help.
Can't do much about it since AT&T version doesn't support the 3g/4g band for T-mobile.
At&t gs2 doesn't support t-mobile frequency for 3 g.
Sent from my SAMSUNG-SGH-I777 using xda premium
I thought this phone has all the bands to support all networks.
parags1982 said:
I thought this phone has all the bands to support all networks.
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No only AT&T.
My guess is that international version supports all the bands not the carrier branded sgII
^Even international version doesn't support T-Mobile 3g/4g (HSPA+) network.. Not many phones support their network. Or maybe it will.. but not everywhere
AT&T SGSII
2G Network GSM 850 / 900 / 1800 / 1900
3G Network HSDPA 850 / 1900 / 2100
T-Mobile SGSII
2G Network GSM 850 / 900 / 1800 / 1900
3G Network HSDPA 1700 / 2100
International SGSII
2G Network GSM 850 / 900 / 1800 / 1900
3G Network HSDPA 850 / 900 / 1900 / 2100
I am following another post that lets says HOW TO: "Enable 850Mhz 3G Network Frequency on your Samsung i9000 Galaxy S''. will update how it goes... fingers crossed..
parags1982 said:
I am following another post that lets says HOW TO: "Enable 850Mhz 3G Network Frequency on your Samsung i9000 Galaxy S''. will update how it goes... fingers crossed..
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No luck. i read somewhere that i may need to install another modem?
Is there anyone out there with the same issue as mine?
any experts out there?
parags1982 said:
I thought this phone has all the bands to support all networks.
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The AWS (1700) bands are supported only by a handful of carriers. It doesn't exist at all in Europe and Asia. There's little reason for manufacturers to include it on their global phones as so few people use it. It's the reason the T-Mobile SGS2 has a Qualcomm chip instead of Exynos like the rest of them. After the merger, it won't even exist in the U.S. any longer as AT&T plans on using it (1700) for LTE. If you want versatility and the ability to use unlocked phones, change to AT&T.
parags1982 said:
I am following another post that lets says HOW TO: "Enable 850Mhz 3G Network Frequency on your Samsung i9000 Galaxy S''. will update how it goes... fingers crossed..
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In order to get T-mo 3G, a phone must support HSPA on 1700MHz AWS band, not 850MHz. As such, only phones from T-Mo or some Candadian carrier support 1700 band. Rest of the world use 900/2100 for 3G and AT&T uses 850/1900 for 3G/4G.
You are never going to get 3G on T-Mo on any phones from AT&T. Period. Give it up.
foxbat121 said:
In order to get T-mo 3G, a phone must support HSPA on 1700MHz AWS band, not 850MHz. As such, only phones from T-Mo or some Candadian carrier support 1700 band. Rest of the world use 900/2100 for 3G and AT&T uses 850/1900 for 3G/4G.
You are never going to get 3G on T-Mo on any phones from AT&T. Period. Give it up.
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thanks. i give up
TMobile uses 1700 up, 2100 down. If the handset doesn't support 1700, you are out of luck.
Correct. Many phones support the 2100 MHz International band.
T-Mobile's network is weird though, and uses both 1700 and 2100 MHz at the same time.
My guess is that UMTS1700 support and not 42 Mbps HSPA+ is why the T-Mobile variant of the GS2 is such an oddball phone.
NO AT&T phone and only a small handful of international phones support T-Mobile's 1700 MHz band.
Similarly, only one or two T-Mobile phones (The Vibrant being one of them) support any of AT&T's 3G bands, but none support all of AT&T's 3G bands to my knowledge.
The interesting thing about this entire thing is that if you go into the modem band selection it lists 5 different wcdma bands including the aws 1700. I enabled those bands and tried using a tmo sim but alas it still only worked on edge. It may have just been there cosmetically rather then actually supporting aws bands. use dialer code *#2263# to access the band selection menu. Maybe there is a way to get it to work.
pb1866 said:
The interesting thing about this entire thing is that if you go into the modem band selection it lists 5 different wcdma bands including the aws 1700. I enabled those bands and tried using a tmo sim but alas it still only worked on edge. It may have just been there cosmetically rather then actually supporting aws bands. use dialer code *#2263# to access the band selection menu. Maybe there is a way to get it to work.
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I agree with you and have tried exactly what you did (along with other bands) but still not working.
pb1866 said:
The interesting thing about this entire thing is that if you go into the modem band selection it lists 5 different wcdma bands including the aws 1700. I enabled those bands and tried using a tmo sim but alas it still only worked on edge. It may have just been there cosmetically rather then actually supporting aws bands. use dialer code *#2263# to access the band selection menu. Maybe there is a way to get it to work.
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Typically, the s/w supports multiple versions of h/w. Just because an option's in the menu doesn't mean the h/w's available to support it. The same thing happened with the T-Mobile G2X. It was supposed to be quad-band, the option was in the ROM, but the radio wasn't there to support all the bands.
Ok guys I have an atrix 4g running on t-mobile. My question is why cant I get 4g/3g on this phone ? T-mobile runs on the 2100 band and the phone does support that band so why no 4g or 3g? common sense would tell me that if t-mo runs 4g on 2100 and the phone is capable of running on 2100 that it would work. have searched for a total of about 4 hours or so over the past couple days and cant find a straight answer only thing i can find is that att doesnt run on 2100 band yet the phone does. thanks in advance to anybody that can answer and taking the time to read.
are you getting H+ or H? (This is "3.5g") The Atrix 4g is not a true 4g phone.
Because the 2100 spectrum that you're using the phone on now is part of the quad-band gsm which is edge/2g. The difference lies in the bands used for 3g/4g, in which case AT&T only uses 850/1900 and tmobile only uses 1700/2100.
There is also a bunch of things that include HSPA, AWS, WCDMA, and so on and so on but I don't know enough about that to comment.
EDIT: Also, the only phones I know that can be used on both AT&T and Tmobile 3g/4g are "penta-band" phones like some European Nokia phones and the unlocked Galaxy Nexus that needs to be imported as well.
shattar01 said:
Ok guys I have an atrix 4g running on t-mobile. My question is why cant I get 4g/3g on this phone ? T-mobile runs on the 2100 band and the phone does support that band so why no 4g or 3g? common sense would tell me that if t-mo runs 4g on 2100 and the phone is capable of running on 2100 that it would work. have searched for a total of about 4 hours or so over the past couple days and cant find a straight answer only thing i can find is that att doesnt run on 2100 band yet the phone does. thanks in advance to anybody that can answer and taking the time to read.
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Wcdma=utms=3g
Yes, WCDMA and AWS(1700), as far as I know, are both from UMTS and the differences in regards to 3G between AT&T and Tmobile lie in the spectrum use (850&1900 vs 1700&2100). And both AT&T and Tmobile use HSPA(+) based off their respected UMTS frequencies.
I just don't understand the "leap" in GSM technology that breaks the quad-band compatibility, that's all.
matthew5025 said:
Wcdma=utms=3g
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Also I've read 850 is att's main spectrum for large areas and 900 for T-Mobile. All higher spectrums are for smaller, rural areas.
If your looking for 3g maybe find a town or, buy a dual band amplifier? That's IF they have 2100 MHz band working where you are located.
Lower bands ie 850/900 are the download streams. 1700/1900/2100 are upload streams. If I'm not mistaken
Also a T-Mobile vibrant supports att, it also has our main band, 850mhz. Again which is the main large areas, like T-Mobile 900mhz. 1700-2100mhz for att/T-Mobile range is only as good as the towns that still has that band currently operating for hspa/3g data. I've seen alot of T-Mobile phones that have 850/1900/2100, and work on att. If they were 1600/1900/2100 did not for me.
You need that lower frequencies to ensure it to work. Then....
Also for regional based frequencies...
http://en.m.wikipedia.org/wiki/Universal_Mobile_Telecommunications_System
That link will let you know what that all really means.
I think you are mixing up gsm and umts.
GSM = 2G/Edge
UMTS (HSPA, HSPA+, HSDPA/HSUPA, WCDMA, AWS) = 3G
Have a look here. You will see they label "3G" as "UMTS" which is HSPA/WCDMA. A little more down you can see they label their data as "HSDPA", which is download, and "HSUPA" which is upload. Further delineating the speeds they label either one as UMTS for down and Edge as up, which to me tells me they use gsm for the upload and only use UMTS for download. Either way, there is not a T-mobile phone available that can be unlocked and used on AT&T's 3G, just 2G and vice versa. As I have previously mentioned, you will need a penta-band phone for that.
Ciloteille said:
Also I've read 850 is att's main spectrum for large areas and 900 for T-Mobile. All higher spectrums are for smaller, rural areas.
If your looking for 3g maybe find a town or, buy a dual band amplifier? That's IF they have 2100 MHz band working where you are located.
Lower bands ie 850/900 are the download streams. 1700/1900/2100 are upload streams. If I'm not mistaken
Also a T-Mobile vibrant supports att, it also has our main band, 850mhz. Again which is the main large areas, like T-Mobile 900mhz. 1700-2100mhz for att/T-Mobile range is only as good as the towns that still has that band currently operating for hspa/3g data. I've seen alot of T-Mobile phones that have 850/1900/2100, and work on att. If they were 1600/1900/2100 did not for me.
You need that lower frequencies to ensure it to work. Then....
Also for regional based frequencies...
http://en.m.wikipedia.org/wiki/Universal_Mobile_Telecommunications_System
That link will let you know what that all really means.
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And don't get me wrong, I'm not trying to give anyone a hard time but it's misinformation to tell anyone that a T-mobile phone can work on AT&T 3G.
And I'll say it again, I'm not an expert so if anyone can better explain then I'm all ears (eyes).
live4nyy said:
I think you are mixing up gsm and umts.
GSM = 2G/Edge
UMTS (HSPA, HSPA+, HSDPA/HSUPA, WCDMA, AWS) = 3G
Have a look here. You will see they label "3G" as "UMTS" which is HSPA/WCDMA. A little more down you can see they label their data as "HSDPA", which is download, and "HSUPA" which is upload. Further delineating the speeds they label either one as UMTS for down and Edge as up, which to me tells me they use gsm for the upload and only use UMTS for download. Either way, there is not a T-mobile phone available that can be unlocked and used on AT&T's 3G, just 2G and vice versa. As I have previously mentioned, you will need a penta-band phone for that.
And don't get me wrong, I'm not trying to give anyone a hard time but it's misinformation to tell anyone that a T-mobile phone can work on AT&T 3G.
And I'll say it again, I'm not an expert so if anyone can better explain then I'm all ears (eyes).
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I am just merely stating that I have a motorola defy on ATT, and it worked great for a long time with great speeds before I got a motorola atrix and infuse.
Im not saying that every tmobile phone will have working talk/text, or data for that matter. I have just posted an idea, or atleast what to look for when you are cruising for phones not labeled for your carrier.
I was getting my motorola defy with the att "grand fathered internet" for 10 dollars a month and it was about 160-420KB/s down, and 80-190KB/s up. but some phones are capable of this, others arent. I have a general idea, and have played with several different carrier cellphones and used them with att and att's 3g data.
Rogers HTC Dream (x2 of them)
Telus Milestone
Tmobile Defy
Rogers Atrix
ATT Atrix (x2 of them)
ATT Infuse
Rogers and Telus actually use the same 3G bands as AT&T so as long as those are unlocked they will work. And I'm not saying an unlocked T-mobile can't work on AT&T, because they can (they both use quad-band gsm) but you can not use an unlocked T-mobile phone an AT&T 3G. That's all I'm saying.
Now, they did make an European version of the Defy that uses the 850 3G band but not the T-mobile "branded" one.
I'm going to stick to my guns on this one because I don't want to give anyone the wrong idea about interchanging AT&T and T-mobile phones and expecting 3G service. I'm fairly certain about this and unless someone can prove otherwise that's how I will think.
Ciloteille said:
I am just merely stating that I have a motorola defy on ATT, and it worked great for a long time with great speeds before I got a motorola atrix and infuse.
Im not saying that every tmobile phone will have working talk/text, or data for that matter. I have just posted an idea, or atleast what to look for when you are cruising for phones not labeled for your carrier.
I was getting my motorola defy with the att "grand fathered internet" for 10 dollars a month and it was about 160-420KB/s down, and 80-190KB/s up. but some phones are capable of this, others arent. I have a general idea, and have played with several different carrier cellphones and used them with att and att's 3g data.
Rogers HTC Dream (x2 of them)
Telus Milestone
Tmobile Defy
Rogers Atrix
ATT Atrix (x2 of them)
ATT Infuse
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---------- Post added at 08:47 AM ---------- Previous post was at 08:36 AM ----------
Upon further research, I have found this article, where under certain circumstances, you can use an unlocked AT&T iPhone with T-mobile 3G:
http://www.gsmarena.com/tmobile_usa_running_1900mhz_3g_in_some_areas_iphones_invited-news-3537.php
Now, this shows that an AT&T phone can maybe use T-mobile 3G but not the other way around. Again, I'm always up for learning something new but I need references/proof.
Well I do get att 3g on the defy and vibrant. I am currently getting about 300ish KB/s on them and 600+KB/s on my attic, I'm just going with the facts. Those facts are that certain T-Mobile phones will work with Att, provided they have 850mhz band. That allows you in most towns (near me) to get 3g
False.
300KB/s is Edge speed, which is only 2G.
http://en.wikipedia.org/wiki/2G
http://www.phonescoop.com/glossary/term.php?gid=107
That's why you get faster speeds on the Atrix because it actually uses 3G.
Again, both AT&T and T-mobile use quad-band GSM. Which is why you can unlock a T-mobile phone and use it on AT&T, and vice versa, but it is only 2G/Edge and NOT 3G.
http://www.phonescoop.com/glossary/term.php?gid=139
http://www.phonescoop.com/glossary/term.php?gid=3
Furthermore, here are the wiki pages for AT&T and T-mobile which both inlcude frequency charts outlining the technology (2G or 3G) each one uses:
http://en.wikipedia.org/wiki/AT&T_Wireless
http://en.wikipedia.org/wiki/T-Mobile_USA
Here are the charts:
AT&T:
Frequency Protocol Class
Frequencies used on the AT&T Network
850 MHz GSM/GPRS/EDGE 2G
1900 MHz GSM/GPRS/EDGE 2G
850 MHz UMTS/HSPA 3G
1900 MHz UMTS/HSPA 3G
700 MHz LTE 4G
T-mobile:
Frequency Band Protocol
850 MHz GSM/GPRS/EDGE 2G
1900 MHz GSM/GPRS/EDGE 2G
1700 MHz UMTS (W-CDMA)/HSPA/HSPA+ 4G (formerly 3G[34])
1900 MHz UMTS (W-CDMA)/HSPA/HSPA+ 4G
I check for facts and references, I'm only saying what I find in research.
Again, when unlocked, a T-mobile phone can use AT&T 2G/Edge, not 3G
Ciloteille said:
Well I do get att 3g on the defy and vibrant. I am currently getting about 300ish KB/s on them and 600+KB/s on my attic, I'm just going with the facts. Those facts are that certain T-Mobile phones will work with Att, provided they have 850mhz band. That allows you in most towns (near me) to get 3g
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I have the HTC Radar 4G on T-Mobile. Once I unlock it and use it on At&T, it will definitely do calls, but will it pick up 3G or 4G on the AT&T network? I asked HTC and they were unsure. Thanks!
Do a search in this forum to find your answer.
Sent from my Titan using XDA Windows Phone 7 App
AT&T uses 850 MHz / 1900 MHz for GSM/GPRS/EDGE and the same two frequencies (850 / 1900) for UMTS/HSPA (their 3G/4G service).
T-Mobile uses the same frequencies (850 / 1900) for GSM/GPRS/EDGE, but uses 2100 MHz and 1700 MHz for UMTS/HSPA/AWS (their 3G / 4G network).
If you want to know what phones will work where, compare the frequencies they receive with those of the carrier you want to use.
In the case of the Radar, it uses the following frequencies
GSM/GPRS/EDGE: 850 MHz; 900 MHz; 1800 MHz; 1900 MHz
UMTS/HSPA: 1700 MHz; 2100 MHz
So, for GSM phone calls and data you have a match with AT&T (and, of course with T-Mobile). 3G / 4G is a different story. The Radar has the T-Mobile 3G/4g bands, but not the bands for high-speed data on AT&T.
So, if you are happy just making phone calls and using EDGE data, then you can use the phone on AT&T. If you want 3G /4G as well you have to stick with T-Mobile.
bleh bleh +10
I finally was able to get the h2O SIM card (AT&T service) and surprisingly it picks up 3G! I definitely notice the difference from when it goes from 2G up to the 3G speeds
http://www.htc.com/us/products/radar4g-tmobile?view=1-1&sort=0#tech-specs
Apparently. It says it does 2100/1900/1700/850
*T-Mobile only uses 1700/1900 bands. source
Interesting! I took my specs from the T-Mobile page which omits the UMTS 850/1900 band. Thanks for the correction.
The box clearly states GSM 850/900/1900/2100 AND HSPA/UMTS: 1700/1900/2100
AWS 1700 = T-Mobile, Wind, Mobilicity
UMTS 1900 = AT&T (although they use 850 extensively too), Rogers, Telus, etc
UMTS 2100 = Asia/Europe
My Radar picks up AT&T 3G. Not sure if UMTS 1900 band will be omnipresent on AT&T as a lot have been extended with HSPA 850 as well.
So, whereever you find UMTS 1900, you'll definitely catch AT&T 3G
Hope this helps.
So, will this work with the medianet plan?
z33dev33l said:
So, will this work with the medianet plan?
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YES!! Gets 6M downloads, 1.5M uploads.
I am thinking about trying to get an sgs iii and wondering if it is possible to get it on the $30.00 mo 100min unl data plan through walmart?
I have the exhibit ii on this plan, had it for a couple months, anybody know how I would do this?
If it will work with Tmobile band why not, best to ask the source. I don't think we have a Wal Mart rep guru here.
Sure you can, if you don't want 3G.
Sent from my HTC One X using xda premium
You have prepaid plan, you can put your sim into just about any unlocked GSM phone (and T-Mobile phones) and use it. If you want a good phone right now, get the Galaxy Nexus (GSM), it supports T-Mobile 3G (1700/2100 band). T-Mobile version of SIII will be coming later.
thanks for the responses, a Galaxy Nexus is probably a more realistic option than the sgs3 price wise, going to take a good look at it on the play store.
cheers.
T-Mobile and AT&T both support compatible band.
the SGS3 uses HSDPA 850 / 900 / 1900 / 2100
T-Mobile uses HSDPA 900 / 1700 / 2100
AT&T uses HSDPA 850 / 1700 / 1900 / 2100
now we play match the bands. we see at&t shares 3 bands with the international SGS3, thats great. T-Mobile shares 1, not as awesome, but 1 band is enough.
its true what theyre saying up there about "only having 2G", well i should correct myself, it WAS true. however recently T-Mobile has upgraded their 2100 band to 3G, as theyve been expanding. so it will work fine on Walmart's plan, as they use T-Mobile's network.
T-Mobile will come out with an SGS3 later in the year, for SGS2 it was 6 months behind the international version. the T-Mobile version will use HSDPA 900 / 1700 / 2100. what do more compatible bands mean? well it means if youre in an area you normally wouldnt get good 2100 band signal, you may get 1700 signal. if you live in the city, youll see no difference at all, its only when youre in rural areas.
so in short; you can totally use the i9300 SGS3 on tmobiles network, and yes, you will have HSDPA 3G
soraxd said:
T-Mobile uses HSDPA 900 / 1700 / 2100
now we play match the bands. we see at&t shares 3 bands with the international SGS3, thats great. T-Mobile shares 1, not as awesome, but 1 band is enough.
its true what theyre saying up there about "only having 2G", well i should correct myself, it WAS true. however recently T-Mobile has upgraded their 2100 band to 3G, as theyve been expanding. so it will work fine on Walmart's plan, as they use T-Mobile's network.
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Could really use a source for this, please. Everything i've looked up has suggested that their HSPA+ is only 1700 and 2100, and that phones with only 2100 would not work.
thebobp said:
Could really use a source for this, please. Everything i've looked up has suggested that their HSPA+ is only 1700 and 2100, and that phones with only 2100 would not work.
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you know what, i made a mistake, i was using this
http://support.t-mobile.com/docs/DOC-4261
looking at the bands the T-Mobile One S (along with all other tmobile phones) support, but the 900 band is just added to the phone so it can be used if taken abroad. so my mistake.
to reiterate the sgs3 will only work on 2g on tmobile, it will only work on at&t for 3g.
im glad you questioned it, i would have gone along giving bad information