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No success in using att galaxy s3 on t-mobile 4g

Hi,
I have been doing a lot of research to try and understand if I can buy a used ATT i747 S3 to use with my t-mobile 4G. I got nowhere so hopefully someone here could help me! Thanks in advance!

I would like to buy a used galaxy s3 to use with my t-mobile 4g. I understand that the bands of the ATT i747 are different than for the T999 s3 version, and i747 has LTE were T999 does not. But doing some research I thought I found a way of making the i747 run 4g on t-mobile with only some simple setting changes.

I found an ulocked i747 s3 and I tried to change the settings on the phone to make it work on 4g. It did not work, it only showed 2g Edge with horrible browsing speed.
I live in Long Island NY 11731 and my current Nokia Lumia 710 was showing good 4G signal.

I have two questions please, so far…

1. Will an ATT Galaxy s3 i747 will work on t-mobile 4g or should I buy T999 only?

2. Will it still be worth buying the i747 over an T999 because in the very near future t-mobile will have the true 4g LTE in my area?

Thanks in advance for all your help!
 
The carrier specific version tend not to have very many hspa bands that they are compatible with. T-Mobile's HSPA mainly runs on the 1700 MHz frequency while some areas have been refarmed to the 1900 MHz. Since you can get EDGE, but no HSPA it sounds like you don't live in one of these refarmed areas. There's nothing you can do about it until your area gets refarmed.
 
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The carrier specific version tend not to have very many hspa bands that they are compatible with. T-Mobile's HSPA mainly runs on the 1700 MHz frequency while some areas have been refarmed to the 1900 MHz. Since you can get EDGE, but no HSPA it sounds like you don't live in one of these refarmed areas. There's nothing you can do about it until your area gets refarmed.

Thanks! How can I tell if/when the 1900MHz band will be available in my area for t-mobile?
 
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Thanks! How can I tell if/when the 1900MHz band will be available in my area for t-mobile?

Because the purpose of the refarming is to free up the 1700MHz frequency for their LTE service, it will most likely be tied to their planned rollout of that. However it's tough to know which areas are getting the LTE upgrade until they start testing it, making it so that there's no way to know until it's essentially done. :(
 
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Looking at the specs for the s3 on att it shows lte in the 700 and the 1700 band, so assuming long island gets lte coverage you should get lte even if no hspa at the moment.


Ok looked at the sensorly maps and at this time long island is not covered.

if its possible take the phone to this area and see if it picks up lte

NY%20lte%20coverage.PNG
 
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Looking at the specs for the s3 on att it shows lte in the 700 and the 1700 band, so assuming long island gets lte coverage you should get lte even if no hspa at the moment.


Ok looked at the sensorly maps and at this time long island is not covered.

if its possible take the phone to this area and see if it picks up lte

NY%20lte%20coverage.PNG

It wouldn't work unfortunately because t-mobile uses aws lte which means it uses two different frequencies, one for uplink and one for downlink. The 1700 is the uplink, but without the 2100 for downlink, it would not be very useful.
 
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Thanks guys. I wish there was a way to know when/if the 1900MHz service would be available in my area... I need to wait on the purchase of the phone for now untill we get more info.

There is this map, where users report areas they have gotten 1900 Mhz service. And it does look like people are reporting that (at least parts of) Long Island has been refarmed, or at least the Western portion has been. While it won't give show you what areas may be covered in the future, it may at least help you know when areas are refarmed.
 
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It wouldn't work unfortunately because t-mobile uses aws lte which means it uses two different frequencies, one for uplink and one for downlink. The 1700 is the uplink, but without the 2100 for downlink, it would not be very useful.
From what I understand of lte, which is not much unfortunately it does not use 2 different frequencies, one for down and one for up.

that is a hspa+ trick to get faster speeds which is one reason att does not have as fast of hspa I believe.
 
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From what I understand of lte, which is not much unfortunately it does not use 2 different frequencies, one for down and one for up.

that is a hspa+ trick to get faster speeds which is one reason att does not have as fast of hspa I believe.

That is the way it is for most lte bands, but aws lte does in fact use two bands. http://en.wikipedia.org/wiki/Advanced_Wireless_Services

Remember, lte is a gsm technology. So follows that aws lte would follow just like aws hspa/umts. This is what t-mobile uses for their LTE and is the only lte the Nexus 4 is compatible with.

You are correct though that the reason AT&T doesn't get faster hspa speeds is because they don't use the aws method. That and congestion.
 
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Looking at the specs for the s3 on att it shows lte in the 700 and the 1700 band, so assuming long island gets lte coverage you should get lte even if no hspa at the moment.


Ok looked at the sensorly maps and at this time long island is not covered.

if its possible take the phone to this area and see if it picks up lte

NY%20lte%20coverage.PNG
thank you for the info, I thought t-mobile band is 1700MHz?

I need to find someone from those areas who can check to see this would work.
 
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thank you for the info, I thought t-mobile band is 1700MHz?

I need to find someone from those areas who can check to see this would work.
tmo's lte is on the 1700. However it looks like most att lte phones have both the 700 and the 1700 because in some att markets they are forced to use 1700 band.

They would not want to release a lte phone that could not use lte in a few of their markets.
 
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So, the AT&T version of the Galaxy S3 (after unlocking) will not get TMobile LTE but will get Tmobile HSPA+ ???

Actually you've got it the other way around tube, LTE works perfectly fine but HSPA+/3G in general (unless you're in a refarmed location) will not work unless you go on XDA and then go to the general section on the "Unlock the 1700 Band for T-Mobile AWS on i747 s3". It was something like that lol it was a thread by sahillz. Do those hacks and you'll be good to go! :thumbup:

You can also see which areas have the band refarmed by checking on a commute to work or college etc.
 
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Actually you've got it the other way around tube, LTE works perfectly fine but HSPA+/3G in general (unless you're in a refarmed location) will not work unless you go on XDA and then go to the general section on the "Unlock the 1700 Band for T-Mobile AWS on i747 s3". It was something like that lol it was a thread by sahillz. Do those hacks and you'll be good to go! :thumbup:

You can also see which areas have the band refarmed by checking on a commute to work or college etc.

Ah OK. Thanks. Thinking about getting a backup to my Note and have been reading on the S3.
 
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Not to be in your business but how much are you going to pay for this S3 . Cause if this phone isnt in good condition isnt worth getting. A new device is better and have better warranty options.

I only buy used phones. I never buy the latest and greatest. If I had the money I would but I don't, so I work within my budget for a good solid used phone that isn't too outdated. I may be selling my GNote and getting a smaller phone but something that can get TMobile's LTE.
 
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