Develop Bugs

Testing Tmobile with unlocked S3

Hey All,
I've placed a Tmobile sim in my Att unlocked GS3. Ive seen many posts stating that the Att version wont get 4g on tmobile but 4g works fine for me; regularly I can get 5 to 10mb downloads. My issue though is that Im sometimes dropping from 4g to 2g/Edge then back to 4g. Should my phone be dropping to 3g instead ? Im quite shocked when it happens since I usually had strong 4g not far away at all.
Is the general consensus to to simply get a Tmobile device instead of bringing something from at&t? I really dont want to root the phone or flash roms at this point since Im just testing out the service.

goon3r said:
Hey All,
I've placed a Tmobile sim in my Att unlocked GS3. Ive seen many posts stating that the Att version wont get 4g on tmobile but 4g works fine for me; regularly I can get 5 to 10mb downloads. My issue though is that Im sometimes dropping from 4g to 2g/Edge then back to 4g. Should my phone be dropping to 3g instead ? Im quite shocked when it happens since I usually had strong 4g not far away at all.
Is the general consensus to to simply get a Tmobile device instead of bringing something from at&t? I really dont want to root the phone or flash roms at this point since Im just testing out the service.
Click to expand...
Click to collapse
You are in a refarmed market from the sound of it. The reason you go from 4g to EDGE is because the refarmed spectrum is most likely not through your entire coverage area.
T-Mobile uses the 1700 band, which at&t does not support, as their primary 4G deployment. This is why it is always recommended to get a T-Mobile S3.
That said, there is a firmware image for at&t's GS3 that unlocks T-Mobiles AWS band not just for 4G but for LTE as well. It is in the at&t forum - you will have to read the entire thread to get the relevant files and information on how to do it. Note that this CAN brick your phone permanently so only attempt it if you are willing to take that chance and you are familiar with download mode and ODIN.
The upside of using that hack is that the T-Mobile S3 doesn't support LTE at all.
Sent from my SGH-T999

Thanks for the clarification and info about the hack. Assuming I get a Tmobile device, should I expect to see a 3g icon instead or would it still say 4g?

goon3r said:
Thanks for the clarification and info about the hack. Assuming I get a Tmobile device, should I expect to see a 3g icon instead or would it still say 4g?
Click to expand...
Click to collapse
It'll say 4g.. A 4g icon really means 3g/h+ and a 4g lte icon means lte
Sent from my SGH-T999 using xda premium

Thanks!

Here is the link http://forum.xda-developers.com/showthread.php?t=1771021&page=25 Start reading from post #246

[Q] I317 on TMobile Network

Can anyone suggest the best modem to flash on my I317 in order to increase my data speeds using the TMobile Network? If this has already been addressed please excuse the duplicate post.
Thanks!!!
P.S. The person who said "It's not whether you win or lose, it's how you play the game" was a LOSER!!!
JackSch
Galaxy Note 2
Asus TF-201

Jacksch said:
Can anyone suggest the best modem to flash on my I317 in order to increase my data speeds using the TMobile Network? If this has already been addressed please excuse the duplicate post.
Thanks!!!
P.S. The person who said "It's not whether you win or lose, it's how you play the game" was a LOSER!!!
JackSch
Galaxy Note 2
Asus TF-201
Click to expand...
Click to collapse
Good thing is I already been through this. First tou need to use QPST and enable AWS Bands once you do that youll have MMS and 4g. I have done it on CAMA4 and the previous one. I had better service on CAMA4. Have not tried on the new modem. When you upgrade modem you have to enable AWS bands every time. Well atleast for me...hope this helps

QPST Download
G7Baker said:
Good thing is I already been through this. First tou need to use QPST and enable AWS Bands once you do that youll have MMS and 4g. I have done it on CAMA4 and the previous one. I had better service on CAMA4. Have not tried on the new modem. When you upgrade modem you have to enable AWS bands every time. Well atleast for me...hope this helps
Click to expand...
Click to collapse
Thanks so much for your response. Would you have any suggestions on where I can locate this QPST tool?

What's your location? I've gotten pretty good speeds and coverage on a non modded i717 in refarmed Chicago, even a few spots of LTE.

I was using stock rom with stock radio UCAMA4 and was able to get hsapa since I am in the refarm 1900 region. Today, I just noticed that I am getting LTE speed. The spee is decent with 12 down and 6 up. Not blazing speed but good enough for me.
haven't tried new modem yet.

Location
bob60626 said:
What's your location? I've gotten pretty good speeds and coverage on a non modded i717 in refarmed Chicago, even a few spots of LTE.
Click to expand...
Click to collapse
I am primarily in Rockland & Orange Counties of NY. As an update I was able to download the Qualcomm tool and adjust the AWS files using a video I found. Also did an NV backup. I am now receiving HSPA & HSPA+ when I used to get EDGE in a much wider geographic location then before.
A broader issue is that TMobile has not focused on rolling out 4G in the more suburban areas of NY. As I am not tied to a contract I can try AT&T and see if I fair better. Since there are a ton of WiFi locations that Cablevision provides I do get by.
Thanks for the input!!!!

[Q] Galaxy s3 att unlocked.. All ROM show 3G

Hi i have Galaxy s3 ATT i747 unlocked and every ROM i install give me 3G.. If i leave stock ROM it gives me 4G with know problems.. Is there any fix i can do that will give me 4G and modem i can install. Im on tmobile network

Can you see your IMEI number? I lost mine while flashing roms and the network couldn't recognize my phone, so it booted me down to 3g (but I'm on ATT).
jamiefff said:
Hi i have Galaxy s3 ATT i747 unlocked and every ROM i install give me 3G.. If i leave stock ROM it gives me 4G with know problems.. Is there any fix i can do that will give me 4G and modem i can install. Im on tmobile network
Click to expand...
Click to collapse

Ozark_8125 said:
Can you see your IMEI number? I lost mine while flashing roms and the network couldn't recognize my phone, so it booted me down to 3g (but I'm on ATT).
Click to expand...
Click to collapse
Yes I can see my imei
Sent from my SGH-I747 using xda app-developers app

Do your roms have the correct apn's?

I'm having connectivity challenges when trying 4.2.2 roms on Rogers w/ my i747m.
Tried most of the recommended modems on for i747m (complete modem list) http://forum.xda-developers.com/showthread.php?t=1831898
with CM10.1 and AOKP Task650.
The result, at worst little to no connectivity, at best intermittent connectivity. It doesn't seem to want to switch between towers and getting connectivity better than gprs or edge is pretty much non-existent
When I burn the rooted Rogers ROM - root66_RWC_I747MVLDLK4.tar.md5 I get good connectivity switching and 3G. I haven't seen LTE yet but it was only officially rolled out here 9 days ago so it's still crap and only partially out.
I'm about to roll back to the rooted ROM and apply the latest Canadian patch via KIES and give up on S3 mods. If some kind canadian has the time or inclination a faq/step by step on a S3 rogers install that actually works would be very appreciated. I've tried most of the recipes on XDA, task650, cyanomodgen and can't seem to come up with a working combination that gives me data/phone service that is at least as good as stock.
thanks,
rf

jamiefff said:
Hi i have Galaxy s3 ATT i747 unlocked and every ROM i install give me 3G.. If i leave stock ROM it gives me 4G with know problems.. Is there any fix i can do that will give me 4G and modem i can install. Im on tmobile network
Click to expand...
Click to collapse
This may be correct. Do other ROMs switch between 3G and H+? Do you see 4G vice 4G LTE on stock rom? What download speeds are you getting on stock and other ROMs? With AT&T, HSPA was labeled 4G instead of H or H+. They had to add LTE to the 4G after LTE went online for them in order to differentiate a difference. The majority of places have HSPA labeled as H or H+ and LTE is considered true 4G. I have noticed that many ROMs will show 3G until data is received/sent and it switches to H+.

Tmobile note 3 slow lte on att

Just made the switch over to att and I am getting really slow lte speeds. Can anybody help?

Fix your APN?
sent from my sm-9005.

@rbiter said:
Fix your APN?
sent from my sm-9005.
Click to expand...
Click to collapse
Tried every APN setting possible already. Searched all the threads and still no help.

There's a thread on here about flashing the AT&T modem and it solving the problem. Plz search and find it...
Here I found it for you..
http://forum.xda-developers.com/showthread.php?t=2522282
Sent from my SM-N900T using XDA Premium 4 mobile app

AdmiralCF420 said:
There's a thread on here about flashing the AT&T modem and it solving the problem. Plz search and find it...
Here I found it for you..
http://forum.xda-developers.com/showthread.php?t=2522282
Sent from my SM-N900T using XDA Premium 4 mobile app
Click to expand...
Click to collapse
Thanks for the advice but I read through the thread already and it doesn't seem like it will improve drastically. So I rather not attempt to flash a modem that may cause a soft brick. My brother has a N900a and gets almost triple the speed of my lte. What gives?

I dont always get fast speeds. I'm guessing at&t phones get higher priority than other phones. There is a build.prop that you can flash/edit that may or may not work. I, myself, haven't made any mods because I get higher speeds usually. Not always. I am on a 900T but using an international 9005 rom with T-Mobile modem still. It really boils down to is the risk flashing a modem or build.prop worth it. In downtown houston I rarely dip below 10mb/s on LTE and occasionally see over 20mb/s. The congestion is real bad here so it is very often I get bumped back down to hspa. Like I said, you have to weigh the risks. I am fine with how it is working now. My post probably hasn't helped you get you where you want to go but it may help you to be content with what you have or may consider flashing an international rom minus modem and see if that helps.
sent from my sm-9005.

I'm on straight talk att sim and it's ridiculous on an att phone I get att quality signal. But with this tmobile phone when home I can only get signal in my bed room by the window . From I walk into building calls and signal dropped dead . It truly sucks. I'm switching back to tmobile as soon as this month is over . I hate paying that extra 30 dollars but a phone is no good in one room .
Sent from my SM-N900T using XDA Premium 4 mobile app

diamantericos said:
I'm on straight talk att sim and it's ridiculous on an att phone I get att quality signal. But with this tmobile phone when home I can only get signal in my bed room by the window . From I walk into building calls and signal dropped dead . It truly sucks. I'm switching back to tmobile as soon as this month is over . I hate paying that extra 30 dollars but a phone is no good in one room .
Sent from my SM-N900T using XDA Premium 4 mobile app
Click to expand...
Click to collapse
I as well am on Straight Talk At&t micro sim and I get pretty decent speeds I believe Straight Talk cap's their LTE speeds at 15 down and I think around 8-9 up which ain't bad for the Chicago area. But there are times where I barely get 2 down and 4 up. I also have a Tmobile Note 3 stock/rooted using a ST sim.

nynexelf said:
I as well am on Straight Talk At&t micro sim and I get pretty decent speeds I believe Straight Talk cap's their LTE speeds at 15 down and I think around 8-9 up which ain't bad for the Chicago area. But there are times where I barely get 2 down and 4 up. I also have a Tmobile Note 3 stock/rooted using a ST sim.
Click to expand...
Click to collapse
The speeds are fine when I actually get a signal . Its the fact that I have dead spots in almost my whole apartment except the rooms located to front of building . It was never like this before .
Sent from my SM-N900T using XDA Premium 4 mobile app

Tmobile Note 3 on ATT Network
I have a Tmobile unlocked phone on ATT and I can't find out anyway to speed up the LTE. I get LTE it seems, but it cuts the speed in half compared to my girlfriend ATT variant Note 3. I tried to flash an AT&T modem to it, but then it would soft brick the device and wouldn't boot. I have tried every APN I can think of, but still no success. I have tried the build.prop, like adding the lines for faster data tweak, but still nothing is getting better. I have full bars, but speed is slow. Do you have any suggestions on what to do, b/c I am out of options. Thanks.

Add me to the list. Just switched over to AT&T from T-mobile, but get very bad speeds. The only reason why I switched over was because with T-mobile, I was getting poor quality signal almost EVERYWHERE, so I had no choice.
I'm curious; if the bands in our phones support the proper AT&T bands and we actually get LTE, it's gotta be a software issue. Modem most likely.

Yeah im sure it has to do with the way the modem is optimized for ATT's 1700 band. I'm also in the same boat and have flashed ATT's modem but it doesn't work. Others have flashed ATT modems but I dont think anyone has been able to successfully see their baseband change in the settings so no one can say whether it worked for sure. I can tell you that the bars have nothing to do with your call signal though, its just your LTE signal strength. If you really want higher signal in your house if LTE seems to drop or be super slow, you should manually switch over to use HSPA+ in your house. Its a pain...i know.
I'm hoping eventually the newer modems fix the 1700 mhz frequency optimization or some devs figure out how to successfully flash N900A modems on the N900T.

LTE speeds
I have great signal almost always it seems like. I have full bars on LTE or 4G/HSPA+, but if I put my sim card in my AT&T variant note I get at least twice as much throughput than with the note 3 tmobile. It has to be a software issue, I have tried to flash att modems with no success. Just got to wait for a tweaked modem. I have even tried tweaking build.prop file and it works a little bit but not much. It is just weird I have full bars with LTE, but I won't be able to get data sometimes, which is really weird. I think there has to be something with the signal bars showing higher dbm that it actually is receiving. Probably another software glitch. Well if anyone has any insight on this issue let us know, please been looking everywhere.

LTE speeds
I think also that the modem is not the only issue. I flashed a kernel today after being on the stock kernel on the T-Mobile and I did a speedtest and the speeds were really low. Flashed another kernel and boom faster speeds back to where I was, maybe higher, but I will monitor to see what happens. But I read that Kernels do affect data speeds sometimes. I am just going to keep looking around to see if any kernels work.

stevestebo said:
I think also that the modem is not the only issue. I flashed a kernel today after being on the stock kernel on the T-Mobile and I did a speedtest and the speeds were really low. Flashed another kernel and boom faster speeds back to where I was, maybe higher, but I will monitor to see what happens. But I read that Kernels do affect data speeds sometimes. I am just going to keep looking around to see if any kernels work.
Click to expand...
Click to collapse
AFAIK it has nothing to do with kernel I might be wrong its just the modem
Sent from my SM-N900T using Tapatalk

Steven
Is there any tweaks that can be done to kinda help the LTE or at least fix my signal bars showing full all the time. I am thinking it is not switching towers when it is supposed to and giving a false signal strength. Is there anything on modifying like you can on Sprint phones with dbm on wimax, where it will switch antennas.

Has anybody flashed the new N900T NE6 based ROMs / modem and seen any difference?

dirrtyswan said:
Has anybody flashed the new N900T NE6 based ROMs / modem and seen any difference?
Click to expand...
Click to collapse
I upgraded the modem and bootloader to the new NE6 version. I'm on Temasek CM11. My observations:
Signal strength is slightly better. Speeds are definitely much better. Prior to the upgrade, I'd get around 6-15/down, 3/up. Now I consistently get 25/down, 10/up.

ajm786 said:
I upgraded the modem and bootloader to the new NE6 version. I'm on Temasek CM11. My observations:
Signal strength is slightly better. Speeds are definitely much better. Prior to the upgrade, I'd get around 6-15/down, 3/up. Now I consistently get 25/down, 10/up.
Click to expand...
Click to collapse
How did you get the new modem to stick? Did you do the triangle away method? If so, did you have to revert to a stock kernel first? I'm trying to upgrade only the modem and leave the bootloader as is. Is that a bad idea?

dirrtyswan said:
How did you get the new modem to stick? Did you do the triangle away method? If so, did you have to revert to a stock kernel first? I'm trying to upgrade only the modem and leave the bootloader as is. Is that a bad idea?
Click to expand...
Click to collapse
It's getting incredibly frustrating to have to repeat this a number of times. I think this morning I had to repeat it already 3 times. Please do a search; there are plenty of pointers on how to get it done. For reference, here is what I did.
http://forum.xda-developers.com/showpost.php?p=52904005&postcount=95

Unlocked AT&T S3 I747 for MetroPCS/TMobile

Has anyone here bought an unlocked AT&T S3 to use on the MetroPCS/Tmobile network? If so has there been any issues? shorter battery life, bad connectivity?
I am debating getting the S3 unlocked or HTC One S. I would prefer the HTC One S but it doesn't have microSD slot

I have a SGH T999 Lte at&t branded unlocked and use on TMobile with the T999L lte rom with no ill effects.
Sent from my SGH-T999L using XDA Premium 4 mobile app

afwolfpacked said:
I have a SGH T999 Lte at&t branded unlocked and use on TMobile with the T999L lte rom with no ill effects.
Sent from my SGH-T999L using XDA Premium 4 mobile app
Click to expand...
Click to collapse
Is that the same model as my phone? So it would be advisable, after I got the S3 to flash it with a MetroPCS ROM after activation by Metro?
I thought there would be no need of a flash if I got an unlocked phone.

edo101 said:
Has anyone here bought an unlocked AT&T S3 to use on the MetroPCS/Tmobile network? If so has there been any issues? shorter battery life, bad connectivity?
I am debating getting the S3 unlocked or HTC One S. I would prefer the HTC One S but it doesn't have microSD slot
Click to expand...
Click to collapse
You will have issues with 3G HSPA+ on 1700mhz, but 2G EDGE & 4G LTE will work just fine. If you live in a large metro area with a lot of LTE coverage it will be fine. I just went through this with my wife's phone, she had to have the Red one (AT&T specific).
edo101 said:
Is that the same model as my phone? So it would be advisable, after I got the S3 to flash it with a MetroPCS ROM after activation by Metro?
I thought there would be no need of a flash if I got an unlocked phone.
Click to expand...
Click to collapse
There is no need to flash anything, just unlock it and add/edit the APN for TMo.

DJ_SpaRky said:
You will have issues with 3G HSPA+ on 1700mhz, but 2G EDGE & 4G LTE will work just fine. If you live in a large metro area with a lot of LTE coverage it will be fine. I just went through this with my wife's phone, she had to have the Red one (AT&T specific).
There is no need to flash anything, just unlock it and add/edit the APN for TMo.
Click to expand...
Click to collapse
Sweet thanks! Both areas that I frequent have 4G and LTE coverage. My only concern is when I'm driving long distances which I often do, being in college and losing 2G signal in the middle of no where. So far with my Metro phones, I haven't seen anywhere I had 3G coverage. its always 2G and 4G/LTE

edo101 said:
Sweet thanks! Both areas that I frequent have 4G and LTE coverage. My only concern is when I'm driving long distances which I often do, being in college and losing 2G signal in the middle of no where. So far with my Metro phones, I haven't seen anywhere I had 3G coverage. its always 2G and 4G/LTE
Click to expand...
Click to collapse
Good, that is exactly what we are seeing as well. Mostly LTE coverage with EDGE to fallback on. Most all Metro areas and major highways/interstates will have good coverage. Funny enough we live in the middle of nowhere, but there is a major highway nearby so we get LTE coverage.
On a side note, US carriers marketed HSPA as 3G and HSPA+ as 4g, but both are technically 3G. True 4G is LTE. I am not sure if Metro ever had HSPA service, I think that they were just CDMA then later added LTE and have been migrated to TMo's GSM/HSPA network which now uses Metro's LTE as well. Only the newer GSM Based phones would connect to HSPA.

I have my s3 i747 unlocked an on metro I cannot get no data

banks2878 said:
I have my s3 i747 unlocked an on metro I cannot get no data
Click to expand...
Click to collapse
Check your APN settings.

i cant even get to the apn's when i goto more network then mobile networks it says insert Sim card to access network services but calling an text work fine

banks2878 said:
i cant even get to the apn's when i goto more network then mobile networks it says insert Sim card to access network services but calling an text work fine
Click to expand...
Click to collapse
What firmware are you running?
Sent from my SGH-T999 using Tapatalk

4.3 rooted.. I got data now that I flashed a modem but its very slow datai don't know how to find the right 1..heres what the one I downloaded is called modem_CWM_I747UCUEMJB

Define Slow data please. Post Speed test results.

normally around 0.15mbs but sometimes it works great and I get around 15.00mbs

Given this is not an LTE device, that sounds about right. Weather, tower congestion do affect results.

Perseus71 said:
Given this is not an LTE device, that sounds about right. Weather, tower congestion do affect results.
Click to expand...
Click to collapse
The I747 is an LTE device, my wife's (running on TMo) works just fine on LTE, just not HSPA+ 1700MHz. I'll run speed test if people would like.

Unlocked att siii will not access metro/t-mobile data
Can someone verify for me what the correct apn settings are? Should there be a network operator? And since I think the apn is finally right, do you have any more suggestions? Also, do you know if this is CDMA or GSM?

can I ask why people want to buy an ATT phone to use on a Tmobile carrier? On the S4 and Note versions, people buy Tmobile phones and use them on ATT, myself included. This is because of the bootloader, and the Tmobile phones cover ATT LTE channels while not the opposite.

Wasn't planned
I didn't intentionally set out to buy an AT&T phone, I was just looking to upgrade and this was the best deal. Or at least it looked to be on the surface. Do I just need to forget it and try to sell it?

If you are in an area recently upgraded by T-Mobile, the I747 will work just fine. However, if you are in an are not upgraded with LTE, etc, it's waay more trouble than its worth. The above post about not getting HSPA+21/42 is worth considering too though.
T-Mobile and AT&T are both GSM networks btw.
Sent from my SAMSUNG-SGH-I747 using Tapatalk

I am actually on Metro P.S, but they are on the T-mobile network now in Atlanta, Ga where I live. We do run 4glte,but so far the fastest mine will connect to shows "E" on my phone, edge maybe? One of the many I've spoken with at metro said E is 3g. One of their repair techs said I needed a different SIM card because I had a CDMA phone but when I got to the store that had one he said it was a GSM phone. It's already about been more trouble than it is worth, but as much effort as I've put into it already, I'd like to resolve it.