Database Users

[Q] SM-G900F (belgium) 4G possibility in USA?

Hi guys, i have an S5 bought unlocked in belgium, europe. I had 4G in europe but in the United States it only receives H+. I checked the supported bandwidths with tmobile usa, two of the bands tmobile uses are in fact also supported by my phone (1800 & 1900) yet still it doesnt work. APN setting are already checked and confirmed correct. Sim card is brand new.
Since it still doesn't work, is there a way to flash a USA rom or upgrade something technical so i can get 4G? I would hate to have to buy a new phone again, i just bought this 4weeks ago thinking it would work globally
Thanks again for recommending the best possible option for me at this point...

Most of your questions here were posed and answered in your other thread.
Your 900F model phone is intended for use in a different country. TMobile uses a 900T model. The main difference between the two is that they support a different set of frequency bands. So just like roaming you could use your 900F phone on TMB, but there will be gaps in coverage. You will be subject to more congestion and dropped calls. And in smaller centers where a limited number of frequencies are in use, you may have no coverage at all.
If you never get LTE in a major center on your unlocked 900F, the first thing to check is that you have a LTE capable SIM and that your carrier i.e. TMB has provisioned your account for LTE. And try installing the latest version of firmware for your phone.
No, you cannot simply flash a 900T firmware onto a 900F and have it transform into the other model. By design, Samsung doesn't allow this (to sell more phones and deter carrier churn). There is a hack to add the AWS band to some models. And several threads endeavoring to expand upon that. However they are nascent and would be best described as experimental, dangerous (a good chance of damaging your phone) and with uncertain results as of this date.
Unless you want to put your phone at risk to be a guinea pig, your options are to live with the imperfect coverage or buy a 900T model.
If you want to take a risk, then have a look at this thread. And here. Basically you could use QPST or mzTools 1.21.a to format an edit NV_RF_BC_CONFIG_l to enable additional LTE bands. Enable the parameters with QXDM, then do the actual write with QPST. And /or try writing a raw image of an LTE enabled variant e.g. 900T baseband to your 900F modem partition with the dd utility. This is experimental. It may do what you want or it may brick your phone.
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ignore - double post

4G 900F in USA
Oké so turns out i am getting 4G just not LTE because of the state i am in. Thanks for trying but what i initially said was correct all S5s are global capable of 4G, just state dependant on the LTE band...

fffft said:
There is a hack to add the AWS band to some models. And several threads endeavoring to expand upon that. However they are nascent and would be best described as experimental, dangerous (a good chance of damaging your phone) and with uncertain results as of this date..
Click to expand...
Click to collapse
That's not quite true. The chance of damaging the phone is extremely small if you follow the instructions.
The thread to unlock all GSM and LTE bands is here.

..

fffft said:
It is true when I'm not quoted out of context. And especially funny that you link to that particular thread to .. prove me wrong?
You didn't realize that the thread you linked to was also authored by me. Funny stuff.
.
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How exactly is that out of context? What important piece of information did I leave out to distort your words? Call bs on that. But yeah I didn't notice that it was your thread I linked to , good job on that thread. :good:

What LTE bands does Sprint HTC 10 have?

I can't find any definitive answers on this. All I know is the minimum is 25, 26 and 41 but it'd be nice to know the full list. I travel internationally and without other LTE bands like band 7, it makes it tough to use it anywhere outside the US.
EDIT: Someone answered this question in another thread but it would be good to get screenshots to verify this.
m03sizlak said:
LTE Bands: 2 / 4 / 5 / 7 / 12 / 13 / 25 / 26 / 41
I've heard that the FCC filings show that the Sprint variant is not capable (tested or approved) for GSM or WCDMA, which is kind of disappointing since I travel a lot in Canada. Any confirmation on this?
Click to expand...
Click to collapse
This list of bands is a little better than both the Sprint variants of the LG G5 and Samsung Galaxy S7. If this phone can be unlocked, you at least have a way to go abroad and use LTE connections in much of Europe and elsewhere. Band 7 is the most common band in the world from what I understand.
I'm curious about this comment about GSM and WCDMA. Hopefully someone can verify this one way or another.

asuh said:
I'm curious about this comment about GSM and WCDMA. Hopefully someone can verify this one way or another.
Click to expand...
Click to collapse
Did you ever get an answer on this? I have a Sprint variant of the 10 and am trying to unlock it as I will be travel for the next 2 years. I've done everything I can think of but cannot get the phone's radio to work with any unlocked ROM. I could use some help here. Any advice or information you can provide?

vijn said:
Did you ever get an answer on this? I have a Sprint variant of the 10 and am trying to unlock it as I will be travel for the next 2 years. I've done everything I can think of but cannot get the phone's radio to work with any unlocked ROM. I could use some help here. Any advice or information you can provide?
Click to expand...
Click to collapse
If you plan to travel outside the US during most of this time, your best options are to sell your HTC 10 and get one of the few unlocked flagship phones on Sprint's networks, assuming you want to stay with Sprint.
Here are your options:
Google Pixel
Samsung Galaxy S7 SM-930U
Samsung Galaxy S7 SM-935U
Nexus 6P or 5X
Motorola X Pure Edition
Apple iPhone
Here's a full list as of February 2017 of radio unlocked phones compatible with Sprint.
There are other unlocked phones that are not compatible with Sprint because CDMA and LTE bands are crippled or missing.

asuh said:
If you plan to travel outside the US during most of this time, your best options are to sell your HTC 10 and get one of the few unlocked flagship phones on Sprint's networks, assuming you want to stay with Sprint.
Here are your options:
Google Pixel
Samsung Galaxy S7 SM-930U
Samsung Galaxy S7 SM-935U
Nexus 6P or 5X
Motorola X Pure Edition
Apple iPhone
Here's a full list as of February 2017 of radio unlocked phones compatible with Sprint.
There are other unlocked phones that are not compatible with Sprint because CDMA and LTE bands are crippled or missing.
Click to expand...
Click to collapse
Thanks for the response. The thing is I'm not on Sprint and have no desire to be. I won't be in the states long. I bought the phone thinking that like most, it could be unlocked and used as needed wherever I travel to. I knew it wasn't unlocked but figured I could do it myself. Well, I've tried a number of times, and keep having an issue with the radio. Can you explain what you mean by bands being crippled? What I'm trying to find out now is whether it's possible for me to get this HTC10 completely unlocked. I think I've done everything right but maybe not. I'm kinda desperate at this point. I love this phone. And if I have to I'll return it and grab another that can be unlocked but I just have a hard time believing that the phone can't be unlocked. It's a strange concept for me. Any help or info would be appreciated.

vijn said:
Thanks for the response. The thing is I'm not on Sprint and have no desire to be. I won't be in the states long. I bought the phone thinking that like most, it could be unlocked and used as needed wherever I travel to. I knew it wasn't unlocked but figured I could do it myself. Well, I've tried a number of times, and keep having an issue with the radio. Can you explain what you mean by bands being crippled? What I'm trying to find out now is whether it's possible for me to get this HTC10 completely unlocked. I think I've done everything right but maybe not. I'm kinda desperate at this point. I love this phone. And if I have to I'll return it and grab another that can be unlocked but I just have a hard time believing that the phone can't be unlocked. It's a strange concept for me. Any help or info would be appreciated.
Click to expand...
Click to collapse
First, go go Google and look up what LTE bands are.
Crippled LTE bands = the hardware inside the phone will not allow certain LTE bands to work unless physically altered. It doesn't matter which ROM you install, you will not unlock all the LTE bands without physical alteration. https://www.quora.com/Does-installing-different-rom-change-LTE-band-frequency
So no, HTC 10 will never be completely unlocked. Look at the list above and buy one of those phones if you want a completely unlocked phone.

asuh said:
First, go go Google and look up what LTE bands are.
Crippled LTE bands = the hardware inside the phone will not allow certain LTE bands to work unless physically altered. It doesn't matter which ROM you install, you will not unlock all the LTE bands without physical alteration. https://www.quora.com/Does-installing-different-rom-change-LTE-band-frequency
So no, HTC 10 will never be completely unlocked. Look at the list above and buy one of those phones if you want a completely unlocked phone.
Click to expand...
Click to collapse
I'm not sure I fully understand. Yes, I know that different chips have different bands that they work with. So, what you're saying is the Sprint HTC10 variant uses either a different chip or has some sort of other hardware configuration that is incompatible with GSM and the wider LTE bands and that no matter what I do with this phone I'll never have a truly unlocked phone? That's what I have understood, so my best option is to send it back. Ok, I get that. But I have read across tons of forums and threads of people who unlocked their Sprint 10s and are able to use them on other non-cdma carriers. So, how does that work? Are all the Sprint 10s the same or are some more limited than others? Are you essentially saying that i would have to get an unlocked/dev edition of the htc10 to be able to use GSM in other countries?
Sorry if i'm asking stupid questions here, I'm just trying to fully understand this. Thanks again for helping me out on this.

If anyone reading this knows better, please feel free to correct me.
This is my understanding of LTE bands and CDMA/GSM radios.
Phones like HTC 10, which are locked, include hardware that are built for specific usages. Prior to HTC 10, HTC phones built for Sprint's CDMA radio were specifically built to lock out GSM radio signals and most other LTE bands using the hardware. This means you'd have to open the physical device and modify the wiring inside the phone in order to allow other signals to work.
As of HTC 10, the locks are supposedly now just software based but I haven't seen proof of that. What this essentially means is that you should be able to unlock the bootloader and flash new Roms that could allow the GSM radio to work universally. However, lots of people are having issues with it. Here's one story of someone who was mostly successful but still had issues:
https://forum.xda-developers.com/showpost.php?p=68960210&postcount=47
Read through the thread above and you'll see a lot of people having issues trying to fully unlock the radios and LTE bands for this phone.
If you ultimately don't want to be on Sprint anyway, I think you really should consider getting something already unlocked that can universally work anywhere. And lots of interesting non-Sprint compatible phones like OnePlus 3t (among the others on the lists I provided) are already unlocked and have a lot of good capabilities and would work great anywhere. The Pixel is one of the best devices out there and the camera is amazing from what most people say.
So I think your options are limited and I'd highly suggest you consider getting a Pixel or something else already unlocked.

asuh said:
If anyone reading this knows better, please feel free to correct me.
This is my understanding of LTE bands and CDMA/GSM radios.
Phones like HTC 10, which are locked, include hardware that are built for specific usages. Prior to HTC 10, HTC phones built for Sprint's CDMA radio were specifically built to lock out GSM radio signals and most other LTE bands using the hardware. This means you'd have to open the physical device and modify the wiring inside the phone in order to allow other signals to work.
As of HTC 10, the locks are supposedly now just software based but I haven't seen proof of that. What this essentially means is that you should be able to unlock the bootloader and flash new Roms that could allow the GSM radio to work universally. However, lots of people are having issues with it. Here's one story of someone who was mostly successful but still had issues:
https://forum.xda-developers.com/showpost.php?p=68960210&postcount=47
Read through the thread above and you'll see a lot of people having issues trying to fully unlock the radios and LTE bands for this phone.
If you ultimately don't want to be on Sprint anyway, I think you really should consider getting something already unlocked that can universally work anywhere. And lots of interesting non-Sprint compatible phones like OnePlus 3t (among the others on the lists I provided) are already unlocked and have a lot of good capabilities and would work great anywhere. The Pixel is one of the best devices out there and the camera is amazing from what most people say.
So I think your options are limited and I'd highly suggest you consider getting a Pixel or something else already unlocked.
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Click to collapse
They are software based. I have unlocked AT&T bands on my Sprint variant, 2 actually , and they worked perfectly fine. I would show you proof but I am back on T-Mobile which the Sprint HTC 10 already has LTE support for by default.

unlock
jblparisi said:
They are software based. I have unlocked AT&T bands on my Sprint variant, 2 actually , and they worked perfectly fine. I would show you proof but I am back on T-Mobile which the Sprint HTC 10 already has LTE support for by default.
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Click to collapse
how did you unlock it manualy? can you show me some instruction?

jacobtvaliashvili said:
how did you unlock it manualy? can you show me some instruction?
Click to expand...
Click to collapse
See my other reply.

Add LTE bands

Hi, I have the xt1687 us model, and I was curious if there was anyway to add band 20 for use in the uk. Thank you.
Edit: forgot add its the unlocked version bought from motorola direct.

Aye aye
Fit like, will try find out 4 u bro

Vwgti83 said:
Hi, I have the xt1687 us model, and I was curious if there was anyway to add band 20 for use in the uk. Thank you.
Edit: forgot add its the unlocked version bought from motorola direct.
Click to expand...
Click to collapse
I wouldn't recommend it - though there appears to be a way (here for the Moto G5, but the process might be similar https://forum.xda-developers.com/g5/how-to/recovering-2g-3g-set-radio-band-to-usa-t3668767 ) you run the risk of setting the incorrect band and require a firmware flash to repair.
Easiest way to look for 4G access is to go to https://willmyphonework.net/ and enter in your device and the destination for using your device. For US devices, it suggests that EE, O2, 3 UK, Vodafone and Virgin Mobile are some of the providers that can provide 4G LTE on alternative bands over here. Please verify this info before considering purchasing a UK SIM for that carrier, if your device is carrier unlocked, or accessing that network if your carrier has a roaming agreement with them.
EDIT - further investigation for O2, at least, suggests that Band 3 support may only be present in London and large cities, and the main O2 signal is 800 MHz (Band 20), so if you're travelling around the UK, might be worth noting. However, O2 and Vodafone appear to be sharing towers, so you may get 4G/LTE signal regardless if you get switched to Vodafone's network. EE seems to have good coverage and uses the other LTE bands supported by the US devices.

echo92 said:
I wouldn't recommend it - though there appears to be a way (here for the Moto G5, but the process might be similar https://forum.xda-developers.com/g5/how-to/recovering-2g-3g-set-radio-band-to-usa-t3668767 ) you run the risk of setting the incorrect band and require a firmware flash to repair.
Easiest way to look for 4G access is to go to https://willmyphonework.net/ and enter in your device and the destination for using your device. For US devices, it suggests that EE, O2, 3 UK, Vodafone and Virgin Mobile are some of the providers that can provide 4G LTE on alternative bands over here. Please verify this info before considering purchasing a UK SIM for that carrier, if your device is carrier unlocked, or accessing that network if your carrier has a roaming agreement with them.
Click to expand...
Click to collapse
Thank you very much for the response, some food for thought, cheers mate!

Yeah, I wouldn't recommend trying this will any newer Moto device... since like 2015. These bands are locked DEEP within the device, and messing with it is potentially hazardous to your device, meaning if you mess up it is possible that you will get no reception on any band or frequency. I don't think I have seen this successfully done since early Moto G LTE & G2 models, and even then there was a lot of bricked devices.
This is not just a firmware, radio software, or tweak that can be done, it involves going deep into the device with Qualcomm provisioning software (which isn't available through any normal channel) and hunt and peck at various undocumented hexadecimal registry options, which often results in no reception or even a bricked device in some cases. This isn't a Nexus 4 that literally had LTE disabled in a simple radio firmware change.
BTW, ignore all those sites that say they can unlock all LTE bands in any Qualcomm device, it will brick your Moto.
Sorry, but your best bet is just get a new device locally. A simple burner phone if your just there on vacation or for a short stay, or invest in a decent device if you plan on being there for any length of time. There are many options for devices in the EU that we don't have in the US and a relatively cheap one could be sufficient for your needs and use your Moto in WiFi mode for other stuff.

Shall I switch A2107G to USA bands?

Hi there. I live in Canada and use A2017G. How to switch it to USA bands and is it safe to do? Or should I wait for Oreo (seems like November)?
Thanks

I think you are stuck with whatever bands that are hardcoded into the G. Probably has something to do with the baseband/radio/modem. I did find an article on XDA awhile back that claims you can add bands to your phone, but it seemed mostly suited toward Samsung. In any case, it doesn't really matter, a G model should still receive a minimum of 4G with most US carriers, but maybe not LTE. I'd imagine Canadian carriers are similar. But I do have to wonder, you live in North America, so why buy a G. The U is the variant that is designed for this region. And U has better support, ROMs, etc.

Maybe you can just flash the A2017U modem

ttkian said:
Maybe you can just flash the A2017U modem
Click to expand...
Click to collapse
Maybe you can avoid suggesting things you clearly have no idea about.
While you're at it, why don't you flash a modem from another phone?
---------- Post added at 05:53 AM ---------- Previous post was at 05:51 AM ----------
evilKabab said:
Hi there. I live in Canada and use A2017G. How to switch it to USA bands and is it safe to do? Or should I wait for Oreo (seems like November)?
Thanks
Click to expand...
Click to collapse
You can't add bands that the phone doesn't have. By changing the daughterboard of an A2017U to an A2017's, a guy simply lost all connectivity, plain and simple. Antenna stuff is hardware stuff.
Oreo won't really add bands either

@Choose an username...: I have read other topics on XDA that say you can use QPST/QFIL to add basebands, on almost any device that has a Qualcomm CPU. But I havent tried this myself. It may just be a matter of placebo, or people wanting to believe that it works, when really nothing may be changing. You could also brick your phone during the attempt, which is part of the reason I havent tried yet.
I think that all A7s have nearly the same hardware, including the same (hardware) modem/radio, but with different basebands enabled/disabled depending on which model you have. But I have no proof of this. I will leave this to people that are willing to deeply dissect the hardware.
And then there are the modem files you can flash, which vary according to your model. I am not sure what would happen if you attempt to flash a A2017G/A2017 modem on a A2017U (or any other combo). I think the worst you will face is a loss of Internet/text/phone calls.
When I first bought my A7 I was going to get the Chinese version from AliExpress, because it has more RAM, storage, and ForceTouch. But then I realized that it doesn't have most of the basebands that my carrier (T-Mobile) supports. And you never know where most of the AE sellers get the hardware, they could be stolen, preowned, whatever. I have bought numerous 'new' items there before, but they ranged in quality, ranging from brand new to fair condition. So I thought better of it and bought a new A2017U from NewEgg, complete with ZTE's Passport warranty and 3 years SquareTrade insurance. And I'm glad I did, since a few months ago I had to make use of that warranty to get my A7 unbricked from DFU, before the tool was available.

I think only differences between A7 models are in processor i.e. bands. There are variants in SD 820.

AnonVendetta said:
... But then I realized that it doesn't have most of the basebands that my carrier (T-Mobile) supports.
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We're in the same boat... My carrier using AWS bands just like T-MO. A2017G was working perfectly fine maybe missing just one band on LTE. And recently new band was introduced - LTE band 13 (700mhz), which supposed to improve indoor reception - big issue for Axon 7 and AWS. They call it 'Extended Rabge LTE.
So A2017U has that band, but A2017G doesnt. My assumption was that both phones are sharing the same hardware and bands available are controlled by software.
I clicked some numbers and got into some engineering menu where I see choices: USA Bands, Cellular 800. So I picked USA and restarted.
EPIC FAIL!
I lost 3g AWS on SIM1! Only 4G present, which is actually working fine. Just imagine phone with perfect 4G connectivity internet is flying, but you cannot place a phone call... (My carrier - Freedom Mobile doesnt have 2G GSM). I tried to switch it back - no luck
Solution - I use SIM2.

Oreo
Just installed it no OTA had to use sd card. That actually fixed SIM1 band problem. It doesnt seem I have band 13 (that is what I wanted), but connectivity seems better and switching between 3g and 4g is very fast...

Questions Re: International (or Latin) unlocked S10+ or Note10+ / T-Mobile

So I am looking to buy an international (or Latin) version of either the S10+ or the Note 10+.
I am on T-Mobile in the U.S.
1. How "bad" will it be if the phone has 3 out of T-Mobile's main bands? It only lacks 71, so what's the impact will be if I don't have band 71 on this phone with T-Mobile?
2. I read in the forum about flashing T-Mobile firmware on unlocked phones. How necessary is it? I prefer not to mess with flashing anything; done it in the past, I am not 'afraid' of it, but I just don't feel like going that route. Will I be missing anything from the T-Mobile network and services if I keep the phone in its stock ROM?
For example: Wifi Calling (important to me), VoLTE, etc. Will I have access to these features if I don't flash the carrier's firmware?
Thank you.

Band 71 is used only in rural areas where cell towers are very far apart . My phones have never used band 71. If you don't know what bands your phone typically is using you can download a free signal app from the Play Store that will show what band your phone is connected to. Unless you live in a very rural area or frequently find yourself in rural areas it's unlikely you need band 71.
Flashing T-Mobile firmware shouldn't be necessary. I don't have the international S10+ but rather the US unlocked model and I get both WiFi Calling and Volte fine without T-Mobile firmware.
I've used many different models of international unlocked phones from Xiaomi and Huawei on T-Mobile and always got both WiFi Calling and Volte to work with only one exception--the Mate 20 Pro. I had to get rid of that phone even though I really liked it because calls kept going to voicemail without the phone ever ringing first.
It turns out that on T-Mobile if your phone supports band 12 it also needs to support Volte or calls go straight to voicemail without ringing if the caller is using Volte . I never had that problem previously because in 5 years of using international unlocked phones the M20P was the first where Volte didn't work on T-Mobile.
There were lots of posts from T-Mobile customers in the XDA M20P threads about calls going straight to voicemail. I haven't read a single post about that issue with the S10+ so it's pretty safe to assume that the international S10+ works fine with Volte on T-Mobile.
Until the S8 Samsung didn't even sell a US unlocked model--everyone in the US with unlocked Samsung phones were using the international models with the Exynos chip and those phones always worked perfectly with T-Mobile which is very BYOP friendly (unlike AT&T).
The only thing you would be missing on the vanilla Samsung firmware is Visual Voicemail but last I checked you could just download the official T-Mobile Visual Voicemail app from the Play Store.
You would also receive your OTA updates from Samsung rather than T-Mobile but that's actually a plus because the unlocked Exynos models receive updates much more quickly than all of the US models including the unlocked Snapdragon models.
Sorry for the very long answer but I wanted to be thorough.
You should be fine with an international unlocked S10+ on T-Mobile. This is a much better phone than unlocked models from Google Pixel and One Plus so I would recommend going for it.
No manual flashing on your part will be necessary.

@jhs39 - Thank you for your extensive response. It is greatly appreciated!
OK, so I mostly use Band 4 with my current phone, which is one of TMB's main bands, so it seems like that indeed the lack of 71 won't be an issue.
However, how do I know if the Int. version will support VoLTE on the TMB network? I can't see anywhere any information about this phone even supports VoLTE (other than the carrier's model of course).
What about Video Calling?
Thanks again.

sbi1 said:
@jhs39 - Thank you for your extensive response. It is greatly appreciated!
OK, so I mostly use Band 4 with my current phone, which is one of TMB's main bands, so it seems like that indeed the lack of 71 won't be an issue.
However, how do I know if the Int. version will support VoLTE on the TMB network? I can't see anywhere any information about this phone even supports VoLTE (other than the carrier's model of course).
What about Video Calling?
Thanks again.
Click to expand...
Click to collapse
If the international model didn't support Volte on T-Mobile there would be posts on XDA complaining about calls going straight to voicemail without the phone ringing. There were multiple threads about that issue in the M20P section but I haven't seen a single complaint about that happening with the S10+.
This phone has been out since early Spring so if there was a problem using the international model with T-Mobile somebody would have reported it by now.
I don’t know anything about video calling though because I use T-Mobile's network via an MVNO and my carrier doesn't offer video calling.

jhs39 said:
Band 71 is used only in rural areas where cell towers are very far apart . My phones have never used band 71. If you don't know what bands your phone typically is using you can download a free signal app from the Play Store that will show what band your phone is connected to. Unless you live in a very rural area or frequently find yourself in rural areas it's unlikely you need band 71.
Flashing T-Mobile firmware shouldn't be necessary. I don't have the international S10+ but rather the US unlocked model and I get both WiFi Calling and Volte fine without T-Mobile firmware.
I've used many different models of international unlocked phones from Xiaomi and Huawei on T-Mobile and always got both WiFi Calling and Volte to work with only one exception--the Mate 20 Pro. I had to get rid of that phone even though I really liked it because calls kept going to voicemail without the phone ever ringing first.
It turns out that on T-Mobile if your phone supports band 12 it also needs to support Volte or calls go straight to voicemail without ringing if the caller is using Volte . I never had that problem previously because in 5 years of using international unlocked phones the M20P was the first where Volte didn't work on T-Mobile.
There were lots of posts from T-Mobile customers in the XDA M20P threads about calls going straight to voicemail. I haven't read a single post about that issue with the S10+ so it's pretty safe to assume that the international S10+ works fine with Volte on T-Mobile.
Until the S8 Samsung didn't even sell a US unlocked model--everyone in the US with unlocked Samsung phones were using the international models with the Exynos chip and those phones always worked perfectly with T-Mobile which is very BYOP friendly (unlike AT&T).
The only thing you would be missing on the vanilla Samsung firmware is Visual Voicemail but last I checked you could just download the official T-Mobile Visual Voicemail app from the Play Store.
You would also receive your OTA updates from Samsung rather than T-Mobile but that's actually a plus because the unlocked Exynos models receive updates much more quickly than all of the US models including the unlocked Snapdragon models.
Sorry for the very long answer but I wanted to be thorough.
You should be fine with an international unlocked S10+ on T-Mobile. This is a much better phone than unlocked models from Google Pixel and One Plus so I would recommend going for it.
No manual flashing on your part will be necessary.
Click to expand...
Click to collapse
That's odd. I'm using a mate 20X and the although it lacks bands 66 and 71 I don't get calls going to voicemail. In fact when viewing my historical phone signal via gsam app, it shows that I always receive a better signal than even the S10+ that I'm currently using. Both devices on T-Mobile USA.
Sent from my SM-G975U using Tapatalk

sbi1 said:
So I am looking to buy an international (or Latin) version of either the S10+ or the Note 10+.
I am on T-Mobile in the U.S.
1. How "bad" will it be if the phone has 3 out of T-Mobile's main bands? It only lacks 71, so what's the impact will be if I don't have band 71 on this phone with T-Mobile?
2. I read in the forum about flashing T-Mobile firmware on unlocked phones. How necessary is it? I prefer not to mess with flashing anything; done it in the past, I am not 'afraid' of it, but I just don't feel like going that route. Will I be missing anything from the T-Mobile network and services if I keep the phone in its stock ROM?
For example: Wifi Calling (important to me), VoLTE, etc. Will I have access to these features if I don't flash the carrier's firmware?
Thank you.[/QUOTE
I have the Hong Kong variant SM-G975 with T-Mobile. No issues with bands, VoLTE. Wifi Calling or 4G, no impact. You won't need to flash the device.
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Click to collapse

varcor said:
I have the Hong Kong variant SM-G975 with T-Mobile. No issues with bands, VoLTE. Wifi Calling or 4G, no impact. You won't need to flash the device.
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Click to collapse
Thanks @varcor . What about Video calling?
BTW - is it 975F or something else?

I use Skype for Video Calling, it works fine. Mine is an SM-G9750, the best price I've seen is on Ebay. The only issue is when you first get the device you'll need to change the language since it's setup in Mandarin. A bit challenging but not a big deal. The Ebay vendor is in Houston which is where the device ships from, only takes a few days.
https://www.ebay.com/itm/Samsung-Ga...im-FACTORY-UNLOCKED-6-4-8GB-RAM-/192846270776

varcor said:
I use Skype for Video Calling, it works fine. Mine is an SM-G9750, the best I've seen is on Ebay. The only issue is when you first get the device you'll need to change the language since it's setup in Mandarin. A bit challenging but not a big deal. The Ebay vendor is in Houston which is where the device ships from, only takes a few days.
https://www.ebay.com/itm/Samsung-Ga...im-FACTORY-UNLOCKED-6-4-8GB-RAM-/192846270776
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Click to collapse
Oh yeah, the legendary Never MSRP.
Sent from my SM-G975U using Tapatalk

Yep, I've bought a number of devices from them, won't use anyone else. Lowest prices, great customer service as well.

varcor said:
I use Skype for Video Calling, it works fine. Mine is an SM-G9750, the best price I've seen is on Ebay. The only issue is when you first get the device you'll need to change the language since it's setup in Mandarin. A bit challenging but not a big deal. The Ebay vendor is in Houston which is where the device ships from, only takes a few days.
https://www.ebay.com/itm/Samsung-Ga...im-FACTORY-UNLOCKED-6-4-8GB-RAM-/192846270776
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Click to collapse
I must the F model. I travel to Israel with a local SIM and they use the F model, and it's the only possibility I have to use their WiFi calling while there. I am not 100% sure it'll work because of firmware but better chances with F model.
Thanks.

Limeybastard said:
That's odd. I'm using a mate 20X and the although it lacks bands 66 and 71 I don't get calls going to voicemail. In fact when viewing my historical phone signal via gsam app, it shows that I always receive a better signal than even the S10+ that I'm currently using. Both devices on T-Mobile USA.
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Not having bands 66 & 71 don't cause the problem with T-Mobile calls going straight to voicemail--if band 12 is supported on a phone T-Mobile assumes the phone also supports Volte and if it doesn't then you get calls going straight to voicemail.
I'm not familiar with the Mate 20X but before the M20P I had a P20 Pro, Mate 10 Pro and P10 Pro and none of those phones had an issue because T-Mobile Volte worked with all of them.
It's also possible the problem with the P20 Pro was fixed after I got rid of the phone since it was a firmware issue that was fixable in a software update . I kept mine for 6 months before throwing in the towel. The only workaround was to turn off 4G in the network settings. With 4G off you would receive all calls since Volte is a 4G function.
I personally love Huawei phones. Hopefully after Trump is gone all of the nonsense with Huawei being barred from using Google apps and bullied out of the US market will go away but they might decide selling their products here isn't worth the aggravation.
I've also used a bunch of unlocked Xiaomi phones on T-Mobile with no issues. A nice feature in MIUI is that if Volte doesn't work out of the box there's a dial code you can enter to manually enable it.
Band 66 is an offload for band 4 when band 4 traffic is high but if a phone doesn't have band 66 it just stays on 4 so not having 66 on an unlocked phone has never caused any problems for me.
Band 71 is only live in parts of the country and is relatively new. It can transmit a signal over unusually long distances and is used to provide cell coverage in rural areas where it would cost too much to build a full network of cell towers.

jhs39 said:
Not having bands 66 & 71 don't cause the problem with T-Mobile calls going straight to voicemail--if band 12 is supported on a phone T-Mobile assumes the phone also supports Volte and if it doesn't then you get calls going straight to voicemail.
I'm not familiar with the Mate 20X but before the M20P I had a P20 Pro, Mate 10 Pro and P10 Pro and none of those phones had an issue because T-Mobile Volte worked with all of them.
It's also possible the problem with the P20 Pro was fixed after I got rid of the phone since it was a firmware issue that was fixable in a software update . I kept mine for 6 months before throwing in the towel. The only workaround was to turn off 4G in the network settings. With 4G off you would receive all calls since Volte is a 4G function.
I personally love Huawei phones. Hopefully after Trump is gone all of the nonsense with Huawei being barred from using Google apps and bullied out of the US market will go away but they might decide selling their products here isn't worth the aggravation.
I've also used a bunch of unlocked Xiaomi phones on T-Mobile with no issues. A nice feature in MIUI is that if Volte doesn't work out of the box there's a dial code you can enter to manually enable it.
Band 66 is an offload for band 4 when band 4 traffic is high but if a phone doesn't have band 66 it just stays on 4 so not having 66 on an unlocked phone has never caused any problems for me.
Band 71 is only live in parts of the country and is relatively new. It can transmit a signal over unusually long distances and is used to provide cell coverage in rural areas where it would cost too much to build a full network of cell towers.
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P20 pro was certified and worked fully on T-Mobile , most devices after that were not.
I don't think my mate 20x connected to band 12, but if it did, then yes it'll probably go straight to voicemail.
Sent from my SM-G975U using Tapatalk

sbi1 said:
I must the F model. I travel to Israel with a local SIM and they use the F model, and it's the only possibility I have to use their WiFi calling while there. I am not 100% sure it'll work because of firmware but better chances with F model.
Thanks.
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The SM-G975F is the Exynos SoC variant for Europe. The SM-G9750 has the Snapdragon SoC and dual SIM's as well. Wifi Calling will work on both devices in any region, including Israel as long as the service provider offers it. The only thing I would recommend is you do some research on Exynos vs Snapdragon SoC's in the S10. Good luck!

varcor said:
The SM-G975F is the Exynos SoC variant for Europe. The SM-G9750 has the Snapdragon SoC and dual SIM's as well. Wifi Calling will work on both devices in any region, including Israel as long as the service provider offers it. The only thing I would recommend is you do some research on Exynos vs Snapdragon SoC's in the S10. Good luck!
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I am aware of the differences between the two chips.
In regards to WiFi Calling - I am a bit skeptical. This provider does have WiFi calling services, however they have a list of devices that are supported. Clearly they list devices and firmwares that they sell, not BYOD phones, and they sell the F version. I currently use ZTE Axon 7, I have WiFi calling on T-Mobile but it does not work on the Israeli network and when I try to 'register' it for this service through their app, it clearly says that the device is not supported.
That being said - I can't tell you if my phone doesn't work on their WF calling because it's not even sold in Israel. It could very well be that any version of Galaxy S10+ will be supported regardless of firmware. simply because it is sold there. Clearly there is no way to know this beforehand. I asked them, they of course can only guarantee phones that are sold by them and are on the list.
BTW - the Israeli version of the 975F is single SIM, they don't have the D/S, although I can't imagine this should have any impact of phone supporting or not supporting WF calling.
What's the difference between the F and the O, other than the region they are sold in?
Thanks.

Limeybastard said:
P20 pro was certified and worked fully on T-Mobile , most devices after that were not.
I don't think my mate 20x connected to band 12, but if it did, then yes it'll probably go straight to voicemail.
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Devices don't need to be certified by T-Mobile to work with Volte. All of my recent Xiaomi phones worked with Volte--none of the models were officially sold in the US or certified by T-Mobile. The P20 Pro was not sold in the US so there was zero reason for it to be certified by T-Mobile. The last Huawei phone officially sold here was the Mate 10 Pro. AT&T and Verizon require that devices be certified by them to work with Volte on their networks but T-Mobile does not. T-Mobile is very BYOP friendly.

jhs39 said:
Devices don't need to be certified by T-Mobile to work with Volte. All of my recent Xiaomi phones worked with Volte--none of the models were officially sold in the US or certified by T-Mobile. The P20 Pro was not sold in the US so there was zero reason for it to be certified by T-Mobile. The last Huawei phone officially sold here was the Mate 10 Pro. AT&T and Verizon require that devices be certified by them to work with Volte on their networks but T-Mobile does not. T-Mobile is very BYOP friendly.
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Thanks for the clarification. So why is it then that same device , but using different sim card would show the Volte toggle or hide it from the user menu? Example, mate 20 does have Volte capabilities yet its missing the Volte toggle switch. I know on the Xioami devices one can enter a #*code to force it show that option. I think what makes it even more convulsing is that Huawei global versions have various region firmware via their Cust codes. Each one I noticed behaves slighly different using same T-Mobile SIM card. Cheers
You mentioned all calls went to VM on up 20pro, why do you think that was the case, you mentioned earlier that you thought possibly it may have been firmware related amongst other things.
Sent from my SM-G975U using Tapatalk

sbi1 said:
I am aware of the differences between the two chips.
In regards to WiFi Calling - I am a bit skeptical. This provider does have WiFi calling services, however they have a list of devices that are supported. Clearly they list devices and firmwares that they sell, not BYOD phones, and they sell the F version. I currently use ZTE Axon 7, I have WiFi calling on T-Mobile but it does not work on the Israeli network and when I try to 'register' it for this service through their app, it clearly says that the device is not supported.
That being said - I can't tell you if my phone doesn't work on their WF calling because it's not even sold in Israel. It could very well be that any version of Galaxy S10+ will be supported regardless of firmware. simply because it is sold there. Clearly there is no way to know this beforehand. I asked them, they of course can only guarantee phones that are sold by them and are on the list.
BTW - the Israeli version of the 975F is single SIM, they don't have the D/S, although I can't imagine this should have any impact of phone supporting or not supporting WF calling.
What's the difference between the F and the O, other than the region they are sold in?
Thanks.
Click to expand...
Click to collapse
You're correct regarding Single SIM for the SM-G975F, the Dual SIM option is available in the SM-G975F/DS. I personally wouldn't consider obtaining a device in Israel if the majority of the time I'm the US. The major differences are SoC's, a minor difference in CPU Clock Speed and Cores. The SM-G975F has no FM Radio and offers fewer Primary Network capabilities. You can view a back-to-back comparison here.
https://www.phonemore.com/compare/p...gb-vs-galaxy-s10-plus-sm-g9750-128gb/10134260
This is quite different than your original question but with that being stated I would be confident enough in the SM-G9750's compatibility with the Israeli network for Wifi Calling. The worst case is not having Wifi Calling in Israel, which isn't an absolute necessity however you'll have the Snapdragon SoC which is a far better chipset with fewer bugs. For me it's the obvious choice if I were faced with your considerations.
You're most welcome

varcor said:
You're correct regarding Single SIM for the SM-G975F, the Dual SIM option is available in the SM-G975F/DS. I personally wouldn't consider obtaining a device in Israel if the majority of the time I'm the US. The major differences are SoC's, a minor difference in CPU Clock Speed and Cores. The SM-G975F has no FM Radio and offers fewer Primary Network capabilities. You can view a back-to-back comparison here.
https://www.phonemore.com/compare/p...gb-vs-galaxy-s10-plus-sm-g9750-128gb/10134260
This is quite different than your original question but with that being stated I would be confident enough in the SM-G9750's compatibility with the Israeli network for Wifi Calling. The worst case is not having Wifi Calling in Israel, which isn't an absolute necessity however you'll have the Snapdragon SoC which is a far better chipset with fewer bugs. For me it's the obvious choice if I were faced with your considerations.
You're most welcome
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Click to collapse
SoC, meaning the chip?
You see, your definition of "worst case not having Wifi calling" is important to me , simply because where I usually stay in Israel there is almost no reception at all (inside the house I am staying in), that's the main reason I want a device that will be able to use their Wifi calling.
Also, I looked at the eBay seller that you mention and I don't even think he carries the O model any more, all I see is the F model, unless of course I am missing something.
Thanks.

sbi1 said:
SoC, meaning the chip?
You see, your definition of "worst case not having Wifi calling" is important to me , simply because where I usually stay in Israel there is almost no reception at all (inside the house I am staying in), that's the main reason I want a device that will be able to use their Wifi calling.
Also, I looked at the eBay seller that you mention and I don't even think he carries the O model any more, all I see is the F model, unless of course I am missing something.
Thanks.
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Click to collapse
SoC is System on Chip, same as Chipset. If Wifi calling is a top priority buy the Exynos device to be certain but be advised there are numerous concerns over the chipset on XDA and other sites, plus Network Aggrigaton for Exynos in the US has issues with some T-Mobile clients. You may lose Wifi Calling or VoLTE in the US.
https://forum.xda-developers.com/s10-plus/help/exynos-att-t-mobile-t3920491
They still offer the SM-G9750, the link I shared is correct, not sure you missed something. The also sell the SM-G975F and SM-G975F/DS.