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Web Surfing while Talking

I know this is an odd request, but is there anyway to use the internet while talking on the phone. Normally I wouldn't care but I'm tired of the iPhone goons hassling me about it since those new commercials.
If not would there be a way if I unlocked my phone for GSM so I could talk on one frequency and surf on another?
Please direct me to a link if this has already been answered, I searched and didn't find anything.

Whoo boy, the old GSM vs. CDMA debate. No to your first question; it's a technology limitation of CDMA, which is why AT&T loves flaunting that fact. GSM also has the leg up in the number of simultaneous connections for conference calling. If you're looking for ammunition, CDMA generally enjoys better penetration of structures, and I know that I have found my service on Sprint to be stronger and much more reliable than my old plan with AT&T. Some people would even say that CDMA offers better call quality than GSM, but that's a huge debate with opinions on both sides. Also, GSM's encryption method was cracked recently, making calls potentially more vulnerable to eavesdropping. Finally, even when I had my old Tilt on AT&T I don't think I did too much surfing while talking on the phone; I really don't think it's as amazing a feature as they make it out to be.
For your second question, the CDMA Worldphone edition Touch Pro 2 used by Verizon and Sprint does have a GSM radio, but the question has been asked before if both networks can be used simultaneously and I believe the answer is always no. Anyone else feel free to correct me if I'm wrong.

last I checked in order to use cdma/gsm phone networks at the same time can't you just pop in a sim card!!!!!
trogdor1138 said:
Whoo boy, the old GSM vs. CDMA debate. No to your first question; it's a technology limitation of CDMA, which is why AT&T loves flaunting that fact. GSM also has the leg up in the number of simultaneous connections for conference calling. If you're looking for ammunition, CDMA generally enjoys better penetration of structures, and I know that I have found my service on Sprint to be stronger and much more reliable than my old plan with AT&T. Some people would even say that CDMA offers better call quality than GSM, but that's a huge debate with opinions on both sides. Also, GSM's encryption method was cracked recently, making calls potentially more vulnerable to eavesdropping. Finally, even when I had my old Tilt on AT&T I don't think I did too much surfing while talking on the phone; I really don't think it's as amazing a feature as they make it out to be.
For your second question, the CDMA Worldphone edition Touch Pro 2 used by Verizon and Sprint does have a GSM radio, but the question has been asked before if both networks can be used simultaneously and I believe the answer is always no. Anyone else feel free to correct me if I'm wrong.
Click to expand...
Click to collapse

one word IMPOSSIBLE!!!!!!!!!! GSM and CDMA are hardware radios an unlock is IMPOSSIBLE unless the phone is a world phone with both CDMA and GSM but your phone doesn't qualify so try getting a GSM/CDMA hybrid and then come back to me. However verizon will upgrade to LTE which is GSM based!!!!!!!! watch em LTE will allow voice and data at the same time. When LTE upgrade is complete say goodbye and good riddance to CDMA it will be shut down soon!!!!!
KW TP said:
I know this is an odd request, but is there anyway to use the internet while talking on the phone. Normally I wouldn't care but I'm tired of the iPhone goons hassling me about it since those new commercials.
If not would there be a way if I unlocked my phone for GSM so I could talk on one frequency and surf on another?
Please direct me to a link if this has already been answered, I searched and didn't find anything.
Click to expand...
Click to collapse

qjsmartphone - I thought that the TP2 was a world phone and thus held both antennas for cdma and gsm?
trogdor1138 -thanks for the input.
now I'm with sprint, and they offer 4G. This may be an ignorant comment, but can't a world phone with both antenna's say call on cdma and use the 4G provided by sprint? Or am I missing something? I kind of new at this so forgive the question if it is stupid. If there is a wiki on it please give me the link and I will be glad to read up. Thanks

qjsmartphone said:
one word IMPOSSIBLE!!!!!!!!!! GSM and CDMA are hardware radios an unlock is IMPOSSIBLE unless the phone is a world phone with both CDMA and GSM but your phone doesn't qualify so try getting a GSM/CDMA hybrid and then come back to me. However verizon will upgrade to LTE which is GSM based!!!!!!!! watch em LTE will allow voice and data at the same time. When LTE upgrade is complete say goodbye and good riddance to CDMA it will be shut down soon!!!!!
Click to expand...
Click to collapse
I'm not sure what you are talking about, but CDMA variant of Touch Pro 2 does have both GSM and CDMA hardware in them.
Also, LTE and WiMAX is a two new 4G technologies that will eventually replace 3G data.
LTE is not based on GSM, they are two different communication technologies.
Back to OP's question, if you are using CDMA branded TP2 you cannot surf and talk at a same time. It is limitation on CDMA technology.
4G and 3G is not compatible, is your grandparent's old 2G phone do 3G? no.
How about your 3G phone accesing 2G? yes. Usually when newer technology is being deployed, they make sure that it is backward compatible, so that they can lower battery consumption and remain accessible to area where new technology is not yet available.

Just be near wifi and then show them you can surf while talking.

segadc said:
Just be near wifi and then show them you can surf while talking.
Click to expand...
Click to collapse
I like the way you think

Or pop in a ATT or T-mobile SIM card and switch to GSM mode. The phone IS capable of voice and data when using GSM.

isdnmatt said:
Or pop in a ATT or T-mobile SIM card and switch to GSM mode. The phone IS capable of voice and data when using GSM.
Click to expand...
Click to collapse
I'll jump in here...
I thought Sprint/Verizon phones with both GSM/CDMA radios cannot use AT&T nor T-Mo SIM cards. I thought they only accepted the GSM SIM cards of countries outside the US.
Wait... HardSPL fixes that, doesn't it?... Oh well, I think I should stop stalking the CDMA forums when I have almost no idea on anything CDMA-related!
But, I'm still in favor of the WiFi suggestion!

mac people live in their own little world. don't let them bother you. sure, they can talk and surf the web at the same time...if they have 3g coverage. but there are areas where they have no coverage at all let alone 3g. then they can use the 'paper weight mode'. i also love how they tout their app store meanwhile we've had multiple wm app stores for years already. also i get to choose what apps i want to use without htc or sprint telling me what i'm allowed to.

segadc said:
Just be near wifi and then show them you can surf while talking.
Click to expand...
Click to collapse
this is what i would do
sumflipnol said:
I'll jump in here...
I thought Sprint/Verizon phones with both GSM/CDMA radios cannot use AT&T nor T-Mo SIM cards. I thought they only accepted the GSM SIM cards of countries outside the US.
Wait... HardSPL fixes that, doesn't it?... Oh well, I think I should stop stalking the CDMA forums when I have almost no idea on anything CDMA-related!
But, I'm still in favor of the WiFi suggestion!
Click to expand...
Click to collapse
i think you can use any SIM card you want if you phone is SIM Unlocked

yes you can use any sim card if your phone is sim unlock buy the Sprint TP2 is not working with us 3G

unlock
I called up VZW and told them I was going to Europe and wanted to use prepaid SIM cards instead of paying Big Red the $$. They gave me the SIM unlock code and now I can use T-Mo or AT&T SIM cards with no problem. Only downside is that their GSM frequencies are slightly off from the rest of the world so no high-speed data when using VZW on GSM carrier in the states...
Nate

qjsmartphone said:
one word IMPOSSIBLE!!!!!!!!!! GSM and CDMA are hardware radios an unlock is IMPOSSIBLE unless the phone is a world phone with both CDMA and GSM but your phone doesn't qualify so try getting a GSM/CDMA hybrid and then come back to me.
Click to expand...
Click to collapse
The CDMA Touch Pro 2 *is* a dual mode world phone with both GSM and CDMA.
sumflipnol said:
I'll jump in here...
I thought Sprint/Verizon phones with both GSM/CDMA radios cannot use AT&T nor T-Mo SIM cards. I thought they only accepted the GSM SIM cards of countries outside the US.
Click to expand...
Click to collapse
The Verizon TP2 has a simple SIM lock on it which is similar to standard GSM SIM locks. Remove the SIM lock and you can use any SIM card with a compatible network, including US networks.
The Sprint TP2 doesn't have a standard SIM lock, but instead has the US frequency bands disabled. Hence the need for a new radio.

At&t and T-Mobile HSPA+ can run same device?

I know how At&t are gonna have HSPA+ 4g, I'm confused about the new devices they're gonna have that support HSPA+. Are they going to be able to connect to HSPA+ on T-Mobile's network.
So for example, I buy an unlocked HSPA+ tablet from AT&T, straight from their store. Is it going to be able to use T-Mobile's HSPA+ network if I put a T-Mobile SIM card inside?
Also, one last question, if I use T-Mobile's SIM card, do I have to do some special stuff to get it to work on their cell network? Like how you have to unlock an iPhone for it to work on T-Mobile?
Thanks

xAliceNine said:
I know how At&t are gonna have HSPA+ 4g, I'm confused about the new devices they're gonna have that support HSPA+. Are they going to be able to connect to HSPA+ on T-Mobile's network.
So for example, I buy an unlocked HSPA+ tablet from AT&T, straight from their store. Is it going to be able to use T-Mobile's HSPA+ network if I put a T-Mobile SIM card inside?
Also, one last question, if I use T-Mobile's SIM card, do I have to do some special stuff to get it to work on their cell network? Like how you have to unlock an iPhone for it to work on T-Mobile?
Thanks
Click to expand...
Click to collapse
Hello,
Unfortunately you will not be able to use HSPA+. HSPA+ is just an extension/revision of the current 3G. Effectively it is also called 3.5G/3.75G in some reports. They use the same 3G band of each respective company. The At&t tablet would work on 850/1900 band and T-mobile will work on their AWS (1700) band. So if you bought an At&t tablet, you may need to get it unlocked, not sure if they lock the sim on tablets. At best you would get Edge service with a T-mobile sim.

thanks man, argg
do you think it's worth it to change to at&t because I just heard of the Motorola Atrix and it sound PRETTY BAD ASS!
I don't know since people I know are always angry at AT&T for their service either..

xAliceNine said:
thanks man, argg
do you think it's worth it to change to at&t because I just heard of the Motorola Atrix and it sound PRETTY BAD ASS!
I don't know since people I know are always angry at AT&T for their service either..
Click to expand...
Click to collapse
NP. I have had every major carrier offered in the US. I have had at&t, t-mobile, and sprint within the last year. I had verizon a while ago and dropped them because they could never get my bill right. Honestly, the service is about the same. The question is how is the service in your area. I mainly stay in my area about 90-98% of the time. I live in a major city so all carries have great service. But I have stayed with At&t for the last few years. Every time I go to another carrier I kept my at&t service, go figure. So I would just look at coverage to where you travel the most and go with a carrier that will give you the best coverage for the best price. Do i prefer a carrier over another, yeah. I like GSM carriers better because I do like to surf and talk at the same time. Sprint can do this if your in a 4G coverage area and have a 4G phone. Verizon is a no go with this feature until they release their LTE phones. But At&t has a better coverage footprint than T-mobile that is why I stick with them. Hope it helps.

Wondering a bit about this too.
I have service through Bendbroadband using a HSPA+ SIM with USB modem Dongle by bandluxe. The service is stellar on the speed, but I can't use the dongle with everything (iPad), so looking for alternate routes before i decide to move to a different provider.
I noticed that the CTO of the company said in a comment regarding their service that any unlocked UE that supports HSPA/HSPA+ in the AWS band could be used, but also had an unclear reponse on cell phones with HSPA+.
I have a Huawei Comet (unlocked), it lists the same AWS Bands compatible, but says HSDPA (which I thought HSDPA + HSUPA = HSPA+ but at higher speeds, correct me if I am wrong), and has hotspot tether that works with tmobile web service no problem.
I plugged the SIM in, and it updates the bar with BendBroadband but I get no data. (might need to provide the IMEI or something)..
Curious if you think it should work, before i go knocking on their doors.
Some other specs:
the mytouch 4g (HSPA+) lists the bands as:850 MHz;900 MHz;1800 MHz;1900 MHz;UMTS: Band IV (1700/2100)
The comet is listed as: 850 MHz;900 MHz;1800 MHz;1900 MHz;UMTS: Band I (2100);UMTS: Band IV (1700/2100)
I am fairly sure the comet is HSPA+ but not advertised that way.

According to comments on the site, Bendbroadband technicians do not actually support moving of the SIMs. Bummer.. trying to keep my business local.. Bumping and moving to Tmobile once the month is up.

[Q] Us Cellular phone cdma with sim slot (gsm option)

Ok, so I've searched all over and haven't had much luck. I have no experience with cdma phones, as t mobile is all I've ever had.
I was given a new US Cellular HTC Hero s. I opened it up and saw the sim slot and though, sweet I can replace my sensation with it (I smashed the screen pretty bad). Well, that was a no go, as the phone is cdma. Looking online though, I see it can run in gsm (options global mode, cdma mode, gsm / umts mode. I unlocked the bootloader using the htc site (not sure it matters) and popped in my sim card again, and tried both global and gsm mode, though neither got signal or would dial out. (under networks, it had the tmo apn info.)
So, is the GSM mode offered on this phone only for non US bands? Would a custom rom (now or down the road) allow it to work on tmo? I read something about the HTC Merge and someone being able to switch out the modem in the rom that allowed it to work in the US, but that is well beyond me. I can follow instructions, work ADB and flash roms.. but thats about it.
Is it possible, or will it soon be, to have this phone work on GSM or am I just stuck trying to sell it as a us cellular phone (or perhaps another cdma carrier.. like I said, I don't know anything about cdma)

As a Canadian I'm not sure about who owns US cellular or if they are their own company but I'm guessing they work like Verizon world phones. They have sim card slots but will work only outside of the US. If those verizon phones are used within the States, they will only pick up Verizon's frequency, as opposed to T-Mobile or AT&T where you can unlock them and use them with any GSM carrier within the States. But yeah, you can unlock it and it will work with any GSM carrier outside the States but within the States I think it will only work under US Cellular CDMA network...please correct me if I'm wrong.

That's right, u.s. cdma "world phones" have gsm radios but are locked down from connecting to gsm networks in the u.s. This is not just the normal sim lock found on gsm phones but they are hard coded to ignore u.s. gsm networks.
Some have been unlocked to work on any network through various methods including flashing a modem from a non-us varient of the same phone and other hacks. I can't comment specifically on this phone however.
Sent from my SPH-D700 using XDA App

Well, that points me in the right direction, and confirms what I read about swapping modems (on the other phone mentioned).
So basically it's software telling it not use a certain frequency, and not that the phone itself is incapable of picking it up (had my doubts about that)
Pretty shady the way phone companies are allowed to operate (don't get me started on my unlimited internet in my contract [pre data caps in tmo]. "Hey! check it out, this phone uses data 5 times faster than your old one, oh, and you get half as much too) sorry, end of rant.
I'll keep searching, and post if I find something..
On a side note, can cdma phones be flashed to another cdma carrier like verizon or sprint, or is it the same deal, coded to only use a certain frequency range?

only thing I've heard of is flashing sprint and verizon phones to cricket, metro pcs and boost.

How to make a GSM Radio for Thunderbolt

Hello
It sucks being an european and to have a 4g/cdma phone because in my country (Romania) you dont have a cdma network
So as we all know the Thunderbolt has the same chipset as the Rezound so in theory it should be able to transform into a Global Phone.
My question is why didn't anyone do that and how i can make one myself if a dev dosent bother.
I feel it in my guts that this will work but i need some guidelines, or someone with actual knowledge to help me.

charris said:
Hello
It sucks being an european and to have a 4g/cdma phone because in my country (Romania) you dont have a cdma network
So as we all know the Thunderbolt has the same chipset as the Rezound so in theory it should be able to transform into a Global Phone.
My question is why didn't anyone do that and how i can make one myself if a dev dosent bother.
I feel it in my guts that this will work but i need some guidelines, or someone with actual knowledge to help me.
Click to expand...
Click to collapse
Thunderbolt doesn't have the hardware. Not possible.

and what hardware are you talking about?

Thunderbolt has a CDMA radio and an LTE radio. Global phones need a separate GSM radio to work in Europe. If it has an unlocked SIM, the Thunderbolt should work on any 700mhz band LTE network, but is incompatible with GSM on all levels.
Sent from my ADR6400L using Tapatalk

MDM 9600
Actually, the Thunderbolt has an MDM 9600 baseband chipset that supports Hspa and Hspa+ which is a technology that At&t and T-mobile uses for their data connections. So, I believe that if the LTE radio is backwards compatible with those frequencies of At&t or T-mobile that it might work. The thunderbolt has two antennas: one for strictly CDMA and the other for lte and backwards compatibility to gsm/hspa(+) from what I understand. From what I have read Verizon has just opted to not install the drivers to support the GSM/HSPA(+) side of things. That, and the MSM 8650 processor or other hardware in the Thunderbolt may not support it. Just because the modem supports GSM/HSPA(+) doesn't mean the phone will, but I do think that if someone really wanted to they could modify the thunderbolt to work on GSM. The may need more hardware, but I do not know.
I would post the link about the chipset I have, but sadly as a noob it will not let me.
P.S. Verizon allows you to log-in to your account and view the unlock code for the thunderbolts SIM yourself. You do not have to call them. I have not used another Carriers SIM in my Thunderbolt, but HAVE read about people who have in other threads. Verizon from what I understand and have read on other forums does not allow you to use USA SIM cards other than VERIZON'S own SIM. From what I have read, it only unlocks the phone to use foreign country SIMs only. From what I had read, once you use VERIZON'S SIM unlock procedures a NEW menu pops up in your network settings giving you the option to select to use GSM only. The same thread was speaking about the iphone 4s and the Thunderbolt and said that Verizon allows for both to be unlocked and used as World Phones. I will not know for sure until I see proof, but I do know that Verizon allows you to unlock the Thunderbolt's SIM to use on Foreign Networks.

The MDM9600 baseband definitely supports quad-band GSM. However, the RF transceiver in the Thunderbolt may or may not, and the power amplifiers definitely do not. You need all three in order for a mode & band to actually work on a device.

Not possible from a hardware point of view.

Question Usa carrier support

I've asked this question before and I can't find anything.
Can anybody confirm the 0/B/E versions to work on TMobile or att or mvnos of them?
If someone wants to be so kindid appreciate it. Really wanting to buy one for root.

if you use AT&T, don't buy any international models because they will block your sim. You may call them to unlock it but the sim will be blocked again after a couple days. The reason is AT&T has a list of supported models and international phones are not on their list.
T-Mobile doesn't have such a horrible thing. So yeah, it works.
Oh, and I am using 908E/DS on T-Mobile network.

bobimbap said:
if you use AT&T, don't buy any international models because they will block your sim. You may call them to unlock it but the sim will be blocked again after a couple days. The reason is AT&T has a list of supported models and international phones are not on their list.
T-Mobile doesn't have such a horrible thing. So yeah, it works.
Oh, and I am using 908E/DS on T-Mobile network.
Click to expand...
Click to collapse
So when I purchase my S22 Ultra. I can use it on T-Mobile no issues? I assume it can be unlocked rooted and install custom roms.

doubledragon5 said:
So when I purchase my S22 Ultra. I can use it on T-Mobile no issues? I assume it can be unlocked rooted and install custom roms.
Click to expand...
Click to collapse
That’s what I’ve done and been using till now. Bought the 908E on Amazon, unlocked the bootloader and rooted it. No custom rom for it yet other than tha Magisk rom by dr.ketan. I’ve always been an AT&T customer in so many years. They refused to work with me to make my phone work on their network so I switch to T-mobile.
I’m using the S22 Ultra 908E on T-mobile to write this right now. I don’t see any issue. If there is one, the phone is the issue.

bobimbap said:
That’s what I’ve done and been using till now. Bought the 908E on Amazon, unlocked the bootloader and rooted it. No custom rom for it yet other than tha Magisk rom by dr.ketan. I’ve always been an AT&T customer in so many years. They refused to work with me to make my phone work on their network so I switch to T-mobile.
I’m using the S22 Ultra 908E on T-mobile to write this right now. I don’t see any issue. If there is one, the phone is the issue.
Click to expand...
Click to collapse
Carrier aggregation and 5g all working well for you on t-mobile?

The missing of band 71 if using on TMO, is a big loss. I wouldn't bother.

dj24 said:
Carrier aggregation and 5g all working well for you on t-mobile?
Click to expand...
Click to collapse
No. I don't expect an international phone to be fully working on a US carrier network such as TMO or ATT due to missing bands. If I have to choose between slower connection and the ability to root, I'd choose the latter one. I chose TMO because it works, white ATT not working at all.
There are wifi networks available almost everywhere I go nowadays. In case there is none, usually when I was driving, 4G/LTE always available and that's good enough.

bobimbap said:
No. I don't expect an international phone to be fully working on a US carrier network such as TMO or ATT due to missing bands. If I have to choose between slower connection and the ability to root, I'd choose the latter one. I chose TMO because it works, white ATT not working at all.
There are wifi networks available almost everywhere I go nowadays. In case there is none, usually when I was driving, 4G/LTE always available and that's good enough.
Click to expand...
Click to collapse
So to confirm, no signal at all for att/cricket?
What about h20wireless? Redpocket mobile?
What site to use to check compatibility? I'll take slower speeds

To confirm:
1. AT&T blocks your sim right away. Your phone turns into a small tablet. That's it. Nothing you can do about it. I don't bother with smaller companies. I only go for the big boys.
2. T-Mobile will give you slower speed and freedom of root. This comes from my experience. Very little chance I need to use my plan's data. I can't tell the speed is slower at all. As far as carrier's features, I don't use any of them, but I think you can still have them if you change it to proper CSC.
Google search your model then you will find what bands your model support. Then Google search your choice of carrier to see what bands they have. Google is your friend.

Not just slower speed. Theres some areas that band 71 would be required to even get service at all in rural areas. Like just 5 min from my house if you have T-Mobile and your phone doesnt have band 71 no service.

hyelton said:
Not just slower speed. Theres some areas that band 71 would be required to even get service at all in rural areas. Like just 5 min from my house if you have T-Mobile and your phone doesnt have band 71 no service.
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Click to collapse
Will Samsung Galaxy S22 Ultra work in USA?
In this page we are going to show you the compatibility of Samsung Galaxy S22 Ultra with the mobile networks of USA and with the telephony operators that provide service in USA.
www.kimovil.com
This site is what I used and it looks like the version I want to get will suffice. But what do you think?

this.guy.lol said:
Will Samsung Galaxy S22 Ultra work in USA?
In this page we are going to show you the compatibility of Samsung Galaxy S22 Ultra with the mobile networks of USA and with the telephony operators that provide service in USA.
www.kimovil.com
This site is what I used and it looks like the version I want to get will suffice. But what do you think?
Click to expand...
Click to collapse
All depends on area. It's still missing band 71 and N71 5G. I personally couldn't as it would make my phone useless in areas I frequent

hyelton said:
All depends on area. It's still missing band 71 and N71 5G. I personally couldn't as it would make my phone useless in areas I frequent
Click to expand...
Click to collapse
But you could get the 4G LTE tho at least right? I have a 5G phone and i only get LTE speeds which is fine but the carrier doesn't offer 5G.

this.guy.lol said:
But you could get the 4G LTE tho at least right? I have a 5G phone and i only get LTE speeds which is fine but the carrier doesn't offer 5G.
Click to expand...
Click to collapse
No. Band 71 is an LTE band on TMobile.

hyelton said:
No. Band 71 is an LTE band on TMobile.
Click to expand...
Click to collapse
Ohh ok.

hyelton said:
Not just slower speed. Theres some areas that band 71 would be required to even get service at all in rural areas. Like just 5 min from my house if you have T-Mobile and your phone doesnt have band 71 no service.
Click to expand...
Click to collapse
In the end, as @hyelton just said, it all depends on your area, your luck and how you would use your phone... There is no definite answer to the op's question until he figures it out himself. It works for me and I am happy with what I got but that may not apply to everyone else... If the op decides to roll the dice for a chance to get a phone that he can have total freedom over it he can go for it. Otherwise, just buy the one on Samsung website ending with U models and have all of his worries put away. Honestly, I didn't think about any of that when I placed my order.

My unlocked 908U1 on t-mobile work perfectly, supported band25 with 130-180mbps speeds on LTE.
ps: 5G is totally disabled as it switching every 5 seconds between 4G\5G networks

malikin said:
My unlocked 908U1 on t-mobile work perfectly, supported band25 with 130-180mbps speeds on LTE.
ps: 5G is totally disabled as it switching every 5 seconds between 4G\5G networks
Click to expand...
Click to collapse
My OP was based on the international versions because I absolutely have to have root. I have not owned a phone that I could not have root capabilities in over 10 years.
I don't care so much about 5G I just want to have a phone that functions on a US carrier from overseas. Maybe it got lost in translation but I just want to know what carriers people have and if anybody has the carriers that I mentioned with confirmation or denial of service.
Specifically the carriers on most questioned about are H2O wireless and red pocket. I'm not very Google friendly and so I'm not familiar with the bands I'm used to just buying a phone and it working as intended for my purposes.

^^^ You're overthinking it. Just pull up the bandwidths for the carrier you're looking to utilize and go from there. As mentioned you're better served by going for one of the major carriers and maybe their prepaid services. Remember major carriers prioritize their post paid plans first for their optimum network traffic followed by their own respective prepaid plans and finally the MVNOs. I would stay away from the MVNOs in your scenario if you're importing a handset not configured for the U.S to begin it and degrading it further by using an MVNO.