[HOWTO] / [GUIDE] SPH-L720 Domestic SIM Unlock T-Mobile:AT&T:metroPCS:Straighttalk

ecs87

Senior Member
Nov 17, 2012
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Agreed with the above. Never mix and match. We USED to be able to benefit from newer modems on older firmware but now...A lot has changed. Damn you 4.3 and 4.4.2!

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deadly59

Member
Nov 29, 2006
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Agreed with the above. Never mix and match. We USED to be able to benefit from newer modems on older firmware but now...A lot has changed. Damn you 4.3 and 4.4.2!

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haha ya I am kinda mix and matching I couldn't figure out how to change the APN on TriForce 5.3 so I changed it to a t-mobile rom (wicked 10) but its based off of 4.3. the modem I am running MF9 baseband and wanted to update it to the latest version to get better reception. I can't figure out how to do it without bricking my sound. I think maybe if I flash it to a 4.4.2 ROM than try it I might have better luck... I'll wait till my days off :) attached is my set up

 

CyberpodS2

Senior Member
Mar 27, 2012
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If you're on MF9 everything, then EVERYTHING has to be MF9, including your modem.


Just an update for anyone who might be in the same boat. I had it working originally and then at some point it the voice call function got weird. (like when I changed modems prolly) All my data and wifi was fine but the voice call stuff was boned. As it turns out like quoted here, I switched back from NAE modem to MF9 (I have the MF9 firmware still) and all is good to go now. Thanks bro for helping us man!

Oh and for reference sake, I am running a TMO build of Carbon Rom built by ShadySide.
 
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ecs87

Senior Member
Nov 17, 2012
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Is there an international carrier free firmware for this phone?

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Even if there was, how would you get past the secure bootloader? This isn't the ICS days where you can flash any variant's build onto your phone (and possibly brick it...hence the need for a secured bootloader from Samsung/qualcomm).

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Dez Playamade

Member
Apr 14, 2014
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I see 4g enabled: false when I use the sprint diagnostics app maybe we need a toggle mod to turn it on and off like wifi

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iBowToAndroid

Senior Member
Nov 9, 2010
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www.droid-life.com
Is there an international carrier free firmware for this phone?

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I see 4g enabled: false when I use the sprint diagnostics app maybe we need a toggle mod to turn it on and off like wifi

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I **** u not...I believe the answer to this is in the build prop can someone investigate?

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No there's no international firmware. Some users are able to use T-Mo ROMs to some degree of success I think. But what is it that you're trying to accomplish, with the whole 4G status and comment about the build.prop?
 

ecs87

Senior Member
Nov 17, 2012
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I **** u not...I believe the answer to this is in the build prop can someone investigate?

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I'm 99.9999% sure the answer isn't in the build.prop. I think the answer was explained earlier and commented on the supported bands

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Dez Playamade

Member
Apr 14, 2014
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I read elsewhere that someone got the full 4g network on a nexus device after build prop edits but I cant get the ones under data to change

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---------- Post added at 01:27 AM ---------- Previous post was at 01:22 AM ----------

They were getting the same H+ data connection at first

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AndroidKing

Senior Member
May 6, 2010
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I read elsewhere that someone got the full 4g network on a nexus device after build prop edits but I cant get the ones under data to change

Sent from my SPH-L720 using xda app-developers app

---------- Post added at 01:27 AM ---------- Previous post was at 01:22 AM ----------

They were getting the same H+ data connection at first

Sent from my SPH-L720 using xda app-developers app
On the Nexus 4 it has Lte band 4 which tmo is supporting which sprint phone doesnt support lte bands tmo and at&t
 
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ecs87

Senior Member
Nov 17, 2012
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anyway to do this on mk2 ?
please desperately need to unlock my phone
It's been throughly explained how to perform this unlock on any build up to the current one (NAE). You're going to have to do some reading through the thread.

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Brainfeederz

Member
Dec 16, 2013
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It's been throughly explained how to perform this unlock on any build up to the current one (NAE). You're going to have to do some reading through the thread.

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Thanks i actualy got this to work with a t-mobile sim and i get data , text/mms & voice. i'm recieving H+ :)

But only one problem when i'm on the phone i can't hang up the call unless the other person hangs up 1st

I'll press hang up and nothing happens. I can still hear the other caller. I'm running Pac-rom for t-mobile.

any way around this or a solution ? please and thanks
 

ecs87

Senior Member
Nov 17, 2012
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Thanks i actualy got this to work with a t-mobile sim and i get data , text/mms & voice. i'm recieving H+ :)

But only one problem when i'm on the phone i can't hang up the call unless the other person hangs up 1st

I'll press hang up and nothing happens. I can still hear the other caller. I'm running Pac-rom for t-mobile.

any way around this or a solution ? please and thanks
Again, mentioned previously in the thread. I don't know why people perform baseband hacks and then expect a custom ROM to work. You guys are exponentially adding factors causing problems. Stick with the stock ROM from Sprint. After the unlock, Odin your current build firmware's MODEM ONLY! Meaning if you're on MF9 and downgraded the modem to MDC for the unlock, put the MF9 modem back on. If you were on MK2 after the unlock flash the MK2 modem. Everything will work fine. At this point leave everything (firmware and connection settings) alone. I've done this for about 50 people and not one has come back with an issue.

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Brainfeederz

Member
Dec 16, 2013
20
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0
Again, mentioned previously in the thread. I don't know why people perform baseband hacks and then expect a custom ROM to work. You guys are exponentially adding factors causing problems. Stick with the stock ROM from Sprint. After the unlock, Odin your current build firmware's MODEM ONLY! Meaning if you're on MF9 and downgraded the modem to MDC for the unlock, put the MF9 modem back on. If you were on MK2 after the unlock flash the MK2 modem. Everything will work fine. At this point leave everything (firmware and connection settings) alone. I've done this for about 50 people and not one has come back with an issue.

Sent from my SPH-L720 using xda app-developers app

Okay i understand. So i won't be able to use any custom roms at all after i unlock and after i flash back to the mk2 modem? i like CM11 & custom themes :(

will i be able to at least root my phone or update to 4.4.2 without losing unlock ?

please reply asap
 
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