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Root Flashing radio firmware for domestic GSM carriers


Jul 21, 2014
I have a rooted and unlocked (for global usage only) Droid 3 (xt862) with Cyanogenmod 9 on Verizon that I would like to use on another carrier in the U.S. The unlock code Verizon gave me only unlocked the phone for use outside the U.S., and I understand that the radio firmware needs to be flashed in order to unlock the phone for domestic U.S. usage with other carriers.

I have read the instructions at "Guide - Unlock XT862 for T-mobile/ATT"on xda-developers, but I still have some questions.

1. Can I do this from linux? The android hacking world seems to be full of one-click do-it-for-you Windows apps like the "moto-fastboot.exe" one used for flashing radio firmware. Ironic, isn't it?

2. Do I need to have Fastboot installed? Do I already have Fastboot installed? What exactly is Fastboot, anyway? And how does it compare to SafeStrap?

3. Can this be done from SafeStrap? If possible, SS sounds like the easiest option.

4. Can I just extract the contents of the "radio.img" filesystem into the root of my CM9 installation? It sounds like an accident waiting to happen, but I should be able to recover from SS if anything goes wrong.

5. What is a "build.prop" file? Do these options take effect at compile-time or at run-time? Can I modify my existing /system/build.prop file and viola? I can post my existing one if necessary.

6. Will CDMA still work? Some people have reported that CDMA (Verizon) stops working when the xt883 after-market radio is flashed onto the Droid 3 to unlock domestic GSM.

Lots of questions, I know. Any help is appreciated, even if you can't answer them all. The main issue is that I don't have access to any Windows machines presently. The sooner I can ditch Verizon, the better.


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