Unlocking bands for NA usage

[Magendanz]

As has been documented on many XDA forums, we can make modifications to NVRAM on Qualcomm devices to unlock RF and LTE bands that have been disabled by the OEM. I decided to take a crack at this on the Mi A2 Lite with some mixed results, and am looking for suggestions. First of all, here are the "secret" phone codes that you'll need:

Enable Diagnostics Mode: *#*#717717#*#*
Info Menu: *#*#4636#*#*

From this last, there's a Phone Info section that allows you to set the Preferred Network Type. By default, this is LTE/UTS auto (PRL), where PRL stands for Preferred Roaming List. In the page menu, there's also Select Radio Band, which allows you to select either Automatic or United States.

For details on how to make changes to NVRAM on Qualcomm phones, I'll direct you to this thread for the Xiaomi Mi Note Pro. Here are the relevant values:

ID    Desc             Category   Original Value       Modified Value
01877 rf_bc_config     CDMA       562950035735424      562950069289856
06828 lte_bc_config    LTE        687195291871         1787696847071
65633 lte_band_pref    System     0x000000A0000800DF   0x0000FFFFFFFFFFFF

ID    Desc             Category   Original Value   U.S.     Automatic   Cleared
00441 band_pref        CDMA       0x0380           0x0000   0xFFFF      0xFFFF
00946 band_pref_16_31  System     0x04E8           0x04A8   0xBFFF      0x3FFF
02954 band_pref_32_63  System     131072           0        252116992   4294967295

For a better understanding of these values, I recommend this thread which includes RF band descriptions. Note that the band prefs (a.k.a. "forcings") can be cleared with Network Signal Guru (Cleared) or set with the Select Radio Band command (U.S. or Automatic).

Let's tackle the RF bands first. I used my Nexus 5X as a reference, since it was advertised by Google as having "universal" band support.

rf_bc_config (64-bit):
562950035735424          00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
562950069306247          00000000 00000010 00000000 00000000 00000110 11101000 01000011 10000111 (Nexus 5X)
562950069289856          00000000 00000010 00000000 00000000 00000110 11101000 00000011 10000000 (Modified)

band_pref (64-bit):
   131072 0x04E8 0x0380  00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
        0 0x04A8 0x0000  00000000 00000000 00000000 00000000 00000100 10101000 00000000 00000000 (U.S. Mode)
252116992 0xBFFF 0xFFFF  00001111 00000111 00000000 00000000 10111111 11111111 11111111 11111111 (Automatic)

So, we're just looking at unlocking the following RF band for T-Mobile support:

#25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz)

On LTE we're getting a bit more aggressive:

lte_bc_config (64-bit, of which 44 bits relevant):               Bands Active:
 687195291871 0000 10100000 00000000 00001000 00000000 11011111  1-5,7-8,20,38,40 (Original)
1099830990943 0001 00000000 00010011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,29,41 (Nexus 5x)
1100502079583 0001 00000000 00111011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,28-30,41 (Pixel)
1787698289887 0001 10100000 00111011 00011111 00011100 11011111  1-5,7-8,11-13,17-21,25-26,28-30,38,40-41 (Pixel 2)
1787696847071 0001 10100000 00111011 00001001 00011000 11011111	 1-5,7-8,12-13,17,20,25-26,28-30,38,40-41 (Modified)
1787696847071 0001 10100000 00001000 00001000 00000000 11011111	 1-5,7-8,20,28,38,40-41 (Actual)

My goal was to add LTE bands 12-13, 17, 25-26, 28-30 & 41, but as you can see I was only successfully able to add bands 28 & 41. In particular, LTE band 17 is critical to AT&T Wireless in the U.S.

Does anyone understand why some bands were unable to be unlocked, even after setting lte_band_pref to allow pretty much anything? Are there additional NVRAM settings that I missed, or is this due to lack of support in the power amplifier? Does anyone even know the model of power amplifier used in this phone?

 

[kamiyaa]

Hey, I tried following this. But I have a few questions.
1. you show the values of 00441, 00946, 02954 that are set when in automatic/US and original. Are there any changes to make to these? When I set to Automatic, I get 'mobile network unavailable' when making a call. When I set it to US, it switches between B2 and B5 when calling.
2. After setting 01877, 06828 and 65633 to the modified values, I am still unable to connect to #25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz).
Namely, when I open up Network Signal Guru and make a call, it switches between B2 and B5. Any idea why this is and how to get B4 1700 3g umts working?

Thanks

 

[Magendanz]

Hey, I tried following this. But I have a few questions.
1. you show the values of 00441, 00946, 02954 that are set when in automatic/US and original. Are there any changes to make to these? When I set to Automatic, I get 'mobile network unavailable' when making a call. When I set it to US, it switches between B2 and B5 when calling.

2. After setting 01877, 06828 and 65633 to the modified values, I am still unable to connect to #25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz).
Namely, when I open up Network Signal Guru and make a call, it switches between B2 and B5. Any idea why this is and how to get B4 1700 3g umts working?

Well, setting to Automatic shouldn't mask any bands enabled in rf_bc_config, at least not for any of the rf_bc_config settings that I examined. I don't have a T-Mobile SIM card, however, so I wasn't able to confirm that WCDMA Band IV was picked up when you set bit #25. If you set it to U.S. Mode, however, it will definitely get masked.

 

[Magendanz]

The one thing I would recommend, however, is to avoid using Preferred Roaming Lists (PRLs) in the Set Preferred Network Type setting.

For example, my instinct was to use LTE/UMTS auto (PRL), which should prefer 4G connections and fall back to 3G when unavailable. However, I've had consistently better luck getting 4G connections when I use the default LTE/TD-SCDMA/UMTS setting. On the AT&T Wireless network we'll never use TD-SCDMA, but PRLs seem to be causing problems and there's no plain LTE/UMTS option. The PRL indicates which bands, sub bands, and service provider identifiers will be scanned and in what priority order, and I just don't believe these are configured correctly on this phone for North America.

 

[Delu08]

Hello,
Sorry to bother you, but may I ask a few stupid questions?
I don't know much about how this works, but I've got a Mi A2 and I've seen you managed to unlock band 28 for LTE in the Lite version, and that is the only band I'm missing in my country. Is this that hard to do, and possible in the regular A2 version? I need to unlock bootloader and root for this, right? If it's not difficult, I would appreaciate some instructions if you don't mind
Thanks!

 

[Antho02]

Enable Diagnostics Mode: *#*#717717#*#*
Info Menu: *#*#4636#*#*
From this last, there's a Phone Info section that allows you to set the Preferred Network Type. By default, this is LTE/UTS auto (PRL), where PRL stands for Preferred Roaming List. In the page menu, there's also Select Radio Band, which allows you to select either Automatic or United States.

Well i have tried switching here to test different ones and now it looks i cant access internet anymore :'(
even if i have the 4G logo on my network, the traffic is like stopped, chrome or any app say i am not connected.
If anyone have any idea to get it back? Thanks in advance ( i use french 4G network, Bouygues Telecom)

 

[Magendanz]

If anyone have any idea to get it back?

Original values are posted above, which you can write back pretty easily with QXDM. Also, if you made a QPST backup (which I recommend), you can restore from that.

 

[boe323]

I tried this, but it killed vodafone UK LTE, also, what subscription do you use for dual sim?, thats got to mess things up if you dont tick it on dual sim phones??, because i didnt choose dual sim it only edited sim1, so if you know the subscription method could you please post.

 

[marcos1979]

Hi, I'm trying to unlock the band 28 but I can not install the drivers. Could you tell me which are the correct drivers? Thank you and sorry for my lousy English!

 

[boe323]

Hi, I'm trying to unlock the band 28 but I can not install the drivers. Could you tell me which are the correct drivers? Thank you and sorry for my lousy English!

enable the port and just update in devices, under ports, the driver in this thread isnt mi a2 lite diagnostic driver, windows installs the correct one if your using latest win 10

 

[marcos1979]

enable the port and just update in devices, under ports, the driver in this thread isnt mi a2 lite diagnostic driver, windows installs the correct one if your using latest win 10

Sorry to insist with these questions, it's my first time with Xiaomi. The steps I take are the following and I can not install the drivers (the devices do not appear in the Windows Device Manager) and I can not install QPST either:
* Enable USB debugging
* Activate USB Diag (*#*#717717#*#*)
* Connect the phone

Only "Android Composite ADB Interface" is observed in the Device Manager.
The installation of QPST is canceled before completion.

Is it necessary to enable root?
Is it necessary to unlock the bootloader?

Sorry, as I said it's my first time with Xiaomi, I come from Motorola. I need to enable band 28 to have better coverage here in Argentina because in my area it is very bad without that band.

Additional data:
Xiaomi Mi A2 Lite (M1805D1SG)
Build number: PKQ1.180917.001.V10.0.4.0.PDLMIXM
Windows 10 Pro x64 (1809)

Thanks and, again, sorry for my English (Google translator)

 

[marcos1979]

OK, I was able to make everything work !!!

I used "TOOL_ALL_IN_ONE_1.1.1.2" to install the ADB drivers and from there the other drivers were installed. Also, I used "QPST 2.7 Build 474" and "QXDM 0.3.12.714"

A new question: I need to only enable band 28 for LTE (the others are compatible with those used in my country), is it OK to only modify line 6828 (LTE_BC_CONFIG) to the value "687329509599"? Am I doing things right?
The tests I will do tomorrow in an area where there is bad coverage of band 4 and good band coverage 28.

Thank you!!!

 

[boe323]

im not sure, make a note of original values and do your own testing, post back with your findings.

 

[marcos1979]

im not sure, make a note of original values and do your own testing, post back with your findings.

Edited:
I confirm that the band 28 is not enabled since it does not connect in the area of ​​low coverage in band 4. I suspect that is because I could not modify the line 65633 (lte_band_pref) for the error nv status error received: command unrecognized.
please, I need help to modify that! Thank you!

thanks for your help.

the only thing I could not do is edit line 65633 lte_band_pref, it gives me read error (nv status error received: command unrecognized). what am I doing wrong?
Do I need to enable root? Do I need to unlock the bootloader?

Thanks!

 

[marcos1979]

As has been documented on many XDA forums, we can make modifications to NVRAM on Qualcomm devices to unlock RF and LTE bands that have been disabled by the OEM. I decided to take a crack at this on the Mi A2 Lite with some mixed results, and am looking for suggestions. First of all, here are the "secret" phone codes that you'll need:

Enable Diagnostics Mode: *#*#717717#*#*
Info Menu: *#*#4636#*#*

From this last, there's a Phone Info section that allows you to set the Preferred Network Type. By default, this is LTE/UTS auto (PRL), where PRL stands for Preferred Roaming List. In the page menu, there's also Select Radio Band, which allows you to select either Automatic or United States.

For details on how to make changes to NVRAM on Qualcomm phones, I'll direct you to this thread for the Xiaomi Mi Note Pro. Here are the relevant values:

ID    Desc             Category   Original Value       Modified Value
01877 rf_bc_config     CDMA       562950035735424      562950069289856
06828 lte_bc_config    LTE        687195291871         1787696847071
65633 lte_band_pref    System     0x000000A0000800DF   0x0000FFFFFFFFFFFF

ID    Desc             Category   Original Value   U.S.     Automatic   Cleared
00441 band_pref        CDMA       0x0380           0x0000   0xFFFF      0xFFFF
00946 band_pref_16_31  System     0x04E8           0x04A8   0xBFFF      0x3FFF
02954 band_pref_32_63  System     131072           0        252116992   4294967295

For a better understanding of these values, I recommend this thread which includes RF band descriptions. Note that the band prefs (a.k.a. "forcings") can be cleared with Network Signal Guru (Cleared) or set with the Select Radio Band command (U.S. or Automatic).

Let's tackle the RF bands first. I used my Nexus 5X as a reference, since it was advertised by Google as having "universal" band support.

rf_bc_config (64-bit):
562950035735424          00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
562950069306247          00000000 00000010 00000000 00000000 00000110 11101000 01000011 10000111 (Nexus 5X)
562950069289856          00000000 00000010 00000000 00000000 00000110 11101000 00000011 10000000 (Modified)

band_pref (64-bit):
   131072 0x04E8 0x0380  00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
        0 0x04A8 0x0000  00000000 00000000 00000000 00000000 00000100 10101000 00000000 00000000 (U.S. Mode)
252116992 0xBFFF 0xFFFF  00001111 00000111 00000000 00000000 10111111 11111111 11111111 11111111 (Automatic)

So, we're just looking at unlocking the following RF band for T-Mobile support:

#25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz)

On LTE we're getting a bit more aggressive:

lte_bc_config (64-bit, of which 44 bits relevant):               Bands Active:
 687195291871 0000 10100000 00000000 00001000 00000000 11011111  1-5,7-8,20,38,40 (Original)
1099830990943 0001 00000000 00010011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,29,41 (Nexus 5x)
1100502079583 0001 00000000 00111011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,28-30,41 (Pixel)
1787698289887 0001 10100000 00111011 00011111 00011100 11011111  1-5,7-8,11-13,17-21,25-26,28-30,38,40-41 (Pixel 2)
1787696847071 0001 10100000 00111011 00001001 00011000 11011111	 1-5,7-8,12-13,17,20,25-26,28-30,38,40-41 (Modified)
1787696847071 0001 10100000 00001000 00001000 00000000 11011111	 1-5,7-8,20,28,38,40-41 (Actual)

My goal was to add LTE bands 12-13, 17, 25-26, 28-30 & 41, but as you can see I was only successfully able to add bands 28 & 41. In particular, LTE band 17 is critical to AT&T Wireless in the U.S.

Does anyone understand why some bands were unable to be unlocked, even after setting lte_band_pref to allow pretty much anything? Are there additional NVRAM settings that I missed, or is this due to lack of support in the power amplifier? Does anyone even know the model of power amplifier used in this phone?

Hello, sorry for insisting. I was able to edit the item 06828 lte_bc_config and put it in 687329509599 (1010000000001000000010000000000011011111) (Bands 1-5, 7-8, 20, 28, 38, 40) but I still do not have coverage in band 28 although other phones do have in the Same location and with the same provider.
After enabling root and touching several things (Install Network Signal Guru -> Clear Forcings and I do not know if I have played anything else), I can read line 65633 lte_band_pref and it appears in 0x0000FFFFFFDF3FFF (111111111111111111111111110111110011111111111111) (Bands 1-14, 17-21 , 23-48) (?) So I assume that band 28 would be enabled. In Network Signal Guru I can see that band 28 is enabled but I still can not connect to it. Is there something I'm missing? Could it be a SIM problem? (I use a SIM that was cut to nanoSIM) Could someone unblock band 28 and connect to it?
Any help will be welcome!
Thank you!

PS: I was not sure whether to edit the previous post or create a new one. If I am doing wrong, please delete the previous one.

(Using Google Translator)

 

[Magendanz]

I'm having the same problem trying to get LTE Band 17 enabled for AT&T Wireless. I can read both lte_bc_config and lte_band_pref in QXDM to confirm that it *should* be enabled, but it's not picking up the nearby towers. That has me suspecting that this is due to lack of support in the power amplifier. When I look in Network Signal Guru it's not even listing Band 17, however, so there may be something else that we're missing.

I did just pick up another Mi A2 Lite, and so I've got test hardware (that isn't my primary phone) to investigate further.

 

[Samuelah]

As has been documented on many XDA forums, we can make modifications to NVRAM on Qualcomm devices to unlock RF and LTE bands that have been disabled by the OEM. I decided to take a crack at this on the Mi A2 Lite with some mixed results, and am looking for suggestions. First of all, here are the "secret" phone codes that you'll need:

Enable Diagnostics Mode: *#*#717717#*#*
Info Menu: *#*#4636#*#*

From this last, there's a Phone Info section that allows you to set the Preferred Network Type. By default, this is LTE/UTS auto (PRL), where PRL stands for Preferred Roaming List. In the page menu, there's also Select Radio Band, which allows you to select either Automatic or United States.

For details on how to make changes to NVRAM on Qualcomm phones, I'll direct you to this thread for the Xiaomi Mi Note Pro. Here are the relevant values:



For a better understanding of these values, I recommend this thread which includes RF band descriptions. Note that the band prefs (a.k.a. "forcings") can be cleared with Network Signal Guru (Cleared) or set with the Select Radio Band command (U.S. or Automatic).

Let's tackle the RF bands first. I used my Nexus 5X as a reference, since it was advertised by Google as having "universal" band support.



So, we're just looking at unlocking the following RF band for T-Mobile support:

#25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz)

On LTE we're getting a bit more aggressive:



My goal was to add LTE bands 12-13, 17, 25-26, 28-30 & 41, but as you can see I was only successfully able to add bands 28 & 41. In particular, LTE band 17 is critical to AT&T Wireless in the U.S.

Does anyone understand why some bands were unable to be unlocked, even after setting lte_band_pref to allow pretty much anything? Are there additional NVRAM settings that I missed, or is this due to lack of support in the power amplifier? Does anyone even know the model of power amplifier used in this phone?

How did you enable band 28 ? Can you recommend any article on that kindly

 

[Magendanz]

How did you enable band 28 ? Can you recommend any article on that kindly

I followed the steps in my OP exactly (and there are links there to my sources), but was unable to test band 28 & 41 because my service provider doesn't use them. I just know that they now show as enabled in Network Signal Guru.

 

[ada12]

B28 unlocked

Its worked for me I have tested 700 mhz ( B28 ) is unlocked

 

[ada12]

add carrier aggregation lte-a 4g+

If you want lte-a in mi a2 lite for frequency added (support 2*2 carrier aggregation only ( 2*frequency )) so Its Enable LTE Advanced I have found guide for mi a1 but its work for this devices too here :https://forum.xda-developers.com/mi-a1/how-to/guide-enable-4g-lte-carrier-aggregation-t3894282

good modding :good:

As has been documented on many XDA forums, we can make modifications to NVRAM on Qualcomm devices to unlock RF and LTE bands that have been disabled by the OEM. I decided to take a crack at this on the Mi A2 Lite with some mixed results, and am looking for suggestions. First of all, here are the "secret" phone codes that you'll need:

Enable Diagnostics Mode: *#*#717717#*#*
Info Menu: *#*#4636#*#*

From this last, there's a Phone Info section that allows you to set the Preferred Network Type. By default, this is LTE/UTS auto (PRL), where PRL stands for Preferred Roaming List. In the page menu, there's also Select Radio Band, which allows you to select either Automatic or United States.

For details on how to make changes to NVRAM on Qualcomm phones, I'll direct you to this thread for the Xiaomi Mi Note Pro. Here are the relevant values:

ID    Desc             Category   Original Value       Modified Value
01877 rf_bc_config     CDMA       562950035735424      562950069289856
06828 lte_bc_config    LTE        687195291871         1787696847071
65633 lte_band_pref    System     0x000000A0000800DF   0x0000FFFFFFFFFFFF

ID    Desc             Category   Original Value   U.S.     Automatic   Cleared
00441 band_pref        CDMA       0x0380           0x0000   0xFFFF      0xFFFF
00946 band_pref_16_31  System     0x04E8           0x04A8   0xBFFF      0x3FFF
02954 band_pref_32_63  System     131072           0        252116992   4294967295

For a better understanding of these values, I recommend this thread which includes RF band descriptions. Note that the band prefs (a.k.a. "forcings") can be cleared with Network Signal Guru (Cleared) or set with the Select Radio Band command (U.S. or Automatic).

Let's tackle the RF bands first. I used my Nexus 5X as a reference, since it was advertised by Google as having "universal" band support.

rf_bc_config (64-bit):
562950035735424          00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
562950069306247          00000000 00000010 00000000 00000000 00000110 11101000 01000011 10000111 (Nexus 5X)
562950069289856          00000000 00000010 00000000 00000000 00000110 11101000 00000011 10000000 (Modified)

band_pref (64-bit):
   131072 0x04E8 0x0380  00000000 00000010 00000000 00000000 00000100 11101000 00000011 10000000 (Original)
        0 0x04A8 0x0000  00000000 00000000 00000000 00000000 00000100 10101000 00000000 00000000 (U.S. Mode)
252116992 0xBFFF 0xFFFF  00001111 00000111 00000000 00000000 10111111 11111111 11111111 11111111 (Automatic)

So, we're just looking at unlocking the following RF band for T-Mobile support:

#25 WCDMA Band IV - US T-Mobile (AWS) (1700 MHz)

On LTE we're getting a bit more aggressive:

lte_bc_config (64-bit, of which 44 bits relevant):               Bands Active:
 687195291871 0000 10100000 00000000 00001000 00000000 11011111  1-5,7-8,20,38,40 (Original)
1099830990943 0001 00000000 00010011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,29,41 (Nexus 5x)
1100502079583 0001 00000000 00111011 00001001 00011000 01011111  1-5,7,12-13,17,20,25-26,28-30,41 (Pixel)
1787698289887 0001 10100000 00111011 00011111 00011100 11011111  1-5,7-8,11-13,17-21,25-26,28-30,38,40-41 (Pixel 2)
1787696847071 0001 10100000 00111011 00001001 00011000 11011111	 1-5,7-8,12-13,17,20,25-26,28-30,38,40-41 (Modified)
1787696847071 0001 10100000 00001000 00001000 00000000 11011111	 1-5,7-8,20,28,38,40-41 (Actual)

My goal was to add LTE bands 12-13, 17, 25-26, 28-30 & 41, but as you can see I was only successfully able to add bands 28 & 41. In particular, LTE band 17 is critical to AT&T Wireless in the U.S.

Does anyone understand why some bands were unable to be unlocked, even after setting lte_band_pref to allow pretty much anything? Are there additional NVRAM settings that I missed, or is this due to lack of support in the power amplifier? Does anyone even know the model of power amplifier used in this phone?