Wireless Joint

Posted: **Sun Feb 26, 2023 2:45 pm**

So T-Mobile has recently turned on band n25 and n41 all over the place in my area. My Galaxy 23+ connects to n25 and n41 just fine and I can see all the network info when I go into the service mode on the Galaxy 23+. Naturally I wanted to get my EM9191 running on n25 and n41 as well. On the Sierra Wireless website it is listed that n25 is a 5G band that the EM9191 is capable of using. However, when I go into the AT commands and list out the available bands, n25 is nowhere to be found. How would I go about getting n25 working on EM9191? I tried manually adding the n25 band mask and that did not work, AT command just kept return "ERROR". I've done band locking in the past with NR-5G SA and NSA modes with success, but the modem just doesn't have n25 as an option or for me to add it. I'm wondering if there is a different firmware I need to flash to the modem in order to use n25 but I'm not sure what firmware version that would be. Any help is appreciated.

Another thing I'd like to add, I can not force the modem to connect to just n41. It would seem that T-Mobile is using n25 on this particular tower as the main carrier band and n41 as the secondary band.

EM9191 Band Specs.JPG

EM9191 running below listed firmware version

Code: Select all

AT!IMPREF?
!IMPREF: 
 preferred fw version:    03.09.14.00
 preferred carrier name:  GENERIC
 preferred config name:   GENERIC_030.047_000
 preferred subpri index:  000
 current fw version:      03.09.14.00
 current carrier name:    GENERIC
 current config name:     GENERIC_030.047_000
 current subpri index:    000

OK

EM9191 Available Bands

Code: Select all

Available:
0 - GW:    
     1000000000000000 - B19 (850)
     0004000000000000 - B9 (1700)
     0002000000000000 - B8  (900)
     0000000008000000 - B6  (800)
     0000000004000000 - B5  (850)
     0000000002000000 - B4 (1700)
     0000000001000000 - B3 (1700)
     0000000000800000 - B2 (1900)
     0000000000400000 - B1 (2100)
1 - LTE:   
     1/0000800000000000 - B48    
     1/0000200000000000 - B46    
     1/0000020000000000 - B42    
     1/0000010000000000 - B41    
     1/0000008000000000 - B40    
     1/0000004000000000 - B39    
     1/0000002000000000 - B38    
     1/0000000200000000 - B34    
     1/0000000080000000 - B32    
     1/0000000020000000 - B30    
     1/0000000010000000 - B29    
     1/0000000008000000 - B28    
     1/0000000002000000 - B26    
     1/0000000001000000 - B25    
     1/0000000000080000 - B20    
     1/0000000000040000 - B19    
     1/0000000000020000 - B18    
     1/0000000000010000 - B17    
     1/0000000000002000 - B14    
     1/0000000000001000 - B13    
     1/0000000000000800 - B12    
     1/0000000000000080 - B8     
     1/0000000000000040 - B7     
     1/0000000000000010 - B5     
     1/0000000000000008 - B4     
     1/0000000000000004 - B3     
     1/0000000000000002 - B2     
     1/0000000000000001 - B1     
     2/0000000000000040 - B71    
     2/0000000000000002 - B66    
3 - NRNSA: 
     1/0000010000000000 - n41    
     1/0000000008000000 - n28    
     1/0000000000000010 - n5     
     1/0000000000000004 - n3     
     1/0000000000000002 - n2     
     1/0000000000000001 - n1     
     2/0000000000004000 - n79    
     2/0000000000002000 - n78    
     2/0000000000001000 - n77    
     2/0000000000000040 - n71    
     2/0000000000000002 - n66    
4 - NRSA:  
     1/0000010000000000 - n41    
     1/0000000008000000 - n28    
     1/0000000000000010 - n5     
     1/0000000000000004 - n3     
     1/0000000000000002 - n2     
     1/0000000000000001 - n1     
     2/0000000000004000 - n79    
     2/0000000000002000 - n78    
     2/0000000000001000 - n77    
     2/0000000000000040 - n71    
     2/0000000000000002 - n66    

OK

Posted: **Mon Feb 27, 2023 1:59 pm**

Might need to use the Tmobile one specifically: https://source.sierrawireless.com/resou ... -packages/

I don't know why you would have to, but that is for sure odd.

I'll test mine when I get a chance.

Posted: **Fri Mar 03, 2023 10:01 am**

Turns out that won't help and here's why.

Old EM9190 SKU: 1104567
Old EM9191 SKU: 1104629
This modem will not have all the bands that are advertised. The affected bands are as follows: LTE B43, 5G NR n7, n8, n12, n20, 25, n38, n40, n48

New EM9190 SKU: 1104902
New EM9191 SKU: 1104903
New EM919x SKUs add support for additional bands:
LTE B43, 5G NR n7, n8, n12, n20, 25, n38, n40, n48

Directly from Sierra Wireless
Existing SKUs:
o Will continue to be calibrated as they are today (in order to remain consistent with existing customer platform certifications).
o Cannot be field updated to add the necessary calibration data to enable the additional bands.
o Will operate with the band support they have with Release 1 firmware when upgraded to Release 2+ firmware. (additional bands are not supported)

Here is the official "TSB" from Sierra Wireless.

SIERRA WIRELESS EM9191 PRODUCT BULLETIN.pdf

Wireless Joint

EM9191 Band n25 Not Available

EM9191 Band n25 Not Available

Re: EM9191 Band n25 Not Available

Re: EM9191 Band n25 Not Available