Page 1 of 1

MR6400 not respecting 5G band selected

Posted: Wed Jan 04, 2023 9:45 pm
by igorjrr
Carrier: T-Mobile.
Device: MR6400, already unlocked and TTL set.

I can see in the admin site that it first connects to NR5G N71, then in a second goes to LTE B2 (or B66 sometimes). Speed in B2 is like 17 Mbps, and better in B66 (like 30 Mbps). The interface does not have a band selection, it simply shows Auto and does not have anything else.

If I insert SIM in a T-Mobile Home Internet Arcadyan KVD21, in the T-Mobile Home Internet app it shows LTE B66 and 5G N41. Speeds are great (like 120 Mbps).

I even tried to spoof KVD21 IMEI in MR6400, but same results.

I don't understand why MR6400 is falling from 5G to slow LTE band. I expected it would actually provide even better service than the gateway, in choosing bands.

I was able to create band groups, and when I put 5G only, it connects to 5G. However, it is not respecting the specific 5G band I chose.
For example, I tried: AT!BAND=02,"5G N41",0,0,0,0000010000000000,0,0
However, in the interface it always show 5GNR N71. The gateway connects to N41 and it's fast, but MR6400 seems to be connecting only to N71.

Any idea?

Re: MR6400 not respecting 5G band selected

Posted: Mon Jan 09, 2023 9:13 am
by Didneywhorl
Just making sure, but are you setting the band mask after you define it?

The command you posted above only defines the band mask, you still have to set it with AT!BAND=02

This is assuming it took your defined mask, which you can check with AT!BAND?

Re: MR6400 not respecting 5G band selected

Posted: Mon Jan 09, 2023 4:38 pm
by igorjrr
Didneywhorl wrote: Mon Jan 09, 2023 9:13 am Just making sure, but are you setting the band mask after you define it?

The command you posted above only defines the band mask, you still have to set it with AT!BAND=02

This is assuming it took your defined mask, which you can check with AT!BAND?
Yes, tried selecting the band via AT and also via interface (my defined bands show up).

Re: MR6400 not respecting 5G band selected

Posted: Mon Jan 09, 2023 11:44 pm
by Didneywhorl
That is odd that it's showing you the bands, I'm guessing the Nighthawk is different than the normal Sierra 5G band locking?


For the regular Sierra modems it would be:

For SA n41, your command should be:
AT!BAND=0D,"5G SA N41",4,0000010000000000,0

NSA would be:
AT!BAND=0D,"5G SA N41",3,0000010000000000,0

Also, 02 is the stock band group for the North America 3G bands. I would start my band groups from 0D and above.