Issue with CA. Any way to disable?

[mattvds]

Howdy Folks,

Up until a few days ago, everything was humming along well with Sprint. Then all of a sudden I started getting a lot of packet loss/drop-outs. After some trouble shooting it appears that this is only happening when CA is enabled. B25 and B26 work fine, and B41 works fine until it enables CA.

First of all, does anyone have any idea on what would cause CA to have so many issues? My thoughts are that it is either something wrong with the tower (unlikely), or something wrong with my 2nd antenna, MC7455 or cables (more likely).

Right now I've locked my modem to B25, but non-CA B41 is still substantially faster, so I'm wondering if there is a way to disable CA on the modem itself? Unplugging the 2nd antenna doesn't achieve this, as it still quickly upgrades itself to CA and then the problems start up again.

Thanks!

[JimHelms]

The second antenna is for diversity and allows for MIMO. It is not required for Carrier Aggregation.

That is not to say that a bad or loose connector or antenna could still not be causing an issue. But, it is possible it is carrier related. Sprint is doing a lot of software upgrades on their network, and you are not the only one having issues in various locations.

I had a similar issue on one certain tower that has never given problems before. I went to two other towers and everything was fine. I took almost a week before the tower issues cleared up.

So, if I were you, I would check my connections and if all looked okay, I would give it a few days before I started chasing a problem that is not within your reach to fix.

[danielewood]

You are only going to degrade things by removing the second antenna.

As it happens, I discovered an undocumented (just a mention of its existence in a change log ) AT command for the 74xx series last week that is exactly what you are looking for.

Code: Select all

AT!LTECA?
Hardware:
LTEB1: B8, 
LTEB2: B2, B5, B12, B13, B29, 
LTEB3: B7, B20, 
LTEB4: B4, B5, B12, B13, B29, 
LTEB5: B2, B4, B30, 
LTEB7: B3, B7, B20, 
LTEB8: B1, 
LTEB12: B2, B4, B30, 
LTEB13: B2, B4, 
LTEB20: B3, B7, 
LTEB25: 
LTEB26: 
LTEB29: 
LTEB30: B5, B12, B29, 
LTEB41: B41,

Permitted Bands:
Empty

Prune_ca_combos:
Empty

AT!LTECA=?
!LTECA=<flag>
<flag>: 0 – disable CA
	1 – enable CA

[mattvds]

Thanks for the replies, and for the education on MIMO, for some reason I thought it only mattered with CA.

Appears it was a tower issue, as I just when I was about to switch back to B41 and disable CA with the commands you posted, B41 w/ CA is back in great working shape. Figures as soon as I figure out a way to work around it, it fixes itself .

I've also ordered myself another modem and router setup, which I'm planning to have setup as a dedicated connection for my nest cams and also hoping to figure out how to use it as a fall back when the primary connection goes on the fritz, which happens more than I'd like, probably because I have relatively bad Signal strength here. Anyone have experience or recommendations on the optimal way to set this up?

[mattvds]

Did some research this evening, and ended up ordering a used mushrooms networks truffle router. In theory it will bond the connections together for HTTP requests, support load balancing, and failover. I picked it over the PepLinks because it offered the bonding, versus just the failover. We will see how well it works.