Wireless Joint

I've been having an issue with an EM7455 installed in a rugged computer/IoT device. For the last 6 weeks or so it's been up and connected to the Verizon (static IP) network in our office without so much as a single disconnect. We had it on 1-minute monitoring and it never dropped off even once.

We put it out in the field yesterday, connected to a Proxicast MIMO antenna. As usual with technical devices, it fooled me into believing it was working perfectly when it was installed. It connected the second the device booted and worked great -- until I got a good 2 hours away. And then it disconnected. So, I drove back that night and the computer was up, the modem displayed "Connected" in 'mmcli' but there was no Internet access. So, I used the most advanced tool in my arsenal, I rebooted the PC. It came right back up and reconnected. Not wanting to be fooled again, I sat with it. I waited. I stress tested, I speed tested, and it just kept right on working.

Until I was 2 hours away. And then it disconnected.

But, I had the last laugh, or so I thought. I had enabled a cron job to reboot the device every 3 hours. And just an hour later, it came back up. For 1 minute.

Anyway, it hasn't come back since. I'm going to have to go back to troubleshoot so I was hoping to get some advice of things to look at before I go out.

I'll look at AT!GSTATUS for levels on the main/diversity ports as well as other signal levels. I know it's got Verizon FW and PRI in it: 02.33.03.00, preferred carrier name: VERIZON, preferred config name: VERIZON_002.079_001

I read the Disconnect FAQ cover to cover, but a lot of these things don't apply because it was rock solid in our office for weeks.

Any expert advice? Should I try locking it to a band, could it be lost searching, should I load Generic FW? Any information I can collect to post here? Is there anything to watch live (log) to show what's happening?

Any help would be tremendously appreciated.
Thanks.

I am by no means an expert, but based on how you describe the issue I would suspect the problem lies with Verizon and not your setup. You proved it works in one location but not another. So if your signal strength is good at the new location the only thing else it could be is Verizon kicking you off.

Yes, I agree, I'm pretty confident that it isn't a hardware issue but its not a guarantee. I'd still rather be able to put my finger on exactly what the issue is. That's the engineer in me! And, I'm not an expert on these either, but if it's something like it's switching to something else for some reason (band, site, etc) and I can override that to make it stay put, well that's what I'd like to do.

I'm hoping there's some kind of live log or feedback that I can watch to see what's happening. But, when it wasn't connected last night ModemManager still showed "connected."

I am fairly certain there is no log of which bands/towers you are connected to and if they switch, or changing signal strength. For those all you can do is check and compare to previous times you have checked.