TRB500 - instable connection - 5G NSA

[Dennis]

Hi,

I am having connectivity issues with my newly acquired TRB500. Internet connection is unstable and I loose a lot of pakets.

It has two Poynting XPOL-2-5G antennas connected to it via 5m cables. Antennas are outside pointing to the same direction at a tower that supports B1, B3, B20, N28, N78 Bands - roughly 900m away.
Provider is O2 Germany.

If I use the provided antennas, that came with the package I still have an instabile connection.

I am using the latest firmware for this product:

Can you help me figure out, what is causing this bad connection?
The 4G bands seem to be disturbed. According to the tower and provider information, 5G SA should be available. Is there a way to select 5G-SA in the device, to avoid 4G band issues?

I would be glad, if you could point me into the right direction.

Kind regards,
Dennis

[Daumantas]

Hello,

In order to force the device to connect to 5G-SA, please use the following command:

gsmctl -A 'AT+QNWPREFCFG= "mode_pref",NR5G'

If you’d like to set the device to 4G+5G, use the following command:

gsmctl -A 'AT+QNWPREFCFG= "mode_pref",LTE:NR5G'

Lastly, if you’d like to go back to AUTO, use the following:

gsmctl -A 'AT+QNWPREFCFG= "mode_pref",AUTO'

To run these commands, use CLI available via the GUI or SSH. More information is available here: Command Line Interfaces RutOS - Teltonika Networks Wiki
Let me know if this helps.

Best regards,

[Dennis]

Dear Daumantas,

thank you for your fast reply. The mode preference worked, but unfortunately TRB500 was not able to establish a connection and got reset to 5G+4G.

In any case can you help me with the instable connection? I have lots of packet loss…
Eg. here you see a recording of the current WAN address via an check-IP of AWS:

The connection gets reset and the grey bars are failed tests - because of packet loss…

Here is a graph with packet loss:

In the past I had 0% packet loss.

I have a hard time interpreting the results using various antenna configurations.
all provide an instabile connection, there is no improvement.

Is this a fault at the provider/cell tower? Is it a problem on my side with the signal?
Why is only one band with good signal and the other with no signal in regards to SINR?

Thank you for your support!

Best regards,
Dennis

[Daumantas]

Hello,

It seems like only Deutsche Telekom supports 5G SA in Germany, other carriers do not yet.
While it’s hard to say for sure, packet loss is usually caused by either a weak signal, cell tower load, or simply too weak backbone on the carrier side.
In this case, while the signal is not ideal, it should not cause any issues.
To verify that the issue is not related to the device itself, could you try a hard reboot (unplug and replug the device back in) and check if the packet loss remains the same? If it does, then the issue is likely with the carrier.
Also, would it be possible to monitor multiple hosts for latency and packet loss? E.g. checking packet loss to Google (8.8.8.8) or Cloudflare (1.1.1.1) DNS?

Best regards,