Unexpected channel activation

I’m using RN2903 and Kona Enterprise gateway which support only 8 channels (first 8).
I set the RN2903 to use only the first 8 channels, and I’m able to send data to the gateway and see it in the TTN UI,
But after few data transmissions the data rate change, and few unactive channels changes to be active.

I did set the gateway (in the TTN UI) to use frequency plan: US 902-928 FSB1
(at first, I set FSB2 but changed to 1 and the issue still accrue)

Any idea what can be the problem?
how to fix it ?


That is normal, and the minimum (for LoRaWAN). Some expensive more telco/enterprise grade systems occasionally have options for a 2nd concentrator module to add another 8, if supporting more bespoke frequency plans or band plans, so not a worry.

Where do you see that limit called out for the given fplan?

Rather than the option for FSB2 (as used for and recommended for TTN)? (I note your comment wrt 1st attempt.)

Devices and GW’s only change to the plans they are set for and under the control of the LNS. So best option (IMO) is stick with the TTN defaults (FSB2) and then try to diagnose what is happening rather than go none standard and battling through.

When setting the node fplan have you called out the full band plan channel set? Are you using ABP or OTAA? If you only told the LNS that you were setting mandatory channels it would command adding the additional channels which might mean if you have other elements set for FSB1 then it commands those…