The Things Node does not send uplink data

[arjanvanb (Arjan)]

@lso

The RSSI seems very low (fluctuates between -117 and -121), but as it is receiving its activation request, i am not sure that this is a problem.

Just to be sure: the RSSI you see is that for the OTAA Join Request (orange icon), as sent by the node and received by one or more gateways. (Probably one gateway as you’re only mentioning one RSSI.) If you have access to gateways logs (like in TTN Console) then you’d also see the OTAA Join Accept being sent (green icon). You cannot see the RSSI for the Join Accept, but most likely the node has not received that, and keeps retrying.

So, you need a better reception (take the node outside; increase its height?), or need to try at a lower data rate (higher SF):

@arjanvanb

In the TTN library you can change the default SF using the constructor’s optional parameters :

TheThingsNetwork ttn(Stream& modemStream, Stream& debugStream, fp_ttn_t fp,
   uint8_t sf = 7, uint8_t fsb = 2);

As an aside: as TTN assigns a DevAddr, it has accepted the Join Request, so the settings in the device match the settings in TTN Console (DevEUI, AppEUI, AppKey).