No uplink received with WaziHat (low signal)

[cdupont]

I am trying with the WaziHat V1.3, RPI3, ISO 2.1.1.
I send messages with WaziDev and this sketch: https://github.com/Waziup/WaziDev/blob/master/examples/LoRa/LoRaWAN_LPP_LMIC/LoRaWAN_LPP_LMIC.ino

However the messages are not received with WaziHat.
Logs:

2020-12-11T17:19:46.428623470Z Initiating the single-channel Lora packet forwarder...
2020-12-11T17:19:46.428680448Z 
2020-12-11T17:19:46.428735864Z ============================
2020-12-11T17:19:46.428791489Z 
2020-12-11T17:19:46.428847270Z 
2020-12-11T17:19:46.428903988Z Restarting the CE0 pin...
2020-12-11T17:19:46.428989456Z ./start.sh: line 68: echo: write error: Device or resource busy
2020-12-11T17:19:48.425847856Z Done
2020-12-11T17:19:48.426071135Z 
2020-12-11T17:19:49.430900240Z Restarting the RFM95x Module...
2020-12-11T17:19:50.238629994Z ./start.sh: line 79: echo: write error: Device or resource busy
2020-12-11T17:19:50.443006195Z Done
2020-12-11T17:19:50.443237599Z Launching the forwarder...
2020-12-11T17:19:51.467533320Z ln: failed to create symbolic link './global_conf.json': File exists
2020-12-11T17:19:51.816936252Z [     ] listening on [::]:48759
2020-12-11T17:19:51.818566183Z [     ] (-> 172.18.0.7:1700) PullData: Token: E3F7, Gateway ID: AA55A00000000000
2020-12-11T17:19:52.122527674Z [     ] radio SX1276 activated.
2020-12-11T17:19:53.554567475Z [ERR  ] Can not set output power: expected 0xe, got 0xfc
2020-12-11T17:19:53.912081675Z [     ] waiting for packets ...
2020-12-11T17:20:20.493781568Z [     ] (<- 172.18.0.7:1700) PullAck: Token: E3F7
2020-12-11T17:20:51.766954504Z [     ] (-> 172.18.0.7:1700) PullData: Token: BB4F, Gateway ID: AA55A00000000000
2020-12-11T17:20:51.767273615Z [     ] (<- 172.18.0.7:1700) PullAck: Token: BB4F
2020-12-11T17:21:51.766101136Z [     ] (-> 172.18.0.7:1700) PullData: Token: 5478, Gateway ID: AA55A00000000000
2020-12-11T17:21:51.766946023Z [     ] (<- 172.18.0.7:1700) PullAck: Token: 5478
2020-12-11T17:22:51.766266456Z [     ] (-> 172.18.0.7:1700) PullData: Token: DE5D, Gateway ID: AA55A00000000000
2020-12-11T17:22:51.766996448Z [     ] (<- 172.18.0.7:1700) PullAck: Token: DE5D
2020-12-11T17:23:51.766475056Z [     ] (-> 172.18.0.7:1700) PullData: Token: 5ECD, Gateway ID: AA55A00000000000
2020-12-11T17:23:51.775344753Z [     ] (<- 172.18.0.7:1700) PullAck: Token: 5ECD
2020-12-11T17:24:51.766873186Z [     ] (-> 172.18.0.7:1700) PullData: Token: 7516, Gateway ID: AA55A00000000000
2020-12-11T17:24:54.494409142Z [     ] (<- 172.18.0.7:1700) PullAck: Token: 7516
2020-12-11T17:25:51.766535177Z [     ] (<- 172.18.0.7:1700) PullAck: Token: 4AF9

[cdupont]

Raising the SF to 12 on WaziDev gives better results.
https://github.com/Waziup/WaziDev/blob/master/examples/LoRa/LoRaWAN_LPP_LMIC/LoRaWAN_LPP_LMIC.ino#L26

However the signal is still very weak: RSSI -89dBm (very weak signal).