@alowhum thank you

@gohan Indeed... See e.g. my experience here: https://forum.mysensors.org/topic/2890/chinese-rubbish-or-is-it

@Boots33 Thanks for advice! I will definitely get some extra non amplified nrf modules and think about having a separate power supply for my radio.

Thank you both for your answers. With so many parameters to play with, it was not easy to understand what was wrong.. But I think I finally got a way do get my hardware working Here are my findings : I thought I got RFM73 version of NRF24-like radios. They look like like here and here. After checking and connecting all VCC and GND together, switch radios and arduinos... I got them suddenly working with Mysensors development librairies, then back to silence without apparent reason... Indeed like @mark_venn suggested, I went back to stable librairies and try so set a static ID. Worked well... until it went back to silence again ! Then, following @mfalkvidd advice, I realised that flashing the eeprom_clear sketch solved my all my problems ! My summary : Ensure that your 3.3V power supply is strong enough. Ensure that your arduino, radios and sensors are sharing the same GND and VCC. Use development librairies from github Flash eeprom_clear before flashing your mysensor sketches Then gatewaySerial and relayActuator should be able to communicate "out of box", mean you'll monitor some lines like this on the gateway serial : 0;255;3;0;9;read: 0-0-0 s=255,c=3,t=15,pt=0,l=2,sg=0: Thanks again for your help, now I can start to play

Thanks for the tip!. It looks like a USB powered Arduino Nano cannot handle the long range radios power requirements. I powered the radio module independently and I can send commands succesfully again! The range has not improved, though, but that's another matter... Thanks !

@jaumard Dont think this is very nice to RFXCom dont you think? Besides, that you can decode a 'few' protocols, do you really think you can decode all that RFXCom does? What is expensive ? 100 euro's for a rock solid (and active developed) device ? Did you looked at the 'RFLink' project?

@AWI thanks for pointing me to the doc it look great ! I will give it a try

@hek Just a hunch, could it be the radio that somehow is stuck in receive mode, and not going to sleep? If I remember correctly from the datasheet, it almost uses the same current in both transmit and receive mode (~14mA) / Thomas