Dear malo, thanks a lot for your used modules. No, I haven't got a sniffer up to now. I think this is the next step for me - set up a sniffer to find faults in the radio transmission. At the moment I'm lucky because UDP transfer works at the moment. It was just a quick check and real testing is the next step but getting it running was a big success this weekend. By the way: I have also a Beaglebone-Green running with a 4.1.14 mainline kernel and a Microchip MRF24J40MA radio device and it works as well. Wonderful! Thank you very much! Best regards, Bernhard