@guillermo-schimmel Thanks a lot ! I got it all up and running node a couple of nodes. But now I confused myself . I got an Arduino Nano as a node that also acts as a repeater, what bootloader can I push into that one? I assume anycahnnel and 16MHz should do the trick since it got that crystal attached. And also one thing that is not really clear in my head, I set the "Fuses&Lock bits" with the AVRDudess for my 328P barebone. But do I really need that? . If I load the bootloader in ARduini IDE for example I specify all those settings in the "board.txt" file. Or is that just to tell the IDE what settings is on the chip ? If I clear these two things up I think I got everything sorted now