@mfalkvidd
I was to quick, it was working so I used it to solder a PCB. That did not work, so tested again on a breadboard. Now it did not work. So I tried:
4.7
22
33k
47
47+22
Both on the breadboard and directly connected, not with power from the batteries and from the arduino, but it not work. He never gets a reply back.
So it has worked, but know it doesn’t, when I connect a stable powersupply it works.
What else should I try?