I still had to get back to 2x for setting by pressing the tiny "reset" button. Indeed, I had chosen the first of 4 available functions namely wifi amp. It does not match my use.
I, the second time, chose the wireless router function that option enables a second name to wireless network in the room.
This case perfectly matches my expectations, ie, connect the TV in my room ethernet. The cable, however, is much too short for that, unfortunately.
In summary, quality / great price but I take one star for too short cable and illegible documentation.