"Thanks for the answer, Ken. I just re-soldered it, but without any success. What exactly is the channel 3 on the board? I hope one of them I used :)
http://www.die-kreuzzuege.de/P1000440.JPG
Still no changes on the LED. Whatever position I move the…"

"The LED is really supposed to blink? Mine stays on all the time and this is the second encoder I tried (sent back the first one because I thought it might be damaged). Is this the right way to connect it? I can't find any documentation :) I tried…"