i tried this . doesnt work.
but i managed to find out some data. with this code: lordvon's stuff: Getting PWM frequency and duty cycle with Arduino
the serial port gave me 47.23 and 50.64 out. the values vary.
so the frequency is 50 Hz and duty cycle 47 %. that would correspond because i already received a 9,3 ms signal. so the period would be 20 ms.
Could this be correct?