Hi Tom,
thanks for the reply. I already figured out how to do the setup described above, just waiting for better weather conditions to do a test flight. With my Pixracer manual is not only passthrough here, SERVO3_* and RC3_* change the output in manual flight mode too.
What I have done:
Set SERVO3_TRIM to 1500
Set THR_MIN to -25
With these settings it seems that it works as desired. Unfortunately in manual mode I could not set the throttle anymore, SERVO3 (PWM out to ESC) was fixed to 1500 irrespective of the throttle stick position. I could fix that by setting RC3_TRIM from 984 to 982. RC3_MIN is still at 984. If RC3_TRIM has the same value as RC3_MIN and SERVO3_TRIM is 1500 than it is not possible to set the throttle in manual flight mode (RC3 PWM out fixed to 1500), maybe that is a bug.
I will marked this as solved, hope to do the test flight this week.
Regards
Mirko