I know you are a true encyclopedia when it comes to APM and arducopter. I posted a question to the forum but did not get any answer. Below is my question.
After the ESC calibration all 4 motors on my Quadcopter behave very strange. When I arm them after booting the APM they start all together with ca. 1/4 power (I do not touch the throttle knob), work 4-8 secs and then all turn off. I can't then re-arm the motors anymore, have to hard-restart the board.
The radio is calibrated OK. Maybe the reason is that the calibration doesn't seem like in the description in the APS manual - when I start calibrating (throttle high) I listen sounds, the first four should be responsible for the throttle according to the HobbyKing ESC manual, when I then disconnect them and reconnect the battery, there is nothing happen - no sound, no possibility to arm.
When I try to move the throttle down after the four beeps, I listen two sounds but can't start the motors without disconnecting them from the battery first.
Before the ESC calibration there were no problems with the copter.