In this short video, I am showing how to calibrate the gyro (flight control board) as well as set up the internal trims for a level and steady hover this was previously called the secret mode setup only because the manual did not explain it and I had to learn this direct from the factory engineer.
This procedure is shown for the C190 model but it’s applicable to other RCERA helicopters, including the C186, C187, C189, C123 and C129V2 models.