You want to do the throttle calibration on the RX that you plan to use. Just unplug all other servo leads including the power from a FC PMU and allow the ESC BEC to power the RX during the Calibration through the throttle channel being calibrated.
I have always been confused by this. Can you tell me where I'm going wrong here?
During actual use, the RX from the radio is connected to the flight controller. The controller is connected to the ESCs. The flight controller is making all sorts of decisions about how much power to send to each motor in order to maintain attitude, etc., and the control signals from the RX never reach the ESC in raw form (at least on every flight controller I've seen). So I don't understand the point of calibrating ESCs to the RX.
Taking this a bit farther, the calibration merely moves the end points on the ESC -- i.e., tells the ESC what the minimum and maximum are for the throttle signal (literally the PWM signal widths). With the top end throttle position being relatively irrelevant, the primary point of all of this is to adjust the bottom end, and that in turn is aimed at the throttle level that starts the motors (the minimum PWM signal width required to get the motors started, which is a bit more than the low end throttle position). But flight controllers, in my experience, do not start motors by sending raw RX throttle values to ESCs. Rather, a start sequence from the RX tells the flight controller to start the motors and the controller then sends its own start value to the ESCs.
So, why does it matter which RX is used to calibrate ESCs, and more importantly why calibrate at all?
