I do not own one but looking at the documentation for the controller I noticed this, "gradual startup and shutdown of rotor power to reduce stress on towers, antennas and rotors. This is achieved by pulse-width-modulating the operating voltage for the rotor."
That could very well be the source of the "beeping" with the windings in the motor singing.
73 Kevin WA7FWF
On 3/26/2020 17:47, Jeff via AMSAT-BB wrote:
Green Heron R-21 controller