The present invention relates to a method and system for classifying biological specimen. The charging base recharges a battery of the remote control when the remote control is docked to the charging base. Data is transmitted at a data rate determined, at least in part, by the available output power. A controller is coupled to the phase detector and the driver circuit, and is configured to adjust a frequency of a source voltage applied to the driver circuit in response to an output signal of the phase detector.