An improved method for calibration of dynamic motion sensors. Such wafer chucks may include constraining members that are movable between open and closed positions. The sub pixels which form each of the virtual pixels include a sub pixel common to another of the virtual pixels. When the outgoing human speech is coupled to the DC control circuit by a first optocoupler and sent to another communication device and incoming human speech is transmitted from the other communication device via the DC control circuit and a second optocoupler, echoes and extraneous noise in the speech is reduced.