The invention relates to a metering device for fine grained powder, in particular for medicinal powder for pulmonary administration, and to a method for operating the metering device. An apparatus for measuring various characteristics of the DUT output signal includes a trigger generator for generating a series of trigger signal edges in response to selected DUT output signal edges occurring during separate repetitions of the digital signal pattern. By an amount by which the magnitude of the basic drive torque is suppressed, a target pinion angle computed by a target pinion angle computing unit decreases and a correction component for a basic assist component is decreased.