Abstract: A highly-amplified pickoff signal responding to positional deviations of a wire-suspended gyro are fed to a torquer connected to the gyro. In response to these the torquer exerts on the gyro a torque counteracting the gyro directing torque. The pickoff signals are sampled at time internals T and an analogue-digital converter produces therefrom a timed sequence of digital signals with each digital signal being proportioned to the pickoff signal at a time of sampling. This sequence of digital signals are fed to a digital filter which produces an output signal, indicative of the deviation, in accordance with the equation:U.sub.M (nT) = U.sub.M ((n-1).multidot.T) +1/n [u.sub.m (nT) - U.sub.M ((n-N).multidot.T]wheren is a consecutive whole number,U.sub.M (jT) the average value output at the time jT,u.sub.m (jT) the digitalized measuring value at the time jT, andN a fixed whole number.