Abstract: A threshold selection circuit, suitable for a processing unit for the processing of video signals obtained from an angle tracking device, is provided with a number (N) of video integrators to receive video signals above certain threshold levels decreasing in numerical order, and with a weighting network, connected to the video integrators, for selecting and assigning the threshold of the lowest numbered video integrator for the processing unit, of which video integrator the output signal does not exceed a fixed fraction of the output signal of the video integrator operating with the next lower threshold.