APPARAT FOER FREKVENSSTUDIER UTNYTTJANDE HAOLKORT ELLER HAOLREMSOR

摘要

An apparatus for performing frequency studies by employing punched cards includes a randomly occurring impulse generator wherein each impulse initiates an alerting signal. The alerting signal indicates to an operator that he should punch the card at a position indicated by the one of a plurality of lamps which is energized by a stepping device. When the operator punches the card, a circuit means terminates the alerting signal thereby ending the recording cycle.