A pulse signal generator using a magnetic device that can cause a large Barkhausen effect, comprises means having a number of pits and projections and generates pulses according to the behavior of these, the means being capable of moving the pits and projections in a first or second direction, the pits and projections being disposed in the moving direction with some of the projections missing or some of the pits filled. The value of the ratio between the time interval of pulses generated by portions other than a projection-missing portion and the time interval of pulses generated by the projection-missing portion or the value of the ratio between the time interval of pulses generated by portions other than a pit-filled portion and the time interval of pulses generated by the pit-filled portion differs between when the pits and projections move in the first or second direction.