clock

i need a ckt to produce a flip flop output -square wave (30% duty cycle) with 3V or 1.5 V. input to my required ckt is from a pulse generated by a moving magnet to and fro over a static coil. this is similar to pendulum movement in wall clocks. The pulse output is 300 to 400 mV with 1 Hz frequency. can somebody help me by sending a suitable circuit. if you need any further information. i'll provide. clock