A generator including: a housing having an opening; a rotatable member having a slot formed for an angular length less than 360 degrees; a cable disposed in the slot and having a free end protruding from the opening in the housing; a cable stop disposed in a predetermined position in the slot; a spring for storing energy as the cable is unwound from the slot by pulling on the free end until the rotatable member rotates relative to the housing and the cable stop aligns with the opening; and an electromagnetic generator operatively connected to the spring such that the stored energy of the spring is transferred to an input side of the electromagnetic generator.