Abstract: 1. A detonating circuit comprising a coil responsive to an external magne field, a vibration responsive switch connected in parallel with said coil having a closed position and an open position, said switch responsive to external vibration for vibrating between said open and closed positions, an electronic amplifier coupled to said switch and to said coil and biased to provide constant amplitude pulses having periods equal to the vibration rate of said switch, an impulse forming circuit coupled to said amplifier having means for storing a predetermined number of said pulses, an explosive primer, means coupled to said impulse forming circuit and to said primer for actuating said primer when an impulse of predetermined energy is generated in response to the receipt of said predetermined number of pulses.

Abstract: 1. An inertial switch comprising a cylinder, a cap secured to one end of d cylinder, said cap having a central bore therethrough running parallel to said cylinder and a transverse hole communicating with said bore a wire inserted in the hole in said cap; a shearing member mounted in the bore, having a hole in which said wire is inserted and having a portion extending into the interior of said cylinder; a coil spring located within said cylinder having one end contacting said cap; a base secured to the other end of said cylinder; and a piston contacting said spring and base and having an elongated central portion; said spring being relatively long compared to the length required to stop the elongated portion of said piston from striking the portion of said shearing member extending into the interior of said cylinder when the switch is dropped from a distance of 40 feet onto a steel plate, whereby said wire is broken only when a predetermined sufficient energy is imparted to said spring.

Abstract: 1. A vibration responsive switch comprising a mass, a pair of support strures located on opposite sides of said mass, a taut wire attached to both of said support structures and to said mass, a switch armature mounted on said mass, and a fixed contact located in physical proximity to said armature.