Abstract: A circuit for providing controlled switching of power applied to a load is adapted for actuating and deactivating a power switching circuit in response to a command signal. The circuit employs a switching circuit having a time delay section operable to terminate application of power immediately upon the cessation of a control signal and to conduct current after a predetermined delay interval after receipt of a command signal. The circuit is adapted for use with pyrotechnic ignition systems in which it is desired to quickly discharge capacitive elements connected to a load for prevention of undesired and possibly hazardous build-up of heat in a resistive ignition element.

Abstract: A parachute release arrangement which is mounted on the parachute buckle lizes a pair of water sensors that are activated when they are immersed in sea water. Activation of one sensor results in the connection of a battery to a DC-to-DC converter which raises the battery voltage to a substantially higher level for charging a storage capacitor. If the other sensor is also activated, this storage capacitor is subsequently discharged through an electrical explosive device when the voltage across it reaches a predetermined value. The resultant explosive force disengages a release lever in the buckle from the parachute strap and allows the detachment of the parachute. A checkout circuit is provided for monitoring the standby status of the control circuit.

Abstract: A power controller for transmitting alternating current from a power input circuit to a load, the controller being a master silicon controlled rectifier, hereinafter the "master rectifier," and a slave silicon controlled rectifier, hereinafter the "slave rectifier," connectible in parallel with the load across the input circuit, a capacitor chargeable during positive half cycles for discharging at the zero voltage crossover between half cycles of positive and negative input voltage to render the master capacitor conductive and a second capacitor chargeable When the master controlled rectifier is conductive whose discharge renders the slave rectifier conductive at the instant of zero voltage crossover between half cycles of negative and positive input voltage.