Abstract: A firing circuit for use in booby traps providing four different operatio modes. A capacitor stores energy which is discharged through an electrical detonator upon the activation of a silicon controlled rectifier. The silicon controlled rectifier is activated by transistor circuitry in the event of supply voltage depletion or the physical parting of a break-wire by a target. It is also activated by a delay-timer for timed self-destruction and by circuitry responsive to vibrations in the firing circuit generated by the target.

Abstract: A system for mooring a buoyant case such as a marine mine or other marine vice at a preselected depth below the surface of the water in which the case was launched. After the case has been launched, together with an attached anchor, the anchor and case separate to the extent of a resilient line as they descend through the water. When the case passes through a first preselected depth the resilient line is released from the case, thereby permitting a mooring line, which is connected in series between the resilient line and the case, to payout. As the mooring line unwinds the anchor descends to the ocean floor while the buoyant case ascends toward the surface. When the case ascends through a second preselected depth a brake assembly is activated to stop the payout of the mooring line. After the case has been positioned at the second depth, a locking assembly fixes the position of the case at the mooring depth.

Abstract: Apparatus for automatically controlling the mooring depth of a submerged yant body secured to an anchor by a mooring line contained within the anchor having a power supply, a first potentiometer preset to a desired mooring depth and variable with the payout of mooring line, a second potentiometer variable with ambient water pressure for sensing the depth of the anchor, and a null detector connected between the slidable taps of the potentiometers and a mooring line payout control system for actuating the payout control system if there is an unbalance therebetween in one, but only one, direction.