Abstract: Circuitry is described for detecting a waveshape having a change of slope, such as the optical signal wave from a nuclear explosion. The wave is amplitude-sampled at a rate determined by a variable frequency clock pulse generator. Signal pulses indicative of the slope of the wave are generated from the amplitude samples, and a certain number of the most recently generated slope signals are stored in a shift register. Majority logic circuitry, connected to the shift register, generates an output signal when the majority of the slope signals in the shift register changes from a first slope majority to a second slope majority.

Abstract: This disclosure is of an inverter type power supply including an actively switched damping circuit for limiting voltage transients in the inverter circuitry. Such damping is accomplished by switching an energy absorbing element into parallel circuit relationship with the inverter transformer during periods in which transients normally occur, the energy absorbed during these transients then being either dissipated or stored and later returned to the inverter transformer for improved circuit efficiency.

Abstract: A signal processor is described for pulse-echo systems such as sonar and seismographic systems in which wave energy is transmitted and received as a train of discrete pulses of different frequencies ordered in predetermined sequence. The receiver comprises a plurality of signal processing channels each of which selects one subpulse and delays it through an interval of duration inversely related to its time position in the pulse train, to thus bring the received subpulse signals into time alignment so that when added their summed amplitude constitutes the target signal output. For interference level compensation, a running estimate is made of the interference level in each of the signal processing channels, and the channel signals then are weighted by this interference estimate as an inverse function of its magnitude.