Abstract: An output one-shot including a monostable multivibrator having a source of ositive voltage connected through a network of inductive, resistive and capacitive elements. A transistor receiving a power source through a decoupling network is connected to the network and the monostable multivibrator for providing increased stability to the system.

Abstract: An airborne system for automatically and electronically recognizing and dcting the relative presence of invariant features of a transient submarine signal occurring in the presence of signal-like noise. A plurality of comb filters receive MAD signal information in the amplitude-time domain and filter it to provide amplitude-time-frequency domain information. The primary features (positive and negative slopes) of this latter information are then abstracted, the abstracted information being utilized in a signal processor to detect and recognize the relative presence of invariant, submarine recognition features. Upon recognition, a decision thereof is routed to a visual display.

Abstract: A system for ascertaining the bearing of a remotely-located acoustic signal ource including a hydrophone array having an omnidirectional hydrophone and a pair of orthogonally-oriented directional hydrophones all of whose output signals are applied to a processor which combines the output signals of the directional hydrophones to provide a signal shifted in phase relative to the omnidirectional output signal by an amount equal to the bearing angle and which resolves the phase-shifted signal by phase detection into a pair of signals representative of the sine and cosine of the bearing angle. The sine and cosine signals are processed by integrators and a bearing angle computer to provide an output signal indicative of the bearing angle to a display. A second embodiment of the processor combines the directional hydrophone output signals into a pair of phase shifted signals for resolution, one leading and the other lagging the phase of the omnidirectional signal by an amount equal to the bearing angle.

Abstract: Apparatus for determining the bearing of a remotely located source of an inging acoustic signal including a sonobuoy having a submerged package including a hydrophone array for producing omnidirectional and orthogonal directional signals, a combiner for combining the directional signals, and a single channel multiplexer including modulators and a compass driven resolver for providing a single channel multiplexer output signal carrying bearing information in a single frequency channel via a cable to a transmitter unit carried by a surface package of the sonobuoy. The transmitter unit transmits the single channel multiplexed information to a receiver whose output signal is applied to a demultiplexer for deriving a pair of phase shifted signals indicative of the omnidirectional acoustic signal received which pair have a relative phase shift equivalent to the bearing angle referenced to magnetic North.