Abstract: Apparatus for locating an acoustic source which includes a pair of gradient microphones each of which is adapted to receive an acoustic wave on one axis with the two axes of the microphones being orthogonal to one another. Processing means are included for receiving first and second signals from the two gradient microphones in comparing the phase of the two signals, whereby alarm means are provided for producing a signal identifying a change in state of the phase comparison. Upon the change in state of the phase comparison, from either mutually in phase or mutually out of phase with one another, the point of closest proximity to the sensor is determined.

Abstract: A compressor fault detection and control system for a reverse cycle refrigeration system for detecting faulty compressor operation and for controlling the system in response to the detection of a fault by inhibiting the compressor and for providing a fault indication, the control system comprising a controller means receiving inputs indicative of the outdoor air temperature, the temperature of the compressor discharge refrigerant, and an output indicative of a demand from a building temperature sensing means for heating or cooling of the building. The controller means also includes timing means and means for comparing the value of the compressor discharge temperature and the value of the outdoor air temperature.

Abstract: A compressor crankcase low differential temperature detection and control system for a reverse-cycle refrigeration system for detecting an abnormally low temperature crankcase and for controlling the system in response to such fault detection by inhibiting the operation of the compressor and for providing a fault indication.

Abstract: A compressor start fault detection and control system for a reverse cycle refrigeration system for detecting faulty compressor startup operation and for controlling the system in response to the detection of a fault by inhibiting the compressor and for providing a fault indication, the control system comprising a controller means receiving an input indicative of the temperature of the compressor discharge refrigerant and an output indicative of a demand from a building temperature sensing means for heating or cooling of the building.

Abstract: A loss of refrigerant and/or high discharge temperature detection and control system for a reverse cycle refrigeration system by providing a fault indication whenever the temperature of the compressor discharge refrigerant is at or above a predetermined value (which value is a function of the magnitude of the outdoor air temperature) and which functions further by inhibiting the operation of the compressor of the reverse cycle refrigeration system whenever the temperature of the refrigerant at the compressor discharge exceeds a predetermined value above which the compressor would be damaged if it continued to operate.

Abstract: An improper or wrong operational mode fault detection and control system for a reverse cycle refrigeration system for detecting faulty operation, i.e., operation in the cooling mode when heating is desired or in the heating mode when cooling is requested, and for controlling the system in response to the detection of a fault by inhibiting the compressor and for providing a fault indication, the control system comprising a controller means receiving inputs indicative of the outdoor air temperature, the temperature of the outdoor heat exchanger coil refrigerant, and an output indicative of a demand from a building temperature sensing means for heating or cooling of the building. The controller means also includes timing means and means for comparing the value of the outdoor heat exchanger coil refrigerant temperature and the value of the outdoor air temperature.

Abstract: A control system for a reverse cycle refrigeration system for controlling the defrosting of the outdoor coil thereof on a cost effective basis; the control system comprising a controller means receiving inputs indicative of the outdoor air temperature, the temperature of the outdoor coil, and the operation of the compressor means; the controller means having a timing function which is initiated upon the outdoor coil temperature being at or below a preselected value and the compressor means being operated; the duration of the timing function being determined on a substantially continuous basis as a function of the magnitude of the outdoor air temperature; and the controller means having an operative connection to the system so as to, upon completion of the timing function, place the reverse cycle refrigeration system into an outdoor coil defrost mode of operation.

Abstract: Apparatus to minimize laser angular rate sensor lock in by optimal positioning of the beam path within the laser cavity.

Abstract: A novel mask is used to contour the photodetector body and adhesive layer of a photodetector device on a substrate in which the mask apertures define an angle with the plane of the substrate. Air abrasion at that angle removes unwanted portions of the photodetector body and adhesive layer, leaving a contour desirable for subsequent interconnect metallization.

Abstract: A method of bonding thermoplastic resins to metals. A cylindrical portion of a metal is coated with an uncured adhesive. A quantity of a thermoplastic resin is molded onto the adhesive substantially uniformly about that portion of the metal having adhesive thereon, and a restraining ring is placed about the exterior portion of the thermoplastic resin such that the inner diameter of the restraining ring is substantially equal to the desired exterior diameter of the thermoplastic. The restraining ring is made from nonmetallic material. Induction heating is then performed on the metal for a time sufficient to cure the adhesive.

Abstract: Circuitry associated with a self-contained abnormal condition sensing and alarm annunciating unit for supervising or monitoring leads interconnecting a plurality of such units and for responding to an open circuit condition of such leads so as to actuate an annunciator in a distinctive fashion to signal the open circuit condition.

Abstract: The disclosure describes circuitry for obtaining a compensating voltage signal for a device which is subject to errors caused by changes in a parameter such as ambient temperature. An operational amplifier produces an output voltage at an output thereof indicative of the changes in the parameter. A first and second plurality of series connected resistors are connected between said output and a pair of constant current sources whereby unidirectional electric currents flow through the resistors, junctions being defined between said series connected resistors. Output operational amplifier means are provided, having an inverting input means, a non-inverting input means, and output means at which the compensating voltage is developed. The non-inverting input means is connected to one of the junctions through a series connected resistor and diode, and the inverting input means is connected to another of the junctions through a series connected resistor and diode.

Abstract: A system for sensing seismic and magnetic disturbances, comprising a segmented transducer, such as a line sensor, and electronic circuitry for processing the signals developed by the segmented transducer. The segmented transducer comprises sets of windings wrapped around a ferromagnetic core. Currents are induced in the transducer windings by magnetic field disturbances caused by external ferrous objects. Electronic signal processing circuitry associated with the transducer extracts information from the induced seismic and magnetic signals and activates an alarm if the information meets predetermined criteria. Important criteria used include whether the seismic signals are impulsive, whether the magnetic or stress disturbances are localized, and whether specific thresholds of magnetic and stress activity are reached.