Abstract: A transverse excitation atmospheric pressure laser employing a preionizing flash board formed on one of the sides of the laser tube. The side wall of the laser tube acts as an insulating support plate having a backing plate on the outside surface and a set of subsidiary electrodes on the inside surface. The subsidiary electrodes are short cylinders bonded to the inside surface of the support plate and having a flanged portion at the opposite end. The preionizing discharge takes place between adjacent subsidiary electrodes in the region between the flanged portions and is thus removed from the support plate. The material for the flanged portions has a high melting point and a low sputtering capability.A U-shaped enclosure provides a grounded housing for all the high voltage components and also provides a path for the discharge currents.

Abstract: A probe detects sonic energy in liquids and in materials containing liquids such as the flesh of living beings, the probe being particularly adapted for medical ultrasonics. The probe is constructed of materials having acoustic impedances substantially equal to that of water to maximize the transfer of sonic energy in a living being to an electric signal within the probe for accurate detection of high frequency pulses having a duration less than a microsecond. A piezoelectric polymer serves as the transducer and is mounted at the end of the probe housing between a thin metallic window which serves as one electrode, and a metallized rubber rod which serves as the second electrode and sonically insulates the transducer from the housing. An acoustically absorbent ring affixed to the perimeter of the face of the probe, and a flaring of the back end of the probe, reduce the diffraction and reflection of acoustic waves for improved accuracy in the measurement of submicrosecond pulses.

Abstract: The process and apparatus for extracting the products of kerogen in situ from an oil shale body by supplying energy selectively to the kerogen by high frequency electric fields in the frequency range between 100 kilohertz and 1000 megahertz at an intensity which heats the kerogen to a temperature range between 250.degree. C. and 500.degree. C. to allow pyrolysis of the kerogen prior to substantial heat transfer to the surrounding mineral portions of the oil shale.

Abstract: A compact heating and cooling system in which air ducts are connected to a host exchanger system through which a coolant fluid from a condensing unit or a heating fluid from a compact water heater is selectively directed by a control circuit so that the system may be mounted outside a building to be heated and/or cooled.

Abstract: An imaging system, particularly useful for acoustic medical diagnosis of a human subject, utilizes an array of radiating elements or sonic transducers located side-by-side and positioned along the subject. Signals received by the transducer are applied to a pair of pattern generation circuits which weight the individual signals by factors of +1, -1 or 0. Graphs of the weighting factors as a function of transducer location have the likeness of cosinusoidal and sinusoidal Fresnel patterns, these patterns being produced by the two circuits. Upon reception of signals, the weighted signals of each pattern are summed together, multiplied by cosinusoidal and sinusoidal reference signals and then summed together to provide a radiation pattern which converges from the array to a focal point in front of the array while eliminating a diverging pattern from a virtual focus behind the array.

Abstract: An electromagnetic wave ring resonator is disclosed including means to spatially rotate the electromagnetic field distribution of waves resonant therein about the direction of propagation of such waves to enable such waves to resonate with opposite senses of circular polarization, and means, including a laser amplifier medium, to provide different indices of refraction to resonant waves of the same sense of circular polarization as they pass through such laser amplifier medium in different directions. With such arrangement the two mentioned means enable the waves to resonate with four different frequencies. In a laser gyroscope using such ring resonator the electromagnetic field distribution rotating means includes a catoptric arrangement which, together with the last-mentioned means, reduces the loss, scatter and linear birefringence associated with the ring resonator included in such gyroscope.

Abstract: A microwave tube having a heated cathode with a rare earth magnet positioned inside the evacuated envelope of the tube and at least partially shielded from thermal radiation from the cathode and/or anode so that the magnet may be operated at elevated temperatures while protected from environment such as oxygen in the air to prevent degradation of the magnetic properties of the magnet at temperatures up to 500.degree. C. during processing of the tube or up to 250.degree. C. during operation of the tube with thermal shielding from the hot cathode preventing any surface of the magnet from exceeding such temperatures.

Abstract: A deflection amplifier gain correction circuit for a beam penetration color cathode ray tube having a split high voltage anode in which the deflection waveform is shaped as a non-linear function of the final anode voltage and as a function of a dynamic focus waveform used for the electrostatic focussing system in the cathode ray tube. The shape of the correcting waveform is adjusted by adjusting the amounts of the dynamic focus waveform and the anode switching voltage waveform which are multiplied to produce a resulting waveform which varies as a function of deflection position and anode voltage and is summed with a waveform which is a non-linear function of anode voltage. Such a system can be adjusted for each individual display unit to compensate for production variations in a color penetration tube using two different colored phosphors.

Abstract: A modulation system for use in generating a multiphase carrier for digital communication systems which avoids phase and amplitude errors due to temperature and voltage variations inherent in balanced mixers, when used as phase modulators. In this invention, resistive divider networks are used to generate the output vector array. Each output vector thus, has an independent resistive adjustment which has no effect on the other vectors to provide individual and separately aligned phase vectors which are selected for transmission by an addressable multiplexer to provide a phase modulated carrier representing multiplex input data.

Abstract: An amplifier having a gain control terminal amplifies an input signal to produce an output signal of a desired magnitude. A gain control circuit coupled between the input and output signals and to the control terminal includes detectors of the input and output signal amplitudes. The control circuit further includes a first impedance network connected to the control terminal and a feedback circuit connected in series therewith, the feedback circuit including a second impedance network complementary to the first impedance network. A feedback signal of the feedback circuit is multiplied by the amplitude of the input signal and combined with the amplitude of the output signal and a reference signal at a summing point of the feedback circuit to maintain a response time of the control circuit which is essentially invariant with respect to the amplitude of the input signal.

Abstract: A system for electronically producing and displaying target position history trails in a PPI radar. Digital target positions within a selected sector zone from all targets meeting predetermined amplitude and duration criteria are stored in a memory for single azimuth scans at predetermined intervals. The data from the scans are interleaved and read out of the memory for display with the real time PPI targets. When the memory is filled, the oldest plots from each target are dropped to make room for new plots.

Abstract: An underwater mapping system in which a swath of terrain, much wider than a sonar beam width, is observed by means of a sonar beam scanned in the cross track plane of a ship. Filtering and correlation techniques are employed to compensate for distortions in echoes emanating from the ocean bottom by a selection of filter coefficients in accordance with the orientation of the sonar beams and by providing a simulated echo envelope for correlation.

Abstract: A heat exchanger for efficiently transferring heat from a first fluid body to a second fluid body within a selected container, tank or reservoir, comprising an elongated tubular hoselike plastic body of deformable material wrapped around the container and filled with the first heated fluid, the plastic body being deformable under the pressure of the first fluid so as to conform to the exterior surface of the container whereby more efficient transfer of heat between the fluids is achieved.

Abstract: Apparatus for fracturing and/or heating subsurface formations wherein an alternating current electric field is produced in the frequency range between 100 kilohertz and 100 megahertz between electrodes spaced apart in the formation and a radio frequency generator supplying a voltage between said lines with suitable loading structures tuned to the frequency of the generator to resonate the electrodes as a parallel wire transmission line which is terminated in an open circuit and produces a standing wave having a voltage concentration at the end of the line.

Abstract: A safety interlock system is disclosed for microwave ovens or other high voltage electrical apparatus incorporating sensor means for detecting any malfunction. Means are provided for interrupting line input power or actuating a failure indicating device or a combination of both. Thermally actuated means, such as bimetallic or meltable elements, as well as circuit breakers, relays and fuses are described. The sensor means are associated with each of the interlocks and do not carry regular equipment load current until such time as a malfunction of the companion interlock occurs. Replacement of the faulty equipment by authorized personnel and manual resetting of the interrupt or indicating means before the oven is energized again reduce the risk of accidental radiation, electrical shock or damage to the apparatus. .Iadd.