Abstract: A power combiner using a circularly cylindrical cavity, dimensioned to support the TM.sub.020 mode, to combine the power from coaxial diode oscillators is shown to comprise: (a) a first plurality of such oscillators disposed about the periphery of such cavity; (b) a second plurality of such oscillators disposed in coincidence with the first spatial null in the electric field in such cavity; and (c) a plurality, similar in number to the second plurality of such oscillators, of electrically conductive bridges interposed between the top and bottom walls of the cavity in-between the center conductors of the coaxial diode oscillators in the second plurlaity of such oscillators.

Abstract: A solid state transmitter/receiver operating at 94 GHz is shown to comprise an injection-locked pulsed oscillator for transmitting interrogating pulses and a first local oscillator for heterodyning with received signals to produce an intermediate frequency (I.F.) signal, both such oscillators being phase-locked to a master oscillator operating at a frequency below 94 GHz.

Abstract: A motor control system for a rotating anode type of X-ray tube comprising an axially rotatable rotor provided with a radially extended target disc, an electrically wound stator encircling a portion of the rotor, and a motor controller electrically connected to the stator. The motor controller includes circuitry for initially energizing the stator a predetermined interval of time to accelerate rotation of the rotor, and then periodically energizing and de-energizing the stator at a frequency to utilize the inertia of the rotor and the target disc in maintaining the rotation of the rotor when the stator is deenergized.

Abstract: A high power factor AC to DC power supply having a high frequency pulse producing circuit comprising an inductor supplied with rectified raw AC power through a semiconductor switch which provides dynamic power factor correction by maintaining the width of the on-times of the switch substantially constant throughout each cycle of the input AC power. The peak energy stored in the inductor during the on-times are a function of the amplitude of the instantaneous voltage of said rectified AC power, so that each time the switch is turned off, the output pulse of current supplied to the load by the inductor has a time duration which is a direct function of the instantaneous voltage value of the rectified AC power. The output load has a filter whose time constant is greater than a cycle of said rectified AC power, and the average on-time of said switch is varied over a number of cycles of said AC power to regulate the output voltage of said supply.

Abstract: Bodies of a ferrimagnetic material are disposed within small cavities provided in a magnetometer. The magnetometer is initially calibrated utilizing an electromagnet to produce an applied magnetic field of either known field strength, H.sub.DC, or known field distribution. Radio frequency energy is fed equally to each cavity and each material and results in resonance frequency output signals which may be coupled to a visual display. When the calibrating magnetic field is of known uniform strength, H.sub.DC, the orientation of the bodies is changed until each of the resonance signals have a frequency substantially given by f.sub.c =.gamma.H.sub.DC where .gamma.=2.8 MHz/oersted. When the calibrating magnetic field has a known field distribution the orientation of bodies is changed until such resonance signals have frequencies related to one another in accordance with the relative magnetic field strengths passing through the cavities.

Abstract: A sonobuoy depth selector utilizes the tension in the attaching cable between the suspended sonobuoy and the supporting float to select the length of the attaching cable. Bobbins are attached to the cable at predetermined distances from the float. The bobbins are also mounted on a solenoid actuated pin which is tapered to cause only the bobbin resisting the tension in the cable to slide along the pin to a release position near the end of the pin. Momentary electrical energization of the solenoid causes the pin to release only the bobbin under cable tension thereby allowing the cable to pay out from a cable reel until stopped by the bobbin attached to the next larger predetermined length of cable.

Abstract: A transistor switching circuit is provided for providing an indication of when the level of an input signal has passed through a first threshold level, such indication continuing unless such input signal has returned beyond the first threshold level to a second threshold level. Such circuit is useful in indicating whether the battery of a battery powered device should be replaced taking into consideration small variations in the output of the battery after the initial replacement indication has been provided.

Abstract: A fiber optic connector assembly comprising a tubular coupling device having an end portion disposed for encircling an end portion of a fiber optic cable, and a slidable apertured spacer axially disposed within the coupling device. The spacer has a central aperture disposed for alignment with a polished end surface of a filamentary light conductor in the cable, and has an annular surface encircling the aperture for abutting an end surface of an opaque sheath encircling the light conductor.

Abstract: A miniature rate-integrating gyroscope is shown to comprise: an electrical motor (whose rotor, when rotating, constitutes a gyroscopic mass) mounted in a single degree of motion gimbal within a cylindrical case; a motion sensor to determine any rotation of such gimbal with respect to such case, such sensor including a transformer having a primary winding and a secondary winding movable with respect to each other so that the phase difference between alternating signals in the primary and secondary windings is analogous to such rotation; phase detecting circuitry to produce a control signal representative of such phase difference; a torque generator responsive to the control signal to null any rotation of such gimbal; and a fluid damper to critically damp any rotation of such gimbal.

Abstract: Antenna for use with food product in a microwave oven, where one or more antennas are positioned into the food product for efficient and distributed heating of food product. The antenna includes a coaxial assembly of an inner conductor and an outer conductor with dielectric therebetween. A load end, configured as a probe, positions into the food product. A source end antenna element structure delivers power to the load end and subsequently to the food product. The structure at the source end may include a probe center conductor as well as gain antenna structures. The outer conductor may likewise be configured including ground plane disc, a folded-over coaxial outer conductor or the like.

Abstract: An absolute magnitude circuit is provided wherein an input signal is fed to one input of a differential amplifier circuit, the output of such amplifier circuit being coupled to a second input thereof through a negative feedback loop, such feedback loop having two output terminals with an inverter coupled therebetween; and a switching circuit, responsive to the polarity of the input signal, for coupling a selective one of the pair of output terminals to an output of the absolute magnitude circuit, with the voltage at the output of the absolute value circuit having the same polarity independent of the polarity of the input signal.With such arrangement, since the input circuitry to the operational amplifier is independent of the polarity of the input signal, the gain and biasing of the absolute magnitude circuitry is independent of input signal polarity.

Abstract: A phase shifter includes three cascade interconnected phase shift stages. Each stage includes a quadrature coupler and a pair of field effect transistors (FET), having a pair of gates, a drain, and a source, connected in a common (grounded) source configuration. The drain of each FET is coupled to an input port of the quadrature coupler to provide two signal paths having an electrical pathlength difference corresponding to a 90.degree. differential phase shift. In the third stage, a length of transmission line is coupled between a drain of one of the FET's and one input port of the coupler to provide a signal path having an electrical pathlength corresponding to a 180.degree. phase shift. An input signal is fed to one of the gates of each FET of the first stage, and voltage level control signals are fed to the second one of gates of each FET of the first stage, to control the amplitude of the signal coupled to each drain.

Abstract: Lumped passive components including a capacitor having a silicon nitride dielectric, a tantalum film resistor, and a capacitor having a tantalum oxide dielectric are formed on a semi-insulating substrate by first providing an insulating layer, here of silicon nitride, over the substrate and metal contacts having previously been formed on such substrate. The metal contacts provide a first plate for each one of such capacitors. A tantalum layer is reactively sputtered on the insulating layer, and a protective masking layer is next provided on such tantalum layer. An area where the anodized tantalum capacitor is to be formed is then opened in the protective masking layer over a selected one of the metal contacts. A portion of the tantalum is anodized in such area to form an area of a tantalum oxide (Ta.sub.2 O.sub.5). The area where the tantalum oxide is formed is confined generally to the area in the tantalum layer over the contact.

Abstract: A gas surface range having modular burner cartridges and a down draft ventilation system. The cartridges can be removed for repairing, cleaning, or changing the range top configuration. For example, one cartridge type may include tubular burners and an igniter mounted in a pan so that a grill may be positioned thereover to form a grilling surface. A second cartridge type may include conventional top surface burners and an igniter mounted in a pan. Each range compartment into which the cartridges insert have two orifice hoods and an electrical connector rigidly secured therein. The positioning of an inserted cartridge is such that the mixer heads of the burners align with the respective orifice hoods and a rigid conductor of the igniter makes electrical contact with the connector. The connector also has a second terminal for providing an electrical return for the igniter. One type of cartridge also includes an extending post which permits it to only be inserted in one particular compartment.

Abstract: Apparatus and method for curing sheet rubber by radiation of microwave energy. The sheet rubber is wrapped around a metal cylinder forming a roll with a layer or liner of microwave transparent material separating the adjacent rubber layers. The ends of the roll are shielded from microwave energy by metal disks which support the cylinder. The disks sit between rollers of a roller conveyor which is activated to provide the result of rotating the roll for uniform heating in a microwave field.

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. A plurality of groups of spaced radiators produce the electric fields for heating the kerogen. A dipole radiator in the subsurface formation is supplied with electromagnetic energy through a transmission line from an energy generator on the surface.

Abstract: A radio frequency network is provided having a plurality of field effect transistor cells, each one of such cells having a reactive element, and coupling means for electrically interconnecting the plurality of field effect transistor cells, such coupling means having an impedance in accordance with the reactance of the reactive elements of the cells to provide such radio frequency network with a predetermined characteristic impedance related to the impedance of an input circuit which feeds radio frequency energy to an input one of the plurality of cells. With such arrangement the coupling means and the plurality of field effect transistor cells provide the radio frequency network with a predetermined characteristic impedance which is related to the impedance of the input circuit.

Abstract: A microwave cooking container comprising a conductive layer to which is bonded a layer of material having high hysteresis loss at microwave frequencies. When subjected to microwave radiation the hysteresis loss material heats to its Curie point where its loss is substantially reduced while the dielectric loss is minimized by being effectively shielded by its proximity to the surface of the conductive layer. The conductive layer may be a metal dish cover whose outer surface supports a plastic bonded ferrite and whose inner surface contacts a food body in a metal dish. The Curie point region of the ferrite is lower than the degradation temperature of the plastic. Overlapping the walls of the dish and cover forms a microwave seal to prevent microwave heating of the dish contents.

Abstract: A gimbal assembly for a monopulse antenna gyroscopically stabilized on a moving vehicle is shown to comprise a tripartite bearing having a fixed spherical inner section, an annular central section, connected through a helical spring to the moving vehicle, mounted on the spherical inner section and an annular outermost section rotatably mounted on the central section to form a gyroscopic mass that may be precessed.