Abstract: A method of producing fluid organic products from kerogen in situ in a body of oil shale by the application of alternating electric fields having a frequency between 100 kilohertz and 100 megahertz to heat the kerogen in the oil shale to a temperature in the range of 200.degree. C. to 360.degree. C. and to maintain the kerogen in this temperature range for a period of time sufficient to convert a substantial portion of the kerogen in oil shale to fluid organic products which may be collected through fissures produced in the oil shale formation by flowing to a well bore having a collection sump.

Abstract: A microwave cooker digitally programmed in any of a plurality of different cycles whose digital programs are selected from a front panel display. Programs include a cook cycle, a defrost cycle, and/or a defrost and cook cycle, in which a body of refrigerated food to be heated is subjected to microwave energy for a predetermined time in the oven, and then allowed to set for a predetermined time to allow heat produced in the food body by said microwave energy to at least partially disperse throughout the body thereby equalizing the temperature of different food body regions and then applying additional microwave energy for a predetermined time to cook said food body.

Abstract: A fluid valve for a beverage-making appliance such as a coffee brewer, for example, which valve comprises a housing which contains a valve actuating means and which is closed at its inlet end by a filter, the filter being dome-shaped and having a small central aperture whereby air bubbles in a fluid within the valve may escape upwardly and out so that the valve may be used in appliances subject to microwave radiation.

Abstract: A novel anode structure for electron discharge devices, for example, a crossed field oscillator of the magnetron type is fabricated by uniting nonthermally substantially similar cylindrical members each having a boundary wall member and plurality of vane members. The vane member edges are provided with alternate clearance or contacting mating notches to position an annular strap or straps in the complete anode assembly. Less expensive metal castings, such as aluminum, and other suitable vacuum materials, and such techniques as pressure welding and interference fits may be employed without expensive brazing procedures to result in a simplified less expensive anode structure. Different anode vane configurations are simply implemented, such as V-shapes, utilizing castings or similar structures which when joined together form the composite anode assembly.

Abstract: A digitally programmed microwave oven having a microwave generator energized by a high voltage power supply connected to an alternating current source through mechanically actuated oven door interlock switches, with the power supply regulating the current supplied to the microwave generator to compensate for peak voltage variations in the alternating current source by resonating the output of the power supply in the region of the frequency of the alternating current source in which the power supply is initially energized by a semiconductor switch actuated by a computer to accurately control the time of initial supply of power to said power supply at a point which minimizes the input current surge to said resonant circuit by actuating said semiconductor switch at a time substantially .pi./2 radians of said frequency after the zero voltage point of said alternating current source.

Abstract: A compact heating and cooling system in which air ducts are connected to a heat 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: A radar system having automatic compensation to the heater power applied to the final output tube for changes in the peak tube power output. Substantially constant peak power is attained for radar pulses of varying widths and over a plurality of range scales. A controlled voltage is derived in accordance with the peak of the anode power or current coupled to the final transmitter tube. The control voltage is amplified to operate a free-running bistable multivibrator the output of which is transformer coupled to the heater of the output tube.

Abstract: A package heat exchange system using an expanded surface gas-fired burner to supply heat via a heat exchange coil in a dome above the extended surface heat exchanger which heats domestic hot water and supplies heat via the dome to a radiator for heating a living area of a home. A control system provides for utilizing steam from the extended surface heat exchanger to heat the coil in the dome and maintains a first pressure for supplying the domestic hot water and a higher pressure when radiator heat is called for. The heat for domestic hot water may be further heat transferred in a fourth heat exchanger which adjusts the temperature of the domestic hot water. The heat supplied to the radiator may be self-pumping by utilizing steam and the heat to the radiator may be cut off by supplying a control to the return pipe of the radiator which allows the radiator to fill with condensate from the steam.

Abstract: A package heat exchange system using an expanded surface gas-fired burner to supply heat via a heat exchange coil in a dome above the extended surface heat exchanger which heats domestic hot water and supplies heat via the dome to a radiator for heating a living area of a home. A control system provides for utilizing steam from the extended surface heat exchanger to heat the coil in the dome and maintains a first pressure for supplying the domestic hot water and a higher pressure when radiator heat is called for. The heat for domestic hot water may be further heat transferred in a fourth heat exchanger which adjusts the temperature of the domestic hot water. The heat supplied to the radiator may be self-pumping by utilizing steam and the heat to the radiator may be cut off by supplying a control to the return pipe of the radiator which allows the radiator to fill with condensate from the steam.

Abstract: A surface acoustic wave low loss filter device having input and output transducers located along opposed sides of a rectangular propagation path with frequency selective reflective gratings at each of the four corners of the rectangle. Two traveling surface waves traverse the device along opposed paths encountering frequency filtering at the gratings. The two waves arrive at the output transducer additively in phase eliminating the bidirectionality loss normally associated with surface acoustic wave devices. At frequencies for which the gratings are reflective there can be nearly lossless transmission from input to output. At all other frequencies, transmission between input and output transducers is negligible. The device has high sidelobe rejection, adjustable passband skirt slopes, and an adjustable bandwidth.

Abstract: In a switched multipath filter network, the passband is varied by varying the duty cycle of the switches which commutate the constituent filters. When no filter is operative, the output connection of the filters is interrupted to prevent the unfiltered signal passing through, but the network output is smoothed to provide sample and hold action.

Abstract: A reflective grating for a surface acoustic wave device is formed of interleaved sets of contiguous metal strips deposited on the surface of the device. The metal in one set of the strips has a density greater than that of the acoustic propagating medium of the device while the metal of the second set of strips has a density essentially equal to that of the acoustic propagating medium of the device. Typically, a piezoelectric material such as a crystal of quartz or a crystal of lithium niobate is utilized as the base material of the device with the grating being formed of an overlay of alternating strips of gold and aluminum.

Abstract: A package heat exchange system using an expanded surface gas-fired burner to supply heat via a heat exchange coil in a dome above the extended surface heat exchanger which heats domestic hot water and supplies heat via the dome to a radiator for heating a living area of a home. A control system provides for utilizing steam from the extended surface heat exchanger to heat the coil in the dome and maintains a first pressure for supplying the domestic hot water and a higher pressure when radiator heat is called for. The heat for domestic hot water may be further heat transferred in a fourth heat exchanger which adjusts the temperature of the domestic hot water. The heat supplied to the radiator may be self-pumping by utilizing steam and the heat to the radiator may be cut off by supplying a control to the return pipe of the radiator which allows the radiator to fill with condensate from the steam.

Abstract: A microwave oven control system in which the average microwave power may be selected by selecting different duty cycles of a cyclically closing semiconductor switch controlling the AC power supplied to a microwave magnetron anode power supply which has a saturable high voltage transformer with input current surges to said power supply being minimized by turning on said switch in the region a voltage peak of said AC power and with the cycle time of said switch being greater than the AC power cycle time but being substantially less than the thermal response time of a food body being cooked by microwave energy so that changing the duty cycle can change the power applied to the food body rapidly in the event that undesired results such as boiling over or burning of the food body are observed.

Abstract: A performance monitor for use with marine radars which produces a visual indication upon the radar display screen only when the radar transmitter power, and the radar receiver sensitivity and tuning are within predetermined limits. An RF sample of the radar transmitted signal is mixed with a local oscillator signal and the resulting IF signal is coupled to an AFC loop which controls the frequency of the local oscillator. If the amplitude of the radar transmitted signal is above a threshold level, a single frequency response signal of fixed power is generated by the performance monitor and transmitted back to the radar antenna. A distinctive test pattern is produced upon the radar display if the radar receiver tuning is accurate and its sensitivity is sufficiently high.

Abstract: A method is disclosed for dicing individual or groups of diode mesas fabricated upon a single metal heat sink. The undiced device is placed diode mesas down upon a transparent glass plate with the mesas protected in wax. A first mask is positioned upon the opposite side of the plate by alignment with the diode mesas as seen through the plate. Portions of the first mask extend on the plate beyond the edges of the wax and heat sink. A second etching mask is then fabricated upon the bottom of the heat sink by exposing a layer of photoresist through a mask having the same grid pattern as the first mask and which is aligned with the portions of the first mask seen through the glass plate beyond the edge of the heat sink. The diode mesas are etched apart by spraying an appropriate etchant through apertures in the etching mask.

Abstract: A semiconductor device with active junction area determined by the surface of the floor of a hole etched into a body of semiconductor material. A body of highly doped semiconductor material is overlayed with two layers of semiconductor material of the same conductivity type. The layer in contact with the highly doped body is moderately doped while the upper layer is very lightly doped. A hole is etched through the top layer extending slightly into the moderately doped layer. A Schottky barrier contact is plated throughout the etched region. The total parasitic capacitance of such devices is much lower than that of prior art devices and the reverse breakdown characteristics are improved.

Abstract: A microwave oven having a magnetron wave energy supply energized by high voltage pulses at a superaudible frequency wherein the voltage pulses are produced by a decreasing portion of a magnetic flux cycle of said frequency in a transformer added to a voltage on a capacitance whose charge is replenished during a portion of said cycle during which a semiconductor switch connects a winding of the transformer to a source of unidirectional voltage to increase the flux in the transformer thereby energizing the magnetron with voltage pulses from a supply having a substantially constant current characteristic and permitting variation of the constant current level by variation of the average flux density in the transformer.

Abstract: A four frequency laser gyroscope system having a rugged and compact output structure for producing output signals representing the frequency differences between counter-circulating wave pairs circulating as two beams within the gyroscope cavity. A partially transmitting dielectric mirror forms both one of the cavity reflectors and the means for extracting a small portion of each beam. The two extracted beams are combined on a beam splitter. Both the transmitted and reflected beams from the output of the beam splitter, each containing waves of all four frequencies, are utilized. Each resultant beam is then polarization discriminated to extract the desired signal content. The entire structure is adapted for rigid mechanical coupling and may be constructed to have a small size.

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.