Abstract: Frequency agility may be added to fire control radars by replacing the conventional receiver-protector/stationary-filter combination located between the duplexing circulator and the receiver input with a passive high power ferrite limiter and YIG tracking filter combination.

Abstract: A receiver for detecting a double side-band noise like signal, in which the receiver is swept over a defined RF spectrum of interest, a phase inversion of the double side band signal is provided and multiplied with the received double side-band noise-like signal to produce an IF signal, and correlation circuitry is provided to produce an output whereby the presence of the double side-band noise like signal is detected, and controls the stopping of the sweep at said detection.

Abstract: An acoustic delay line is used in a feed-back loop in the traveling wave tube repeater chain of an electronic countermeasures system to provide a wider transmitted pulse (than the pulse received by the ECM system) resulting in range gate deception in an opposing tracking radar.

Abstract: A nonvolatile memory cell is disclosed that has a buried n+ layer from which charge (electrons) is injected into the insulator of n-channel MNOS (Metal Nitride Oxide Semiconductor) type devices.

Abstract: By adding an indicator control panel to the cockpit and a small receiver-decoder unit between the transponder and the antenna of aircraft having a conventional air traffic control radar beacon system transponder, mid-air collision avoidance capability is obtained. The BACAS (Beacon Add-on Subsystem for Collision Avoidance System) receiver-decoder unit in an aircraft interrogates the associated ATC (Air Traffic Control) transponder to obtain and store the ATCRBS Mode C reply altitude information. The 1090 MHz transponder Mode C reply is given 5 MHz on-off amplitude modulation by the receiver-decoder unit and is radiated into space through the ATC antenna. Identical BASCAS hardware in aircraft within range sense the specially-modulated (5 MHz), Mode C reply and immediately act to trigger their respective ATC transponders into emitting Mode C replies with essentially the same special modulation characteristics except for a different modulation frequency (10 MHz).

Abstract: A ferrimagnetic sphere that is biased to the subsidiary resonance mode and placed within a microwave slotted resonant structure functions as a frequency selective microwave power limiter. When the power level of a signal at the input port exceeds a threshold level, the device prevents the power level at the output port from increasing further. A weak signal present simultaneously passes with relatively little attenuation if it is slightly offset in frequency.

Abstract: The novel structure disclosed comprises an n-type epitaxial layer on a p.sup.- type substrate with p.sup.+ type top gates diffused into the epi-layer and p.sup.+ buried gates aligned with the source side of the top gates. The top-gate diffusion extends far into the drain region.

Abstract: A magnetic bubble domain structure and method of making comprising a film of a nickel-iron alloy of 80 to 83.5% nickel content and substantially zero constant of magnetostriction formed by vapor deposition of the alloy onto a flat substrate at a substrate temperature in the range of room temperature to 200.degree. C. at an angle of incidence of approximately 60.degree. to a film thickness of 0.2.mu.m to 3.0.mu.m, the film being immersed in a magnetic field perpendicular to the film and of 1600 to 2400 oersteds intensity.

Abstract: A graphic curve digitizer is disclosed wherein the x-y coordinate values of a response curve (made electrically conductive) are obtained by a digitally controlled x-y conductive probe and electronic system sensing when the probe contacts the curve by the voltage signal existing in the conductive curve due to the antenna effect of the conductive curve in an environmental alternating current electromagnetic field.

Abstract: In a porous electrode primary battery a sensing grid is positioned in a cell on or near the surface of the porous cathode facing the separator and anode. The voltage measured between this sensing grid and the conventional cathode current collector grid is a function of the current distribution within the electrode which is continuously changing as the battery discharges, thus the measured voltage is indicative of the state of charge of the particular cell having the sensing grid and for a battery containing cooperatively connected cells, the state of the battery in general.

Abstract: The liquid nitrogen level in a flask is controlled by the degree of immersion of two sensing coils of copper wire in the liquid nitrogen activating a solid state switching circuit which controls a liquid nitrogen inlet flow valve. Manual override and sensor fault indication is provided.

Abstract: In a porous electrode primary battery a sensing grid is positioned in a cell on or near the surface of the porous cathode facing the separator and anode. The voltage measured between this sensing grid and the conventional cathode current collector grid is a function of the current distribution within the electrode which is continuously changing as the battery discharges, thus the measured voltage is indicative of the state of charge of the particular cell having the sensing grid and for a battery containing cooperatively connected cells, the state of the battery in general.

Abstract: A single digitally programmable divide by "N" counter controls a timing sequence composed of a plurality of timed intervals. Each interval in the sequence is independent of the other intervals even though the same programmable divide by N counter is used to control the length of each interval. The completely digital controller automatically reprograms itself in a predetermined manner for each interval in a sequence. A single clock circuit provides the interval lengths typically ranging from milliseconds to hundreds of hours for the controlled intervals. The output from the controller is a repetitive series of "1"s and "0"s of the adjustable timed durations.

Abstract: In a solid state, folded cavity, laser having a fundamental frequency and a second harmonic frequency, the efficiency of the laser is improved by placing a quarter wave plate, at the lower frequency, in the leg of the cavity containing the lasing element and positioning the quarter wave plate by angular rotation to compensate for any polarization discrimination to the laser rod gain.

Abstract: Two inversely ganged variable capacitors having a common movable element varying the capacities such that when one capacitor is at maximum capacitance, the other is at minimum capacitance, have, after initially charging, a substantially constant contained or trapped charge distributed between the two capacitors. As the capacities of the capacitors are varied, a potential difference is developed between the fixed plate of one capacitor and the fixed plate of the other. When these two potential points are connected to a load, charge is transferred from one capacitor to the other as a current flow through the load. The total charge is not diminished, the energy supplied the load being the energy expanded on moving the movable charged plates. As the movable plates are moved in a cyclic manner an alternating current is provided to the load.

Abstract: An unstable resonator is disclosed that couples power out of an annular gain region in a single transverse mode through the use of spherical mirrors. A four-element cavity comprising a confocal unstable resonator with a double-sided 45.degree. output coupling mirror in conjunction with a flat feedback mirror is used. A flat, totally reflecting feedback mirror is placed on the normally plane wave output side of the confocal cavity, forming an annular mode between the feedback mirror and the coupling mirror. A plane annular wave is fed back into the resonator, which alternately converges and diverges to produce an output beam in the form of a diverging annular beam. The converging wave unstable cavity has the novel property whereby increasing geometric magnification corresponds to increasing saturation of the active medium, in contrast to a conventional edge-coupled unstable cavity.

Abstract: An improved gallium arsenide solar cell is provided by ion implanting both the top and bottom of a plural vertical PN junction eutectic gallium arsenide cell body to obtain an electrical drift field, with multiple ion implants progressively larger in dose and progressively lower in implant energies to provide a P-type ion implanted top layer having a common connection to all P regions of the cell body and an N-type ion implanted bottom layer having a common connection to all N regions of the cell body. The implanted regions of the cell are pulsed electron beam annealed at room temperature.

Abstract: An incoming longwave infrared beam sharing the same aperture with an outgoing high power laser beam is separated from the laser beam path by a combination of a dichroic mirror and a diffraction grating.

Abstract: A polycrystalline rod of silicon is refined by repeatedly passing it through a zone melt condition, then a dopant impurity is ion implanted in the polycrystalline rod and a seed crystal is attached. A final zone melt pass is then made converting the rod to single crystal structure and distributing the dopant.

Abstract: A nonvolatile Charge Injection Device (NOVCID) of Metal-Nitride-Oxide-Semiconductor (MNOS) material is operated in a novel manner in combination with a flip-flop to provide a charge pumped volatile memory storage system that can be continuously nondestructively read and on command, by applying a high positive potential to the field plate of the NOVCID, the information stored in the volatile mode is transferred to the nonvolatile state. To recover the stored information an alternating current signal is applied to the field plate.