Abstract: Disclosed is a millimeter wave bulk effect RF power limiter consisting of a lanar PIN diode formed on a gallium arsenide (GaAs) substrate which also comprises the waveguide structure for RF energy in the 60-300 GHz range. The PIN diode is comprised of a wedge of intrinsic type semiconductor material formed across the top surface of the substrate and having mutually opposing regions of p and n type semiconductor material fabricated in the side edges of the wedge to which is attached planar beam leads. With suitable electrical operating potentials applied to the PIN diode avalanche breakdown occurs at a critical RF power level which acts to limit the flow of RF energy flow in the structure past the location of the PIN diode. Such a structure permits the device to be integrated into the front end sections of receivers utilized in communications, missile guidance and radar systems operable in the millimeter and sub-millimeter frequency range.

Abstract: An acceleration resistant crystal features two crystals mounted together h at least two axes of each crystal being in antiparallel relationship with respect to corresponding axes of the other crystals. The two crystals can be chiral pairs and thus have three corresponding axes in antiparallel relationship for acceleration resistance in any arbitrary direction with respect to the crystal axes.

Abstract: Polymer bonded nitramine based explosives and propellants are prepared by diation polymerization of a polymer precurser, such as methyl methacrylate, in mixture with a particulate nitramine, e.g. RDX, wherein the nitramine particles are coated with an effective amount of a liquid polyhydric alcohol for overcoming the action of the nitramine to inhibit or retard such radiation polymerization.

Abstract: A gas comparison probe contains first and second sensor elements isolated om each other. Air is drawn across a surface to be monitored and directed onto the first sensor element. Air is drawn from a location spaced away from the surface to be monitored and directed onto the second sensor element. A flow constrictor in the air flow path to one of the sensor elements is used to calibrate the outputs of the two sensor elements under known conditions before attempting to monitor air flow which may contain a gas to be detected.

Abstract: An improved device for the air dropping of platform-mounted cargo is presed wherein a multi-staged parachute system allows for a rapid descent during the initial phase of the trajectory and then reduces the rate of descent during the terminal stage to allow for a safe landing.

Abstract: Apparatus and method for using one laser range finder to calibrate another imilar range finder. The range finder under test receives a simulated return pulse from the transmitter of the second range finder. An external trigger initiates the transmitter of the range finder under test and a short time later initiates the transmitter of the second range finder. The transmitted beam of the second range finder is directed into the receiver of the range finder under test and it halts the range readout thereof. This range readout is compared to the reading on an external timer arranged to measure the time interval between the emission of the transmitted beams of the two range finders.

Abstract: A ceramic substrate is metallized by a method including the steps of:(A) chemically cleaning the substrate,(B) sputter etching the chemically cleaned substrate,(C) sputtering a chromium layer of about 200 angstroms in thickness onto substrate,(D) sputtering a molybdenum layer of about 3500 angstroms in thickness onto the chromium layer,(E) sputtering a copper layer of about 25,000 angstroms in thickness onto the molybdenum layer,(F) firing the coated substrate in dry hydrogen at about 1000.degree. C. for about 10 minutes,(G) plating a copper-silver brazing alloy of about 0.0003 inch in thickness onto the copper layer, and(H) firing in dry hydrogen at about 700.degree. C. for about 10 minutes.

Abstract: Mechanical interference between a cast explosive material and a casing prnts rotation of the cast explosive material during machining thereof and improves symmetry and performance of the shaped-charge warhead. The cast explosive material may be keyed to the casing by flowing portions of the explosive material into a plurality of cavities in the casing before curing. Alternatively, pins may extend inward from the casing into the explosive material which surrounds them when cast and resists relative motion therebetween when cured. Alternatively, the explosive material may be pre-cast into an appropriate shape, cured and pressed into the casing. Protuberances to fit into holes in the casing or indentations to fit over pins extending into the casing may be formed on the pre-cast explosive. Engagement between the protuberances or indentations and the holes or pins respectively is attained when the explosive material is pressed into the casing.

Abstract: A normally-open two stage float valve for use with a suction tube leading om a vehicle fuel tank. As the fuel tank begins to run dry it is desired that the float valve close off the tank to the suction force. The valve of this invention includes a float-operated pilot valve element that equalizes forces on the opposite faces of the main valve element as the float moves through its actuation stroke. A lifting head is associated with the pilot valve element for mechanically lifting or lowering the main valve element relative to the main seat when the forces have been equalized.

Abstract: A timing system for providing a fuze function time for firing a fuze which s independent of power source rise time. A non-volatile counter is programmed with a count indictative of the function time, and is read out starting at missile take-off to fire the fuze upon completion of read out of the count. Inhibit circuitry is provided for automatically reducing the stored count during the setting operation and for subsequently inhibiting the reading out of the counter by a time corresponding to the reduction in the stored count. This time is selected to be greater than the largest expectable rise time of the fluidic generator power source, but no longer than is necessary.

Abstract: The millimeter and submillimeter wavelength oscillator includes a Gunn diode coupled to a hole in a ferrite image waveguide in such a way that a portion of the waveguide acts as a resonant cavity, and oscillation results. A coil surrounding the portion of the waveguide has a variable dc current applied to it to variably magnetize the waveguide and hence correspondingly vary the oscillator frequency. By applying an RF signal to the Gunn diode, the oscillator frequency can be mixed with the RF to yield heterodyne or intermediate frequencies.

Abstract: A dielectric waveguide power limiter for a self-oscillating mixer operating n millimeter-wave frequencies. The limiter includes a high resistivity silicon dielectric waveguide and a Gunn oscillator. A plurality of dielectric resonators each including a high uniaxial anisotropy ferrite sphere embedded therein are positioned between the power input end of the waveguide and the Gunn oscillator.

Abstract: The delivery of alternating current from a source to a load, especially a sistance heater, is accurately controlled as a function of temperature through the employment of a bidirectional solid state switch. A full-wave power control for the solid state switch includes a temperature probe comprising one or a combination of voltage and temperature sensitive devices.

Abstract: A unique shape is mathematically prescribed for a "lens" which refracts cimated light passing through it in such a way that any linear scale modulating the incident light is distorted into a logarithmic scale at the final image plane.

Abstract: A precision power gear train assembly particularly adaptable for use with vehicles having a 360.degree. rotatable turret mounted thereon. The assembly embodies novel spring and stop means to minimize backlash and to limit gear tooth disengagement of the enmeshed output pinion and ring gears of such an assembly. More specifically a pinion-ring gear assembly mounts a gear box to oscillate about an axis parallel to the pinion axis of rotation such that the tooth pressure between pinion and ring gear biases the teeth apart, increasing backlash. A preloaded spring biases the gear teeth into tight mesh to eliminate backlash until the tooth pressure force exceeds a predetermined maximum. Thereafter, further increases in the tooth pressure force separates the teeth by compression of the spring beyond its preloaded compression. A stop limits tooth separation.

Abstract: A bump stop for a trunnion-mounted weapon that includes a torsion bar shock bsorber carried by the receiver portion of the weapon for absorbing shock loads as the weapon nears the limits of its upward and downward motion. The bump stop is advantageously characterized by compactness, high energy-absorbing capacity, durability, insensitivity to temperature or other environmental variations, and usability in two directions, up and down.

Abstract: Small arms projectile wherein lead core thereof has its front or nose portion replaced with a structurally integral low-density plastic filler material, the filler material shearing from the lead core to provide a double wound tract upon slight penetration of the projectile into a soft target.

Abstract: A pulsed laser beam intensity monitor measures the peak power within a selectable cross section of a test laser beam and measures integrated energy of the beam during the pulse period of a test laser. A continuous wave laser and a pulsed ruby laser are coaxially arranged for simultaneously transmitting optical output energy through a crystal flat during the time a test laser pulse is transmitted through the flat. Due to stress birefringence in the crystal, the ruby laser pulse transmitted through the flat is recorded and analyzed to provide peak power information about the test laser output pulse, and the continuous wave laser output reflected from the crystal flat provides a measurement of energy during the test laser pulse.

Abstract: The invention relates to a firing mechanism for high acceleration applicans having a body member having a first chamber, a second chamber and a web member separating the first chamber from the second chamber. A first spring is positioned within the first chamber and a second spring is positioned with the second chamber. A firing pin is positioned substantially in the first chamber and has a spring retaining section at its forward end and a release cam mechanism at its rearward end. An arming pin is positioned substantially in the second chamber and has a spring retaining section at its rearward end and a release cam mechanism at its forward end. The release cam mechanism of said arming pin is dimensioned to interlock with said release cam mechanism of the firing pin with the two release cam mechanism and is positioned within the web member and is restrained against release by the web member.

Abstract: 1,5-Methylene-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DPT) is prepared by eacting nitrourea with formaldehyde in aqueous solution in the presence of sufficient added water soluble base, such as sodium hydroxide, to initiate evolution of carbon dioxide gas and formation of an intermediate compound, and reacting the intermediate compound with aqueous ammonia and formaldehyde to form DPT.