Abstract: An uncomplicated and reliable temperature sensor has a pair thermistors coupled in parallel with a current source that is connected in series with a load resistor. Temperature variations cause a robust current output change that generates a corresponding robust output voltage determined by a proper selection of the load resistor. Increased sensitivity is provided by the robust current to avoid many of the problems otherwise associated with D.C. amplifiers (e.g., drift).

Abstract: An injector assembly is provided for use with a high heat, high pressure bustion chamber which utilizes a highly corrosive fuel. The injector assembly includes a ceramic injector which has an annular ceramic flange. A metallic retaining apparatus is provided which includes a pair of retainer plates and a tightening device. In a preferred embodiment one of the retainer plates is a retainer ring. With this arrangement the ceramic flange is clamped between the retainer ring and the retainer plate by the tightening device. The retainer ring is provided with an annular groove. An annular spring is disposed within the groove in engagement with the ceramic flange. Because of the different coefficients of expansion the metal of the retaining apparatus will expand away from the ceramic flange when the combustion chamber is operated. When this occurs the annular spring will expand to maintain a high integrity seal between the injector assembly and the combustion chamber.

Abstract: An integrated circuit memory element is capable of storing analog information. The memory value can be increased and decreased incrementally with no knowledge of the current state and may be stored for a long period of time. Analog memory information is stored as an electrical charge on a floating gate structure and modification of this information is accomplished by the use of hot-carrier injection to transport electrons off of as well as onto the floating gate (to erase as well as to program electrically).

Abstract: A device is provided for processing an echo received by an array of N receiving elements from a target at range R ensonified by an LFM signal of bandwidth B transmitted for a duration T. The device receives each elements output f.sub.n (t) over the elements total receiving time and selects time window element outputs f'.sub.n (t), which are discrete portions of f.sub.n (t), each time window extending from an arbitrary initial time T.sub.0 to time T.sub.f and is spaced from T.sub.0 no more than T and, if there is a target within the window, an echo is received at time T.sub.n. Further the device produces element frequency difference outputs g.sub.n (t) from the frequency difference between a replica of at least a portion of the transmitted LFM signal and the time window element outputs f'.sub.n (t), the outputs g.sub.n (t) being tones with frequencies directly proportional to the time T.sub.n of the target from the time T.sub.0 so that the target range R=(c/2)(T.sub.0 +T.sub.n)+.DELTA.R.sub.

Abstract: An adjustable spanner wrench and combination tool for use by firefighters provided. An elongate handle has first and second ends between which a variety of firefighter's tools are defined. A first jaw portion is affixed on one end thereof to one end of the handle. The first jaw portion extends from the one end thereof as a pair of spaced apart generally parallel side walls. A first end of a second jaw portion is movably fitted between the parallel side walls of the first jaw portion. The second jaw portion is further provided with an elongate slot having a plurality of slot projections extending therefrom A hinge pin is affixed between the parallel side walls of the first jaw portion and passes through the elongate slot of the second jaw portion. In this way, the second jaw portion may be selectively positioned by allowing the hinge pin to come to rest in one of the plurality of slot projections. Also, the second jaw portion is free to rotate about the hinge pin through an angle of approximately 270.degree..

Abstract: A method for fabricating a self-aligned, gate diffused junction field eff transistor is provided which includes the steps of forming an n-type layer on an indium phosphide, semi-insulating substrate; forming spaced apart source/drain metal contacts on the n-type layer; forming a metal gate on the n-type layer between the spaced apart source/drain contacts, where the metal gate is insulated from the source/drain contacts and includes a metallic p-type dopant material; and forming a p-type region in the n-type layer beneath the metal gate so that the gate contact and the p-type region have coincident boundaries with respect to each other at the surface of the n-type layer. The method may also be employed to manufacture a bipolar transistor by allowing the self-aligned and diffused p-type region to extend through the n-type layer to the semi-insulating substrate.

Abstract: A laser having a Cr.sup.3+ doped Colquiriite mineral host gain element, such as Cr:LiCAF, Cr:LiSAF or Cr:LiSGAF, is pumped by the pumping beam from at least one visible laser diode to provide tunable laser emission. TheSTATEMENT OF GOVERNMENT INTERESTThe invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Abstract: An internally folded scalable laser has a gain medium with an internal face nd an external face and at least one internal-fold face subtending an angle which may be about 90.degree.. An output coupler that is partially reflective of the resonator mode is oriented to receive and reflect resonator mode in a direction normal to the internal face to avoid resonator mode astigmatism and to define a folded hemispherically-shaped resonator cavity extending from the output coupler and through an active volume in the gain medium to the external face. A pumping mode source disposed adjacent to the external face is oriented to focus a first pumping mode in a direction normal to the external face in a boom waist at or inside the external face in the folded resonator cavity to define an active volume in the gain medium and to avoid pumping mode astigmatism.

Abstract: A novel bridge type optoelectronic (OE) sample and hold circuit based upon current steering demonstrates a clear superiority in performance with respect to a direct OE sample and hold circuit. The bridge type OE sample and hold circuit permits a high-speed signal to be sampled with high accuracy to offer high charging capability, commanding signal isolation, reduced time jitter and reduced holding charge leakage which are distinct advantages over conventional electronic sample and hold circuits.

Abstract: A method for fabricating a conformal optical waveguide on a semiconductor bstrate which results in an improved conformal processing method of producing ferroelectic ceramic waveguides that is integratable with conventional electronic and optoelectronic devices. First, a patterning of a desired waveguide configuration is made on a desired semiconductor substrate. A conformal confinement layer is fabricated in the pattern of the desired waveguide configuration on the semiconductor substrate. The conformal confinement layer has an index of refraction. Next, the method calls for a placing of a sol-gel waveguide precursor in the conformal confinement layer. Next the spin casting of a sol-gel waveguide precursor shapes a sol-gel conformal waveguide layer in the conformal confinement layer on the semiconductor substrate.

Abstract: Mechanically cooperating assemblies on an undersea vehicle and an instrumation target assure the making of a rigid coupling for passing electrical, optical or fluid information between the vehicle and the instrumentation and reduce the complexity of such a coupling from a three-dimensional to a two-dimensional maneuver by the vehicle. An undersea vehicle locates a pair of spaced-apart vertical cables which are attached to an instrumentation target assembly and engages them anywhere along their length with a converging grabber assembly mounted on the forward moving underwater vehicle. After engaging the cables, the grabber assembly merely slides along the cables toward the instrumentation target assembly.

Abstract: A system which overcomes the effects of acoustical torpedo counter-measures y using an attack on a countermeasure as a logical step toward the attack on a "real" target. A slight bearing error is introduced into a torpedo homing system to cause the torpedo to miss a small "decoy" target while permitting a "real" target to be hit. After attacking and missing the "decoy", the system then redirects the torpedo towards the "real" target.

Abstract: A differential amplifier for gigahertz bandwidth electrical signals using fiber optics and integrated optical devices has a differential gain which is a function of the electrical to optical and optical to electrical conversion factors. The common mode rejection ratio of the differential amplifier at 1 GHz was greater than 30 dB and the common mode rejection ratio depended on the time difference between the differential amplifier inputs. A differential amplifier fabricated in accordance with this inventive concept could be used as an integrated module in radar and communications systems.

Abstract: A very low frequency and low frequency transmitting antenna parameter monring system is used to measure the electric circuit parameters in near real time of very low frequency and low frequency transmitting antenna systems transmitting frequency shift keyed modulation. The primary parameters measured by the system are the antenna feed-point voltage, antenna current, gross resistance, gross reactance and steady-state phase angle between the voltage and current. Four primary sections provide for antenna system sensing by sensors, triggering, analog-to-digital conversion of the sensor outputs and computer processing of the digital data to arrive at the desired antenna parameters. These parameters are essential in evaluating antenna performance and in diagnosing problems with the antenna system.

Abstract: A method for fabricating graded heterojunction electronic devices uses laser melting and recrystallization of layered films to create an epitaxial alloy heterojunction. Layering an appropriately doped polysilicon film over a germanium film that has been deposited upon a base region allows the laser melting and recrystallization thereof to create a graded epitaxial silicon/germanium alloy heterojunction. Other film materials could be selected for other graded heterojunctions. The method provides for sufficient device design flexibility including deeper junction formation and reduces the problems associated with contamination.

Abstract: A moving target simulator is provided for testing a wide variety of radars ithout the need for a direct connection between the simulator and the radar under test. The simulator accurately replicates the pulse width and amplitude of transmitted radar signals and provides a delay feature that permits simulated target scenarios to be presented to a radar under test. The simulator incorporates control features that allow Doppler frequency changes to be accounted for and that permit signal level changes to be made as in accordance with inverse 4th law distance-dependent target-return power variation.

Abstract: The present invention provides a method for measuring the intragranular and ntergranular critical current of a granular superconductive material, comprising the steps of: 1) conducting a substantially rectangular electronic pulse through the material so as to conduct a current through the material such that when the intergranular critical current of the material is exceeded, any grains present in the material remain in a superconducting state when the current level is below the intragranular critical current; 2) measuring the current through the material while conducting the pulse; 3) measuring a voltage difference across the material while conducting the pulse; 4) determining the intergranular critical current through the material by discerning a non-zero voltage difference across the material and contemporaneously measuring the current; and 5) determining the intragranular critical current through the material by varying the current to discern a current level at which the electrical resistance of the materi

Abstract: A system is provided for generating a blue-green optical signal with a wavelength in the range of 450-550 nm and corresponding to a Fraunhofer line, comprising: a plurality of laser diodes, each laser diode generating a first optical signal having a first wavelength, .lambda.; a plurality of optical fiber, each optical fiber having a first end optically coupled to receive the optical signal from one of the laser diodes and a second end for emitting a second optical signal having a second wavelength, .lambda./2, where the wavelength .lambda./2 corresponds to a Fraunhofer line, the second ends forming a fiber optic bundle for emitting a composite optical signal comprised of each of the second optical signals; a servo-controlled gimbal for supporting the fiber bundle to direct the direction of the composite optical signal; and a computer operably coupled to provide direction control signals to the servo-controlled gimbal.

Abstract: The ground-wire detector of the invention is a portable device used to locate buried ground-wires of an energized very low frequency/low frequency antenna system operating within the frequency range of 15 kHz to 200 kHz. This ground-wire detector has an oscillator section that is tunable by a dial located on the detector. Because of this feature, an operator can change the oscillator's frequency without the need for component replacement.The detector of the invention includes two series-connected oppositely-wound coplaner coils spaced approximately 15 inches apart. The coils are oppositely wound to generate a maximum detection signal when centered over an energized ground-wire. The coils generate a detection signal when placed within the vertical magnetic fields formed by energized antenna ground-wires and are designed to incur minimal interference from the large horizontal magnetic field radiating from an adjacent transmitting antenna station.

Abstract: The detection and localization of an antiship torpedo is accomplished by ustic and optical means. A ship's sonar determines the approximate location of the incoming torpedo and a laser scans this location with energy in the blue-green spectrum. Surface reflections are gated out of a linear detector array and reflected portions of the scanning beam which penetrate the water's surface are divided among the elements of the linear detector array into field of view element signals. These field of view element signals are subsequently compared in time and amplitude to determined disparities between them which point to the torpedo's position, depth and bearing. Optionally, spectral and polarizing filters are provided to enhance the signal to noise ratios and to facilitate signal processing.