Abstract: A magnetic circuit including a structure for magnetically cladding a permnt magnet solenoid to eliminate flux leakage therefrom. The cladding includes hemispherical magnetic cladding elements located at the ends of the solenoid in order to eliminate sharp end corners and thus further suppress flux leakage from the magnetic circuit.

Abstract: A radiochromic dosimeter for use as a tactical or like dosimeter for measuring absorbed ionizing, radiation dose of relatively high range. This dosimeter includes an outer barrel, a first ultraviolet light opaque, ionizing radiation transparent tube, a liquid solution of leuko dye disposed in the first tube, a second ultraviolet light opaque, ionizing radiation transparent tube, a liquid solvent disposed in the second tube, the tubes having end sealing beads, the outer barrel having end tube supports, a filter disposed next to output ends of the tubes, a lens disposed next to the filter for viewing filtered light circles, and a light adjuster for controlling light amount passing into the second tube input end.

Abstract: An ambient condition sensor is embodied in an oscillator which generates an output signal having a frequency which is proportional to the ambient condition of the environment in which it is located. The oscillator includes a ring resonator consisting of a metallic ring located in the output plane of a grounded source gallium arsenide MESFET type transistor oscillator formed on a temperature sensitive dielectric substrate. The circumference of the ring is directly related to the ring resonator's resonant frequency. More particularly, the circumference of the ring is a multiple of the wavelength of the oscillator's output signal. Such a device permits unmanned, remote and inexpensive temperature sensing in places generally unsuited for operator presence.

Abstract: An optical fiber is formed by continuously coating a precursor core filam with a glass-forming coating. The precursor filament is continuously moved from a storage reel through a stationary coating station. The filament is then moved through a stationary glass-forming station and is continuously processed to convert the coating to a glass, with the core either removed from the fiber during glass forming or becoming an integral part of the ultimate fiber during glass forming. The glass fiber is then moved continuously through a glass densification station and is densified in a continuous process. The fiber is thereafter provided with a protective coating as it moves through a stationary coating station and the completed optical fiber is continuously reeled.

Abstract: The area of a loop made of superconducting material is decreased to incre the magnetic field on the surface of a test piece adjacent the loop for determining the critical field, H.sub.c, of the test piece. A loop with a gap having a temporary plug placed therein in which a persistent current is established has a nozzle forming the gap thereon for receiving a test piece. The test piece then completes the circuit permitting removal of the temporary plug. The area of the loop is then decreased resulting in an increase in magnetic field at the surface of the test piece. When the critical field of the test piece is reached, magnetic flux will leak from the internal area of the loop, thereby determining the critical field of the test piece. A continuous length of superconducting material can be tested for discontinuities or spots of low critical field, H.sub.c.

Abstract: A cylindrical superconducting solenoid adapted to receive cylindrical inserts within the bore thereof. The inserts are selected having a permeability or radial thickness which will absorb or conduct a portion of the magnetic field within the interior bore of the cylindrical solenoid. Thereby, the interior magnetic field can be adjusted to any predetermined value without changing the total amount of trapped flux within the superconducting solenoid.

Abstract: Periodic permanent magnet (PPM) stacks for use in wigglers and traveling e tubes having magnetic cladding. A variable magnetic potential cladding along the adjacent surfaces of working magnets is used, thereby increasing the efficient use of magnetic material and increasing the magnetic field while minimizing weight. The magnetic cladding has a direction of polarity perpendicular to the direction of polarity of the working magnets. Extraneous magnetic fields are also reduced. A magnetic shunt, or soft iron, is used to facilitate the conduction of magnetic flux and create an equal magnetic potential exterior surface.

Abstract: A first shell of magnetic material having a hollow cavity is magnetized and as a remanence to produce a first uniform field in the cavity. The first shell has a temperature coefficient such that the first uniform field varies with temperature in a first direction. A second shell, mounted concentrically with the first shell, has a remanence substantially the same as the remanence of the first shell and is magnetized to produce a second uniform field in the cavity in the same direction as the first uniform field. The second shell has a temperature coefficient that is opposite to and much larger than the temperature coefficient of the first shell. Changes in temperature will cause the cavity fields produced by each of the two shells to vary in opposite directions such that there will be virtually no net change in the combined cavity field.

Abstract: A tunable bandpass filter comprises a flat ferrite body having first and ond spaced, coextensive microstrip conductive lines on its upper surface. A winding encircles the ferrite and conductive lines so that a variable d-c current in the winding varies the magnetic permeability of the ferrite and thus the center frequency of the filter.

Abstract: A cladded magnet twister device for a microwave/millimeter wave source is comprised of a plurality of polygonal similarly magnetized magnet segments. Each magnet segment is displaced radially in equal angular segments along the central axis relative to its neighboring segment to provide a transverse helical field and is comprised of a relatively short length of an array of bar magnets, cladding magnets, bucking magnets, pole pieces and corner pieces. The pole pieces are secured to the ends of the bar magnets and have convex faces which are directed inwardly toward one another.

Abstract: A GaAs MESFET coupled to an interdigited photoconductive detector uses the nternal gain of the interdigited photoconductive conductor and the transconductance of the MESFET to convert an optical control signal to an electrical current control signal which in turn is used to control a GaAs MMIC.

Abstract: An improved permanent magnet solenoid having a stepped transition in axial agnetic field profile and comprised of two permanent magnet solenoids, with appropriate cladding, placed in tandem and a radially magnetized ring magnet placed within the working cavity of the solenoids at the joint of entire structure.

Abstract: A test fixture for inverted microcircuits having spaced shelf assemblies h parallel shelves for respectively supporting a substrate for a microcircuit and a substrate for a ground plane in such a manner that the distance between them can be varied while test signals are coupled to the microcircuit via a coaxial cable coupled to a fitting on one shelf assembly and signals are coupled from the microcircuit via a coaxial cable coupled to a fitting on the other shelf assembly to test apparatus for determining the performance of the circuit.

Abstract: A magnetic dipole of varying magnitude and orientation is disclosed wherein he dipole is comprised of an outer magnetic shell and an inner magnetic sphere which is rotatably mounted within the outer magnetic shell. Both the outer shell and the inner sphere are mode of magnetically rigid material and are each magnetized in a uniform direction parallel to a single longitudinal axis. The inner sphere is preferably rotated within the outer shell via a non-magnetic means such as a rod.

Abstract: A resonant microwave isolator is described in which a diagonal slot is fod in the top conductor of a microstrip, a strip of ferromagnetic material is mounted over at least a portion of the slot and magnetic flux is established in the ferromagnetic material in a direction intersecting the slot.

Abstract: A plurality of acoustic charge transport (ACT) tapped delay lines are coupled to respective antenna elements of a phased array antenna assembly to control the beam steering of either a transmitted or received electromagnetic wave in the megahertz (MHz) range. Each delay line, moreover, is comprised of an ACT channel region which operates as a delay line and further includes multiple signal output taps which can be selectively addressed from an address bus coupled to a digital controller for providing a predetermined delay. With each delay line being individually controlled, an improved technique for beam steering is provided.

Abstract: The invention disclosed herein is a battery cell compartment which is use in limiting the number of batteries in any battery cell matrix. The battery cell compartment permits the use of relatively few batteries for practically any power need. The battery cell compartment essentially comprises a housing for a plurality of battery cells; a door panel; a series of concentric springs attached to the door panel and positioned such that when the door panel is secured to the housing the concentric springs are aligned with battery cell berths in the housing; circuit power pins electrically connected to the concentric springs; a diode, a thermal fuse and a current fuse placed in series with the circuit power pins.

Abstract: A narrow, high energy, electron beam is caused to impinge upon an integra circuit. The accelerating voltage of the electron beam is increased until the electrons have just enough energy to penetrate through the thickness of the passivation layer of the integrated circuit. The accelerating voltage is then increased a predetermined amount (3-5 KeV) above the voltage required for passivation layer penetration. The transmitted electrons interact with the sublayer of thin film material and generate distinct X-rays. The increased-intensity electron beam is x/y or raster scanned over the area of interest of the integrated circuit. The X-ray intensities generated during the raster scan are detected and stored. After a complete scan of the area of interest, the X-ray intensities are read, processed through a formula that compensates for absorption effects, and visually displayed.

Abstract: A device is disclosed which uses permanent magnets to manipulate charged ticle beams, such as those employed in traveling wave tubes, wigglers, and undulators. Tapered pole pieces are inserted between magnets in a periodic permanent magnet array, and the taper is oriented away from the beam path. The magnets themselves may also be tapered, but the taper is oriented toward the beam path. Tapering is described according to the cross sections formed when the plane which contains the beam path intersects the magnets and pole pieces.

Abstract: An array of fiber optic RF filters each responsive to a predetermined wavngth forms a channelizer for a wide bandwidth receiver used in a dense signal environment having complex modulations. Each fiber optic RF filter comprises a resonant cavity formed from a section of multimode optic fiber with a dielectric mirror deposited at each end and wherein the cavity length corresponds to one half the respective modulation signal wavelength of optical energy fed into the filter optic cavity from a laser diode which is modulated by the received RF energy.