Abstract: An adjustable carrier device is disclosed for storage and handling of fragile panel-like structures such as semiconductor wafers, ceramic substrates, LCD panel displays, printed wiring boards and the like. The device is adjustable to receive structures of different sizes without the use of any tools. The device comprises a slotted side wall for receiving one side edge of the panel-like structure, and a sized adjusting member having a semi-circular cross-section which is mounted on an offset pivot for movement toward or away from the slotted side wall to adjust to the size of the product. Slots are formed in the edge of the offset pivot member to receive another edge of the stored structure. A cover is provided for protection to enclose the panel-like structures when placed in the carrier device to prevent damage. No tools are required to adjust the device to different product sizes.

Abstract: Motors (42,44) each have a pinion driving ring gear (62). Motor (42) is mounted on the platform and motor (44) is mounted on ring gear carrier (56). Rotation of either motor rotates carrier (56), hubs (40) and shaft (30).

Abstract: A switched capacitor array (20) for use in a digital-to-analog converter (10), an analog-to-digital converter (60), or other digitally controlled circuit is disclosed. The array includes a plurality of switched capacitors (C(0) through C(15)) of substantially identical value, each having a switched terminal. Logic circuitry (17) responsive to a digital input signal (A) having a value N provides a logic output signal indicative of the digital input signal. Gating circuitry (40) responsive to the logic output signal switches the switched terminal of a selected switched capacitor to an analog signal provided by a digital-to-analog converter stage of lesser weight, and sequentially switches the switched terminals of a predetermined number of the switched capacitors to a predetermined voltage. The selected capacitor and such predetermined number of capacitors are determined by the value N of the digital input signal.

Abstract: Linearity and efficiency of a radio frequency multi-stage power amplification device 10 are increased by employing two tuned circuits 16 and 18 in the driver stage 12 and two tuned circuits 22 and 24 in the high power stage 14. After selecting elements of tuned circuits 22 and 24 in order to optimize the high power stage 14 for efficiency, linearity, and power output, elements are selected for tuned circuits 16 and 18 in order to cause the intermodulation output components associated with the driver state 12 to have a 180.degree. phase angle relative to the intermodulation output components associated with the high power stage 14. This phase angle relationship will cause the intermodulation output component products from the driver 12 and high power stages 14 to cancel.

Abstract: A satellite communications system employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies.

Abstract: An anti-skid braking system control method determines the brake torque on a wheel of a road vehicle to prevent wheel lock-up while retaining braking force. The method utilizes a wheel slip-wheel acceleration phase plane (400), which is divided into at least three and preferably four wedge-shaped sectors (401, 402, 403, 404) meeting at a central point (440), each sector representing one of three available brake control actions (A, H, R) to be taken. The vehicle's wheel slip and wheel acceleration are estimated, a representation of the phase plane is used to determine in which sector the slip/acceleration coordinate lies, and a control command is output to the system for effecting the desired control action in accordance with the sector determined. The control method is adaptive to vehicle speed.

Abstract: Apparatus and method is disclosed for forming an elliptical surface in a mirror 10. The mirror blank is rotated about a given axis and the cutting tool tip 24 is pivoted about an axis C which is generally perpendicular to and spaced from the workpiece axis 16. As the cutting tip 24 moves in an arcuate path about point C the instantaneous radius R between the cutting tip and the C axis is adjusted by way of a linkage 34 which translates movement generated by a cam surface 36 and follower arm 32 into horizontal movement of the tool cutting tip 24.

Abstract: A solar cell assembly wherein a solar cell is provided with electrical layer contacts for both the p-type semiconductor layer and the n-type semiconductor layer which are exposed on a top side of the solar cell, so that electrical contact to both layers can be made from the top side of the cell, and a glass cover overlying the solar cell includes a pair of U-shaped electrical cell contacts extending over the sides of the glass cover so that one leg of each U makes contact with one of the layer contacts and the other leg is accessible from the top of the cover glass. External electrical contact to the cell is easily and conveniently made, and cells can be electrically joined to adjacent cells in an array using a connector bar. The glass cover also supports the solar cell so that excess material on the substrate of the solar cell can be etched away to reduce the weight of the solar cell assembly.

Abstract: Rear and forward reflector shells or dishes (36,38) are independently supported on a dynamically rigid truss structure (12) by means of separate studs extending from the forward nodes of the truss to the two shells. Forward node (22) carries adjustable rear shell stud (52) and independently carries adjustable forward shell stud (80). Both of the studs have flat portions oriented normal to the radius of the shell so that radial shell expansion due to temperature and temperature differential minimize shell distortion.

Abstract: A rate controllable damping mechanism is disclosed. The mechanism includes a chamber disposed within a housing; an element mounted for movement within the chamber; a damping material, preferably a low melting temperature metal alloy, in the chamber for preventing the movement of the element at a first temperature and for damping the movement of the element at a second temperature; and a heater for selectively increasing the temperature of the damping material from the first temperature to the second temperature. Controlled damping is effectuated by heating the fluid material until it reaches a molten state at which the resultant fluid damps the movement of the element in a conventional manner. A novel method is also disclosed for structural stress relief.

Abstract: A honeycomb facesheet material, and honeycomb made therewith, wherein the facesheet includes a layer of graphite paper bonded to a layer of graphite cloth, woven from widely spaced graphite fibers. The facesheet is impregnated with an epoxy resin during manufacture, and the facesheet is bonded to an open end of the honeycomb under elevated pressure and temperature to effect curing of the epoxy resin. The graphite paper supports the layer of graphite cloth during handling to prevent misalignment of the fibers, and also effects a widely distributed bond between the fibers and the underlying honeycomb.

Abstract: A satellite communications system employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies.

Abstract: A high efficiency envelope amplifier is disclosed. The invention includes a power supply, a comparator and several switches. The power supply is capable of providing multiple outputs. The comparator measures the amplitude of an input signal against one of several threshold levels. When the input signal is within a predetermined range, a selected power supply output is switched incrementally switches small amounts of power, switching losses are substantially mitigated.

Abstract: An axial electrostatic ion thruster for use on a dual-spin stabilized spacecraft is disclosed. The thruster is mounted on the spun portion of the spacecraft and continuously fired for an integral number of spin periods to provide north-south velocity and attitude control. To achieve zero attitude precession with a statically imbalanced despun platform, or an intentional attitude precession generally, the ion thrust is spin-synchronously varied between two non-zero levels to achieve a prescribed Fourier component amplitude and phase at the spin frequency. Modulation of the thrust is achieved with constant ion beam current by complementary modulation of the beam voltage, V.sub.B, and accel voltage, V.sub.A by varying the ion extraction system grid voltages. This varies the thrust while maintaining a constant total accelerating voltage V.sub.TOT =V.sub.B +.vertline.V.sub.A .vertline..

Abstract: A satellite communications system employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies.

Abstract: An equal power amplifier system (100) for amplifying a plurality of signals for transmission by an active phase array antenna (20), and a compact plural level beam-forming network (98) for forming a plurality of such signals, for example on excitation patterns for frequency scanned virtual beams, are disclosed. The amplifier system uses at most only a few sizes of power amplifiers (130, 134) to amplify efficiently numerous signals having significantly different amplitudes. This is accomplished by distributing the task of amplifying signal pairs (A.sub.i, B.sub.i) composed of one large amplitude signal and one small amplitude signal to an equal power amplifying apparatus (130; 230), which includes two hybrid couplers (236, 238) and two equally sized power amplifiers (232, 234). The first hybrid coupler (236) divides the two signals (A.sub.i, B.sub.i) for input into the two power amplifiers.

Abstract: Two reflecting surfaces (102, 104) pass through each other at an intersection line (450) lying in a plane of symmetry (106). The two surfaces share a common aperture (101) and the surface contours of the two surfaces are preferably mirror images of each other and are arranged such that the respective two foci (110, 120) of the two surfaces are equidistant (108) from the center of the shared aperture and offset from each other in equal and opposite directions (109a, 109b) from the plane of symmetry.

Abstract: A satellite communications system employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies.

Abstract: A wideband frequency selective surface 10 is disclosed which includes a square grid 12 having a first plurality of parallel conductive lines perpendicularly intersecting a second plurality of parallel conductive lines to provide a plurality of squares. The distance between the parallel conductive lines is p. A plurality of conductive square loops 20-23 are included within the plurality of squares. The distance between each line segment of each square loop and the corresponding adjacent parallel conductive line segment of the square grid is g. The distance g is greater than one quarter times the distance p for wideband performance.

Abstract: An iris is located in a common wall separating two microwave enclosures such as waveguides and cavities for coupling electromagnetic power between the two enclosures. The iris is formed of an aperture elongated in one direction to define a longitudinal axis of the aperture with opposed first and second sides parallel to the axis. Portions of the common wall at peripheral regions of the aperture are extended from the first and second sides towards the iris and perpendicularly thereto to form teeth, there being an array of teeth extending from the first side and an array of teeth extending from the second side. The teeth are readily polarized as magnetic dipoles by surface currents induced in the wall by electromagnetic waves for increased coefficient of coupling of electromagnetic field components through the iris.