Abstract: The cooling air flow path extends from a blower through a tapered input duct to a large plenum chamber which coaxially surrounds and extends over the top of the deposition apparatus. From this plenum chamber cooling air flows coaxially downward over the surface of the quartz bell jar which forms the reaction chamber, and radially inward through the banks of radiant heater lamps coaxially surrounding the bell jar. Each bank of heater lamps is readily removed for servicing by being rotated into an open position about a pivot axis extending along one verical edge. From the open position, the bank can be slid sideways in slots in the supports and removed from the apparatus.

Abstract: A predominatly hardware-based system for rapidly generating overlay images by painting techniques using a host computer with appropriate graphics-generation operator interface, and for manipulating overlay images with respect to a background image. The system provides for rapid, convenient control of such imaging aspects as color alteration, repositioning the overlays on the background, and predetermining the amount of mask protection to be associated with each image pixel. The system can be readily realized, using available integrated crcuits, in the form of a host-computer plug-in accessory. A bidirectional multiple bus structure serves to interconnect the circuit boards, permitting convenient host-software-controlled configuration of the system.

Abstract: The autoloading mechanism accepts diskettes stacked in an input tray and loads each into a slightly modified commercial disk drive for read-write operations. At the end of these operations, the diskette is either rejected or inserted into an output tray. The diskette transport mechanism uses a pair of belts, unidirectionally travelling along a simple loop-shaped path, to load an input diskette into the drive and insert an output diskette into the output tray while travelling a distance equal to half the belt length. The disk drive is easily removed for servicing or replacement.

Abstract: The hangup apparatus uses an inadvertent off-hook detector circuit designed to detect the off-hook "howler" alert signal transmitted to a telephone by the telephone company when the telephone has been off-hook for a period of time without any user activity. The detector circuit provides an automatic hangup signal to an automatically actuated hangup switch, disconnecting the telephone voice network from the telephone lines and restoring service to the telephone. One version of the invention can be incorporated into newly manufactured telephones, and another is suitable for use with existing telephones. Both versions can be realized using readily available commercial electronic components.

Abstract: An impact detection apparatus (10) includes a device that utilizes multiple sensor elements (11) to determine whether or not a ball lands in or out on a tennis court (12). The sensor positions (13-134) are adjacent to the various boundary lines of the tennis court (12). The sensor elements (11) are layered devices which, when compressed, generate an electrical impulse. The impulse is then analyzed through various signal processing means so that an impact caused a sensor (11) to be compressed may be characterized as being a ball, a footstep, or some other object. In this way, near-simultaneous impacts of a ball and a footstep can be distinguished. If the impact is characterized as a ball that has landed out, a control console (206) will give a visual and/or audible signal so that players, and officials if present, are informed that the ball was out.

Abstract: A write-bias gate in the form of an FET is provided for each of the bit-lines. Each FET has its drain electrode connected to logic 1 and its source electrode connected to the bit-line. When one port is writing, the write-bias gates on the other port(s) are driven by a signal which causes them to enter a pass condition, supplying extra current to pull up the bit lines of the non-writing port(s).

Abstract: A short-focus microwave reflector is located a short distance away from the feed horn and is positioned to reflect the beam of microwave radiation away from the feed axis and toward a large primary reflector antenna for transmission. A conical shield extends from the feed horn to the secondary reflector, joining them together as a unit and preventing sidelobe radiation. The beam of radiation emerges from the shield through an aperture in the sidewall thereof. The short focus of the secondary reflector causes the beam to be focussed approximately at the plane of the aperture, such that the beam diameter is small and the aperture can also be small, reducing stray radiation from the shield structure. Diffraction at the edges of the aperture is reduced by a radially surrounding choke structure which further suppresses sidelobe radiation.

Abstract: A ceramic resonator element having high Q, high dielectric constant, and a low temperature coefficient of resonant frequency is enclosed within a cavity to form a composite microwave resonator having reduced dimensions and weight as compared to a simple cavity resonator. A pair of tuning screws extend into the cavity along orthogonal axes to tune the structure to resonance along these axes at frequencies near the fundamental resonance of the ceramic element. Several such cavities can be formed in a short length of waveguide by the use of transverse partitions at spaced intervals and coupling between cavities can be accomplished by using simple slot, cross or circular irises. In each cavity, a mode-perturbing screw is positioned along an axis 45.degree. from each of the orthogonal tuning screws, such that resonance along either of the orthogonal axes is coupled to excite resonance also along the other.

Abstract: The amplifier device, which may be an FET power amplifier, is of the type having an operating parameter which exhibits thermal instability under constant electrode bias conditions, and thermal stability when bias is varied as a function of ambient temperature in accordance with an empirically determined relationship.The method involves the empirical determination of the varying bias conditions needed to cause thermal stability of the operating parameter over the required range of temperatures, and the provision of a temperature-compensating power supply which produces the necessary bias at each temperature in the range.The temperature-compensating power supply incorporates a bias monitor circuit to produce a control signal which has a nearly constant value so long as bias conditions are in accordance with the empirically determined relationship at every temperature within the range.

Abstract: The antenna system employs a parabolic reflector fed by an offset feed array of circular wave guides located substantially at the focus of the parabolic reflector, but offset from the axis thereof. A plurality of aperture tuning mechanisms disposed at the mouths of the circular waveguides of the waveguide feed array, and having physical lengths much shorter than one wavelength at the frequencies involved, are provided to reduce cross-polarization and mutual coupling between adjacent feeds. The short resonant length of these tuning mechanisms, and their shape which is chosen to generate the TM.sub.11 mode E-field contour line ensures that they are effective over a broad bandwidth of as much as 20% or more. Within this bandwidth, they act as inductive suppressors to control both cross-polarization and mutual coupling between adjacent feeds.

Abstract: A single microwave-reflective antenna "dish" can be used in combination with a plurality of multiple-beam microwave feed arrays to generate or receive multiple-beam-path microwave radiation in several different frequency bands. Each of the feed arrays may operate in a discrete band of frequencies, with the combined radiations of all the arrays illuminating the reflector along a single axis. The optical system is based on the Newtonian model, such that the radiations from several arrays located off the principal axis may be combined by corresponding frequency-sensitive reflective surfaces located on the principal axis. Each of these reflective surfaces serves to direct the radiations from a single feed array toward the reflective antenna, and reciprocally, to direct radiation from the antenna to the associated feed array.

Abstract: The adapter includes a spacer which fits in place of the ball joint at the outer end of the lower control arm. The ball joint is mounted within one end of a sleeve, the other end of which is threaded to fit over the spacer. As a result, the ball joint is secured in a position which is elevated above the lower control arm, causing a lowering of that member and of the vehicle with respect to the wheel and the road surface.

Abstract: A pair of cuffs are positioned on the thigh and calf respectively adjacent the knee joint. Each of these cuffs encloses and is backed by a fluid-filled chamber made of a flexible resilient material. The inner surface of this chamber is bonded to an elasticized fabric band which encircles the leg and positions each of the cuffs immediately adjacent the knee joint.An accordion-folded section of tubing extends from the upper to the lower fluid filled chamber along each side of the knee forming a unitary fluid-filled system. A pair of flexible but inextensible straps overlays each of the accordion-folded tubes and is securely fastened to the cuffs. Upon lateral impact, fluid migrates from the side of the knee which has been struck to the opposite side causing the cuffs to firmly grip the thigh and calf, and the accordion-folded tube on the opposite side to fill with fluid, creating compressive force between the knee joint and the tensioned straps and preventing dislocation of the knee joint.

Abstract: An electrically resistive heater consisting of a helix of resistive wire, the helix being shaped into a toroid or a spiral, with the electrical return lead extending coaxially through the helix so as to provide a magnetic field of equal magnitude and opposite sense to that produced by current in the helix to cancel the magnetic fields.

Abstract: An improved field-effect transistor is provided by forming the conducting channel boundary opposite the gate electrode as a heterojunction. For example a GaAs conducting channel may be bounded by an AlGaAs layer. The conduction electrons can penetrate the boundary very little and are constrained to the channel layer having good transport properties. The output conductance is reduced and the transconductance increased.

Abstract: A light concentrator for use with photovoltaic cells has a novel aspherical shape to provide the desired distribution of energy over the surface of the cell. The cell is usually circular with a current-collecting bus electrode around the circumference of the active surface. To provide for minimum resistive losses due to the current generated in the cell and flowing to the bus, the light may be concentrated in a band just inside the bus with reduced or even zero energy density inside the band. This distribution is obtained by making the ray-deflecting surface of the concentrator as a figure of revolution whose generating line focuses incident rays arriving parallel to the axis of revolution onto a point removed from the axis. Thus, a point source at infinity is "focused" into a circle around the axis instead of the point focus of conventional optics. Solar light is "focused" into an annular ring.

Abstract: By positioning the source and gate electrodes on the opposite faces of the active layer, these electrodes can be brought closer together and may have their adjacent edges mutually aligned or even overlapping. The series source resistance and channel resistance can be greatly reduced, because of this closer spacing, which can not be attained when the electrodes are coplanar. By also locating the drain electrode on the same side of the active layer as the source, the source-to-drain spacing can be significantly reduced, reducing channel length and improving the high frequency performance of the transistor. Further, because the electrodes are located on both sides of the active layer, it is possible to provide a large area contact on the bottom, or substrate, side of the epitaxial wafer structure which can advantageously be used to provide a low thermal and electrical resistance connection for the source contact, for example.

Abstract: A method of improving the thermal emmissivity of a cathode heater wire to allow lower temperature operation of the heater without an attendant lowering in the cathode operating temperature, in which method the surface of a tungsten or molybdenum wire is oxidized, then coated with a salt of a refractory metal, and finally heated to reduce the salt and oxide to their metallic forms thereby causing the heater wire to be roughened and darkened.

Abstract: In a method and apparatus for electrostatically recording on a dielectric coated sheet, a recording head carrying a stylus array is spaced apart from the sheet to form an ionization gap. A charge image is transferred to the sheet by applying an activating voltage between selected styli and a back-up electrode. All styli receive a D.C. bias voltage and selected styli additionally receive "write" pulse voltage. The sum of the bias and write pulse voltages exceeds the threshold breakdown voltage of the gap to ionize the air in the gap under the selected styli. The charge image, created by the ionized air, is subsequently toned to form a visible image. The magnitude of the threshold breakdown voltage is dependent on the length of the gap and the required magnitude of the write pulses depends in part on how accurately the length of the gap is maintained constant.

Abstract: An accelerator for a linear beam of charged particles has a first accelerating section upstream which modulates and accelerates the dc beam. This section is a traveling-wave circuit through which the entire rf power flows from the driving source. Output power from the other end of the traveling-wave section flows through a transmission line to a standing wave accelerating section downstream of the input section. An attenuator and a phase shifter between the two sections allow adjustment in the energy added to the particles in the downstream standing-wave section without disturbing the synchronism of the beam with the upstream accelerating section. As a result a high efficiency of acceleration and narrow energy spread of the final accelerated beam are achieved over a wide range of particle energies.