Abstract: An arrangement is shown to process mainlobe echo signals and range sidelobe signals in the receiver of a pulse compression radar by first converting such signals to a set of digital numbers and then correlating, number by number, such set with a set of reference numbers describing the mainlobe echo signals and the negative of selected range sidelobe signals.

Abstract: A tilt-angle electron gun provides a conical beam of electrons for injection into an axially aligned magnetic field of a gyrotron tube. The beam is formed by an electrostatic lens system for focussing and accelerating the electrons within a magnetically shielded region. The conical beam is substantially monoenergetic and laminar so that after injection into the magnetic field the resulting hollow beam has gyrating electrons which have an axial velocity spread sufficiently low for high efficiency gyrotron amplification.

Abstract: An integrated circuit memory is provided wherein an array of memory elements is addressed by a decoder circuit responding to an address signal. The decoder circuit includes a plurality of sections, each one thereof being used to address a different section of the array. A decoder section selector is provided which, in response to the addressing signal, determines the section of the array being addressed and electrically couples the one of the plurality of decoder circuit sections which is coupled to such addressed array section to a power source while electrically decoupling the remaining section of the decoder circuit from such power source. With such arrangement, only a portion of the decoder circuit is electrically coupled to the power source when addressing the array thereby reducing the power consumption of the integrated circuit memory.

Abstract: A method of operating a Doppler radar to track a target when main beam clutter is present is shown to comprise the steps of: (a) forming, from all signals exceeding a predetermined amplitude that are received by the pulse Doppler radar during a predetermined period, a range/Doppler matrix having NXM cells, where N is the number of range bins and M is the number of Doppler bins, with a digital one in any cell representative of a return signal with a given Doppler shift frequency from a reflector at a given range; (b) sequentially reading, in accordance with a predetermined program, the contents of the cells in the range/Doppler matrix to form digital numbers with digits indicative of the presence or absence of a reflector in adjacent cells; (c) comparing each digital number to a digital number representative of a target return signal; and (d) generating a frequency control signal when the comparison step indicates a target return signal to adjust a local oscillator in the pulse Doppler radar to effect tracking

Abstract: A digital frequency synthesizer is provided for producing a signal having a predetermined frequency. Such system includes: a computer for calculating the residue of the frequency to be synthesized modulo a predetermined frequency, f.sub.LO, and the nearest modulus frequency; an intermediate frequency generator for generating an intermediate frequency signal having a frequency equal to the determined residue; a harmonic generator section for combining the intermediate frequency signal with a plurality of harmonics of the predetermined frequency, f.sub.LO, to produce a composite signal having a plurality of frequency components separated one from another by the predetermined frequency, f.sub.

Abstract: A refrigerator having a crisper pan with a back passageway that is always open and a front passageway that is adjustable so that the operator can adjust the amount of flow through ventilation to control the humidity in the pan. The lid for the pan also functions as a refrigerator shelf and the back passageway is defined by a gap between the lid and the back of the pan. The front passageway is defined by a front lid plenum having a floor with a plurality of ports. A slide gate positioned in the plenum has a plurality of windows which, by sliding laterally in the plenum, can be made to respectively align with the ports to enable flow through ventilation. Full or partial sealing of the ports is provided by sliding the slide gate laterally to alter the alignment of the windows with the ports.

Abstract: An improvement in a microwave oscillator using a GaAs FET as the active element is shown to include a phase detector responsive to a portion of the positive feedback signals applied to a resonator having a high Q and to a portion of the signals out of the GaAs FET, shifted by 90.degree., to obtain signals to degenerate noise internally formed in the GaAs FET.

Abstract: A radar antenna is shown in a first embodiment to have a ground plane and a feed line on opposite sides of a dielectric sheet and a ring-shaped antenna element on another dielectric sheet to form a microstrip assembly wherein such antenna element is capacitively coupled to the feed line. In a second embodiment the radar antenna has a parasitic antenna element on still another dielectric sheet, such parasitic antenna element being in register with the ring-shaped antenna element.

Abstract: A four-frequency laser gyroscope system having improved accuracy is constructed using a single solid block of low thermal coefficient of expansion material. A four-segment nonplanar propagation path provides a first frequency splitting. A second splitting is provided by a Faraday rotator having a thin slab of rare earth-doped glass positioned within an aperture in a permanent magnet. A narrow angle of incidence is provided for the beams of incident upon the output mirror to prevent cross coupling between beams within the output optics structure. Blocking the gaseous flow path reduces output frequency drift caused by contaminating particles.

Abstract: A raster display apparatus for converting radar input data which is formatted to produce a Plan Position Indicator (PPI) presentation on a cursive display to a format which achieves a PPI type image on a raster display. The apparatus generates radar images on a raster display screen which appear as targets having continuous arcs of the proper length around the placement position of a radar. Average video levels within successive discrete fixed azimuthal standard angle increments are stored in a radial buffer memory for various increments of range. These video levels are used for all points within the presently active standard angular increment. Radial distance of a given image is computed for changes in orthogonal components such as X or Y using simple prestored sine and cosine functions. Conversion calculations comprise primarily additions using adders.

Abstract: A microwave oven having a low friction bearing support for a rotatable microwave feed assembly which includes a primary radiating antenna axially coupled to a cylindrical metal stub that vertically extends from the microwave cavity through an aperture into the waveguide where it is excited by microwave energy. The stub has a bottom cylindrical bore which inserts over a microwave transparent post that extends upwardly through the aperture from a horizontal cross bar suspended by two legs connected to the cavity ceiling. The cross bar may be oblique to the waveguide to centrally and positively align the post in the aperture. The roof of the bore has a downward spherical surface which provides a low friction bearing with the microwave post. The feed assembly also includes a microwave transparent turbine against which a stream of air is directed to rotate the feed assembly.

Abstract: A distributed power amplifier includes a plurality of field effect transistors (FETS), each one of such FETS having gate, drain and source electrodes, such FETS having cascaded gate electrodes and cascaded drain electrodes successively coupled between an input terminal and an output terminal. The gate electrode of each one of the successively coupled FETS is coupled to the input terminal through a corresponding one of a plurality of capacitors, and a common bias source through one of a corresponding plurality of high impedance bias paths. Since the gate electrodes of each FET are coupled to the input terminal through a capacitor, the coupling capacitor in combination with the inherent capacitance of each FET provides a potential divider into each gate electrode. Therefore, the power fed to each gate electrode is selected by selecting the value of capacitance for the coupling capacitors.

Abstract: A fairing segment for a cable is of composite construction which combines an elastomeric fairing body with a flexible spring-steel clip in the fairing nose. The elastomeric body allows the fairing nose to conform to the cable catenary in the flow stream, presents a smooth leading edge of the flow, and reduces drag. The clip is flexible in the direction of the plane of the fairing to conform to bending of the cable over sheaves or in the water. The spring steel clip allows the fairing to freely rotate about the cable and to align with the flow stream by maintaining low interfacial friction between the cable and the fairing. The clip also minimizes or prevents cold flow of the elastomeric nose portion of the fairing segment into the interstices of the cable armor. The tail portion of the elastomeric body is stiffened to prevent cupping or bending which would cause kiting of the cable.

Abstract: A magnetically tuned resonant circuit for selectively coupling radio frequency (r.f.) energy between an input coupling circuit and an output coupling circuit through a resonant body disposed between such coupling circuits. Each coupling circuit includes a plurality of spaced conductors which are arranged to selectively spatially distribute r.f. energy fed thereto in order to provide, in the region where the resonant body is disposed, a magnetic field having a predetermined spatial distribution. Such magnetic field distribution is selected in accordance with characteristics of the resonant body to reduce coupling of unwanted spurious r.f. energy through the magnetically tuned resonant circuit.Further, a ground plane conductor associated with such coupling circuits has a selected portion thereof removed to provide a void therein, and a portion of the resonant body is disposed within the void provided in the ground plane. The size of the void is selected to increase coupling of r.f.

Abstract: A refrigerator having a reversible cold air meat keeper for providing convenient access thereto regardless of the side of the refrigerator that the doors are hinged. The cold air is channeled into a plenum behind the back wall of the refrigerator compartment and there are at least two spaced ports communicating from the plenum into the chamber. The cold air meat keeper has a conduit extending from the rear wall thereof. In one predetermined mounting position of the meat keeper, the conduit removably couples with one of the ports for receiving cold air from the plenum. In the alternate predetermined mounting position of the meat keeper, the conduit removably couples with the other port for receiving cold air.

Abstract: Apparatus for storing a periodic signal and for recycling complete cycle portions of such stored periodic signal is provided, such apparatus comprising: means for converting an input sinusoidal signal into a corresponding first train of pulses; means for producing a second train of pulses representative of samples of the input sinusoidal signal; means for producing a signal related to the difference in time between the leading edge of the first train of pulses and the leading edge of the second train of pulses to provide a control signal related to a time interval between a first time such time difference is less than a predetermined value and a second later time such time difference is less than such predetermined value; storage means; and means, responsive to the control signals for recycling complete cycles of the first train of pulses through the storage means.

Abstract: A top loading clothes washer adapted for installation under a fixed or stationary upper structure such as a stacked dryer or countertop wherein the washer is pivotable to a forward tilt-out position providing access to its top. The bottom front of the washer is truncated and the pivot axis which is defined by a stable base is behind the truncation and in front of the center of gravity of the washer. A latch is provided to lock the washer in its upright washing position. The latch is releasable by an operator actuated control provided the water level in the tub is below a predetermined level. Accordingly, forward tilting of a full tub is prevented. Also, the operator actuable control energizes a mechanism which assists in the forward tilting of the washer thereby reducing the pull force required of the operator. More specifically, a biased hinge creates a backward torsion on the washer to provide increased stability during a spin cycle and the mechanism functions to counteract the torsion.

Abstract: An arrangement for determining the rotational position of the rotor of an electrical gyroscope is shown to include:(a) at least one sensor including a Hall effect crystal having a rotating magnetic field applied thereto, such field being synchronous with the field causing rotation of the rotor;(b) a phase-lock loop, responsive to square wave signals corresponding to signals out of the Hall effect crystal and a voltage-controlled oscillator to provide a signal approximating the rotational position of the rotor; and(c) a phase detector, responsive to negative going transitions of the square wave and to reference pulses to synchronize the rotational position of the rotor with the reference pulses.

Abstract: A plurality of microwave semiconductor devices is provided by plating a thin heat sink layer on a surface of a wafer of semiconductor material, masking selected portions of the heat sink layer, and plating unmasked portions of the heat sink layer to form a support layer. Substantial portions of the semiconductor material are removed to form a plurality of mesa shaped diodes, at least one semiconductor mesa shaped diode being formed in each region of the semiconductor material disposed on the masked portions of the heat sink layer. Thus each mesa shaped diode, or sets of mesa shaped diodes, has formed on one surface thereof a thin heat sink layer while the mesa shaped diodes are supported by the support layer for subsequent processing. Upper electrodes for the diodes are formed interconnecting the mesa shaped diodes. The individual diodes, or sets thereof, are then separated from the support structure to provide individual single diode, or multiple diode devices.

Abstract: A radio frequency receiver wherein received signals are directed to a mixer through a pair of signal channels, the bandwidth of one of the pair of signal channels being a selected narrow portion of the bandwidth of the other one of the pair of signal channels. With such arrangement a received signal within a wide band of frequencies is passed to the mixer through both channels to become homodyned to a fixed intermediate frequency signal. Noise received by the wide bandwidth receiver while also passed through the both channels is mixed with only a narrow portion of itself, and hence the amount of noise at the fixed intermediate frequency is reduced with the result that the sensitivity of the receiver is correspondingly increased. An instantaneous frequency measuring unit is also fed by the selected narrow portion of the wide bandwidth signal channel to determine the frequency of the received signal with improved sensitivity.