Abstract: A washing machine has a stationary tub with drain outlets at the bottom periphery. A venturi conduit extends from the bottom of the tub opening upward along the axis of the tub to produce a toroidal flow of water in an open basket in the tub seated on an annular disk surrounding the venturi opening. The annular disk is mounted on rollers at the bottom of the tub and carries permanent magnets. An annular driving member also carrying magnets is located below the bottom of the tub surrounding the conduit connected to the venturi and carries permanent magnets opposite those on the annular disk inside the tub. A pulley at the bottom of the driving member is coupled by a belt to the pulley on a drive motor. A pump is connected between the venturi and the tub outlets. A selectively operable valve controls the flow of water between the venturi and a drain outlet. This assembly is contained in a cabinet having an opening covered by a lid. The opening is large enough to allow removal and insertion of the open basket.

Abstract: A dual frequency antenna feed includes colinear axially spaced coaxial and circular waveguide cavities separated by a conducting portion having a high frequency rectangular waveguide therein extending radially outward. The coaxial cavity includes a tubular inner conductor having a polarization rotator connected to the rectangular waveguide for propagating high frequency energy. Four small coaxial transmission lines equiangularly disposed about the cavity axes and terminating in probes about a quarter wavelength from the end of each cavity intercouples the circular and coaxial cavities. The end of the coaxial waveguide cavity forms an aperture for high frequency energy from the conducting inner tube and for the low frequency energy from the region between the conducting inner tube and the cylinder surrounding the outside of the cavity. The radiating aperture is surrounded by a set of concentric conducting rings.

Abstract: An automatic dynamic equalizer includes left and right input terminals, an input adder and left and right output adders. The left and right input terminals are connected to inputs of the input adder and inputs of the left and right output adder, respectively. The output of the input adder is connected to the input of a 2:1 compressor. The output of the 2:1 compressor is connected to the input of a bandpass filter having a transmission in the low bass frequency region centered at a frequency of about 60 Hz. The output of the bandpass filter is coupled to inputs of the left and right output adders.

Abstract: A pendulum has a weight suspended from a bar at an essentially frictionless pivot near the center of gravity of the weight.

Abstract: A loudspeaker driver has a plastic basket having front and rear portions. The front portion is formed with six radial ribs extending between a central motor cup support and an annular rim. A cup-shaped front pole piece is molded into the pole support and formed with an axial groove for accommodating an axial lead extending from the front end of a voice coil that moves axially in a gap between the circumferential wall of the front pole plate and a circular rear pole plate and circular disk neodymium disk magnet sandwiched between the rear pole plate and the closed end of the front pole plate. Flat tinsel leads are crimped to ends of the voice coil and brought out through slits in the cone to terminals in opposite sides of the rear portion of the basket. The circumferential edge of the cone is clamped between the front and rear portions of the basket and ultrasonically bonded to an annular surface on the rear of the front portion.

Abstract: A flexible, circular, elastomer air foil that is a unitary structure has a central portion that droops downward when the foil is resting on a horizontal flat surface surrounded by an annular portion that is then convex on top and concave on the bottom when resting on a thicker perimetrical rim portion.

Abstract: Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing.

Abstract: Method of manufacturing silicon mesa diodes from a wafer of silicon. The surface of the wafer is coated with a first layer of silicon nitride and a second layer of silicon oxide. By masking and etching procedures, silicon nitride is left only on the portions of the surface defining the mesas to be formed. The wafer is etched to form the mesas and then treated to form a passivating silicon oxide coating at all the exposed surfaces of the wafer. The silicon nitride is removed from the upper surfaces of the mesas and metal contacts are applied to these upper surfaces. The wafer is subsequently divided into discrete dice, each containing a mesa, and the dice are mounted in suitable enclosures.

Abstract: A balance for teaching arithmetic principles has a balance arm pivotal about a central horizontal pivot axis coincident with the axis of a support rod supported in openings at the top of opposed vertical upstanding members of a support. The balance arm has a central rectangular housing and end rectangular housings at each end extending upward carrying vertical calibrations at intervals corresponding to the height of annular washers that balance the arm. A number of upstanding vertical pins similarly vertically calibrated are spaced at one-inch intervals on either side of the pivot axis at horizontal locations on the arm along respective horizontal calibration indicia of diameter corresponding substantially to the diameter of the central openings in the washers. The front face of the balance arm is transparent along its length for exposing scales on a central mandrel carrying a number of scales that may be rotated to expose a selected scale.

Abstract: A Gunn diode oscillator tuning mechanism includes a waveguide wall formed with a cavity at the outside of the wall for accommodating a tuning mechanism. A tuning rod opening extends between the inside of the waveguide wall and the cavity to snugly accommodate a sapphire rod. A holder carries the fixed end of the sapphire rod and is slidable in the cavity. The holder is formed with a circumferential sectoral slot that engages an annular ring on the rotatable translatable shaft of a micrometer adjacent to the holder seated in a holding plate at the outside of the waveguide wall.

Abstract: Apparatus for measuring or detecting a chemical entity in a liquid sample, the apparatus including a first module operationally connected to a second module, the first module having a flow passage for the sample, the flow passage including a sensor for measuring or detecting the chemical entity and pump means for advancing the sample along the flow passage, the second module including means for actuating the pump means, and the second module being connected to the first module via connecting means permitting disconnection of the first and second modules and connection of a replacement first module to the second module.

Abstract: A downlink dish receives television signals from a remote location transmitted by satellite. Satellite receivers demodulate these received signals and normally transmit them through a switch to modulators which modulate respective carrier signals to retransmit the remote program video signals over a cable to subscribers. The switch also transmits the demodulated signals to tone monitors that detect a tone indicating the beginning of a spot message interval. A computer control responds to these detected signals to enable one or more video tape machines to deliver recorded spot messages to a time base corrector that also receives portions of the program video signal adjacent the spot message interval from the switch. The time base corrector delivers the time-base-corrected video signals through the switch to the modulators for modulating a selected carrier signal with program video signals and spot message signals without flicker.

Abstract: A stereo loudspeaker system includes left and right loudspeaker cabinets each having a woofer mounted off center on the front baffle and tweeters mounted in front of the woofer with the axis of each tweeter at an angle to that of the woofer. Each cabinet includes a crossover network that intercouples the woofer and tweeter and controls the phasing of the tweeter with respect to the woofer to steer the radiation maximum of lower treble frequencies along an axis skewed from the fore-aft axis of the woofer. Left and right loudspeakers of the stereo system have symmetrical, mirror-image, crossfired, acoustic radiation patterns.

Abstract: A header has three throughpins supported by glass insulating regions in the header wall having inside and outside portions. A releasable terminal formed with a central opening is soldered to each inside portion of a throughpin and is formed with a groove that carries a lock washer or C-clip that stops a spring in compression stopped at the other end by an epoxy layer adjacent to the inside of the header wall. The assembly is formed by inserting throughpins through the openings, baking the glass insulators at 2000.degree. F., cooling this assembly, soldering the releasable pins to the inside portions at a temperature of substantially 700.degree. F. and allowed to cool. The epoxy layer is then applied at a temperature of the order of 500.degree. F. and then allowed to cool.

Abstract: A monopulse comparator is formed by milling grooves in opposed surfaces of aluminum circular blocks. The milled grooves define a number of waveguides, ports and hybrid junctions. A, B, C and D ports are coupled by respective waveguides to respective side branches in first and second hybrid rings. The series branches of these hybrid rings are coupled by respective waveguides to parallel and series branches respectively of a third ring hybrid ring. One side branch of this hybrid ring is coupled to an azimuth differential port by one of the waveguides. The other side branch is coupled to a termination by a waveguide. The parallel branches of the first and second hybrid rings are coupled by respective waveguides to respective side branches of a fourth hybrid ring. The parallel branch of this hybrid ring is coupled by a waveguide to the elevation differential port. The series branch of this hybrid ring is coupled by a waveguide to the sum port.

Abstract: An antiskid shock and vibration isolating foot is formed with an annular circumferential recess about midway between its top and bottom and made of a resilient elastomer. A threaded stud is bonded to the top of the elastomer. The upper portion above the annular recess passes through an opening in a case base until the edge around the opening resides in the annular recess. The threaded stud passes through an opening in the base of a component. The stiffness of the upper portion above the annular recess is different from the stiffness of the lower portion below the annular recess. The portion above the recess is frustoconical and that below is substantially cylindrical.

Abstract: A metallic electrode made of platinum, platinum iridium alloy, stainless steel, stainless steel alloys, titanium, titanium alloys, tantalum or tantalum alloys is coated with iridium oxide. Ir(III) trichloride is heated in 5.5M HCl until 75-80% of the solution is evaporated. Isopropyl or ethyl alcohol is added to the evaporated solution to restore the solution to its original volume. This restored acid/alcohol solution is aged for 1-2 weeks. The metallic electrode is soaked in the aged acid/alcohol solution for 16 hours, dried for one hour at room temperature and annealed in air at 320.degree. C. for 80-90 minutes.

Abstract: An instructional device is provided for tennis players to identify their stroke problems and to analyze the cause of those stroke problems. In addition, the instructional device of the present invention includes a grip analysis section to help tennis players identify and correct their grip problems.

Abstract: A rectangular plate holder is formed with an approximately square recess defined by an upstanding perimetrical wall having two top studs on one side and one top stud on an opposed side wall lapped to be coplanar in a common plane. The base plates include five and three sets of mask clamping points for defining clamping points for five and three mask sizes. Each clamp includes a clamp assembly fastened to the base having a spring-loaded lower clamping arm below an upper set screw clamping point. A handle is fixed to one side between the opposed sides having the lapped studs.

Abstract: A spray-shower pipe is equipped with flat fan nozzles having a dome-shaped indentation directed to the pipe inside and located inside a nozzle base formed with a recess that conforms with and engages the outer surface of the pipe wall and an annular extension of length corresponding to the pipe wall thickness at the circumference of the opening in which the extension is snugly seated. The front surface of the extension facing the inside of the pipe has a curvature which corresponds to the curvature of the pipe wall inside surface. The dome-shaped indentation is formed with an aperture that forms an angle with the longitudinal axis of the pipe that is slightly less than 90.degree., typically 83.degree..