Abstract: A switching circuit comprising a substrate of semiconductor material, a first switching device (e.g., a diode) formed in a first region of the substrate, a second switching device (e.g., a diode) formed in a second region of the substrate integral with the first region, the second switching device being electrically coupled to the first switching device, and means, disposed in the substrate, for electrically isolating the first substrate region from the second substrate region.

Abstract: A door assembly for a high temperature oven is disclosed, including a door frame having a cavity which is at least in part wedge-shaped and having apertures through the frame with a resilient seal surrounding the aperture. A door is located within the cavity, and moves in a generally vertical direction from an open position wherein the door is out of contact with the resilient seal and is displaced from the area between the apertures to provide unimpeded passage therethrough, to a closed position wherein the wedge shape causes the door to firmly seal against the resilient seal so that the substantial escape of gases through the closed door does not occur.

Abstract: An oven system for the continuous firing of bindered ceramic materials includes a conveyer, a burnout section, and an oven section. The burnout section burns binder out of the ceramic materials without substantial firing of the ceramic materials. The oven section fires the ceramic materials at a temperature of 800.degree. C. to 1600.degree. C. in an oxygen atmosphere. The oxygen in the oven is at a pressure of at least one-half atmosphere, so that the ceramic products are at least substantially in the oxide form and have a density of at least 98% of the theoretical density. The oven has a wedge shaped door which interacts with a wedge shaped cavity to seal the door.

Abstract: A method for dimple free guillotine cutting of multiple wall tube which involves first cutting a transverse notch substantially completely through the outermost tube wall and secondly cutting a notch through the path of the first notch but of greater depth to extend partially through the innermost tube wall. The cutoff function is then finalized by means of a guillotine blade which enters through the coextensive notches. Both pull-across and thrust blades for carrying out the method are disclosed.

Abstract: A voltage controlled oscillator includes a VCO chip that is a monolithic circuit with a Gunn diode and varactor diode intercoupled by a resonant circuit. A detector/discriminator/power divider chip is coupled to the VCO chip through a directional coupler and is a monolithic circuit having a pair of discriminator diodes and amplitude detector diode on a semi-insulating substrate with associated circuit components. Connected-together electrodes of the discriminator diodes are connected to one output of the power divider. An electrode of the amplitude detector diode is connected to the other output of the power divider. Stagger-tuned resonant circuits are coupled to the other electrodes of the discriminator diodes. Conducting portions forming low pass filters couple the amplitude detector diode and the discriminator detector diodes to respective outputs.

Abstract: A ram-driven cut-off die set of the double-cut type in which sections of tubing are successively severed from a continuous length of tubing by a notching cut followed by a severing cut wherein improved means are provided for mounting and guiding the notching blade in its notching movement. The improved mounting means comprises an upper shaft positioned over the tube path and extending from one side to the other side of the path, a lower guide shaft positioned totally on the one side of the tube path, and a cross slide having a relatively long upper portion slidably journalled on the upper shaft and a relatively short lower portion journalled on the lower guide shaft to maximize the magnitude of the journalling support provided to the notching blade as it makes its reciprocal movement across the tube path to accomplish the notching cut.

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 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: A backfire feed antenna has a parabolic reflector with a ring-focus at the reflector focal point comprising a dielectric waveguide having a stem portion and a cap portion with a pointed end and most of the stem portion inside a conducting tube along the axis of the parabolic reflector. The outer surface of the cap portion is concave outward and convex inward and covered with a conducting layer. A curve between a parabola and hyperbola defines the surface. The cap portion has a conical surface extending between an annular surface at the junction between the stem portion and the cap portion and an axially extending circumferential surface surrounding the conducting layer. The inside end of the dielectric waveguide is pointed.

Abstract: An indexible notching blade for a double-cut tube cut-off die set wherein the notching blade is triangular in configuration to provide three individual cutting edges. Both pull-across and thrust type configurations are disclosed.

Abstract: A modified TO-8 package has a kovar header supporting an FET amplifier hermetically sealed by a cover welded along the seam between the cover edge and header edge. The header is formed with three circular openings in space quadrature about the package axis. A circular copper spacer contacts the header and is formed with channels extending radially outward from the header openings to define with the openings three lead channels. A lead having a right angle bend is seated in each channel having an upstanding pin portion above the header. The volume between the lead and the header is filled with hermetically sealing low expansion borosilicate glass. The remainder of each channel is filled or coated with nonconductive epoxy. The depending portions of the leads are flush with the bottom of the copper spacer.

Abstract: A hybrid ring mixer includes an annular conducting ring on a gallium arsenide substrate coated on the bottom with a conducting layer to comprise a strip transmission line. Three conductors spaced by 120.degree. extend radially outward from the annular ring to define local oscillator, signal input and i-f ports, respectively. A pair of conductors spaced by substantially 120.degree. extend radially inward to comprise diode ports. A conducting surface inside the annular ring is grounded and has circular sectors of different radius bounded by radii extending from the center of the ring and bisecting the signal and local oscillator ports, respectively. The sector of larger radius is located in the 120.degree. sector between the signal and local oscillator ports. Mesa diodes are connected between each of the diode ports and the sector of smaller radius.

Abstract: In a microwave circulator having a ferrite core axially aligned along the axis of a junction of waveguides and surrounded by an insulating sleeve seated in counterbores in opposed metal transformers seated in opposed waveguide broad walls, one end of the ferrite core is highly polished and bonded with a silver epoxy to one of the metal transformers and spaced from the other by an insulating disk. Opposed rare-earth cylindrical magnets embedded in the broad wall axially aligned along the junction axis bias the ferrite core and establish a magnetic field along the junction axis inside the ferrite core.

Abstract: Apparatus for cutting heavy wall tubing including vertical and horizontal mechanically driven rams operated in sequence to drive blades fully through a tubing section. Notching blades cut shallow notches in the section in advance of the main blade entries thereby to prevent dimpling.

Abstract: A cutoff apparatus for tubing and the like wherein a single electric motor is used to accelerate the apparatus into synchronous movement with the tubing and is also used to power the cutoff apparatus during the work stroke. A rotary crank is connected to the output shaft of the motor and to a control linkage which substantially reduces the cutoff work stroke length while at the same time preserving substantially the entire acceleration travel distance.

Abstract: Tube cutoff apparatus of the double cut type wherein a horizontal blade passes across and notches a section of tube wall prior to the entry of a vertical severing blade. The horizontal blade holder assembly comprises a carriage which is interconnected with the base by means of a pair of parallelogram links. In one embodiment the horizontal blade holder assembly is driven through an arcuate path of travel by a depending dogleg cam which is mounted on the upper platen assembly of a die set. In a second embodiment the horizontal blade holder assembly is driven by a linkage including a triangular link and a drive link connected to the upper platen assembly. The result in both cases is to drive the horizontal blade holder assembly through an arcuate path which carries it downwardly and away from the path of the vertical blade in a minimum vertical stroke length.

Abstract: A linear accelerator system for linearly advancing an electrically conductive, elongate workpiece, such as tubing, along its longitudinal axis toward a cutoff station or the like includes a helically configured electrical coils concentrically disposed around the workpiece for inducing an electromagnetic field which imposes an axial force on the workpiece. An adjustable stop assembly engages one end of the workpiece to allow selection of the length to be cut. A switch operated by the stop assembly produces a first control signal for controlling a relay which deenergizes the coil; the relay reenergizes the coil in response to a second control signal produced by another switch which senses the completion of the cutoff operation. Sleeves removably mounted on the coil to accommodate workpieces having various diameters. In lieu of the stop assembly, a length encoder may be optionally employed in combination with the accelerator or a separate retarding device to control feed length.

Abstract: Method for cutting heavy wall steel tubing. The tubing is notched and cut through along a vertical axis but the blade is narrower than the interior diameter so as to leave the side walls uncut. A side wall is preferably notched during the first cut. Thereafter, a second blade is driven horizontally through the side notch to complete the cut.

Abstract: An N or N.sup.+ type semiconductor substrate has a P-type layer diffused therein to form a PIN junction that is etched out between adjacent mesas and filled in with glass to form adjacent diodes between top and bottom surfaces of the substrate. The bottom surface is metallized. The top surface carries a conducting layer interconnecting the adjacent P-type portions of the mesas. This conducting layer has end portions connected to a respective diode of end width and length joined by an intermediate portion of intermediate width and length.

Abstract: Several strips of resistive material are deposited on a top surface of a dielectric substrate having an opposite bottom surface substantially covered by a conducting material. A strip of conducting material is also deposited on the top substrate surface in electrical contact with the strips of resistive material. At least one of the strips of resistive material is electrically connected to the conducting material on the bottom substrate surface.