Abstract: A tubular assembly for use in an RF filter having an internal cavity. The tubular assembly includes a hollow tube and a flare positioned inside the hollow tube for mounting the hollow tube onto the filter housing. The flare includes at least two engagement surface portions which engage the inner wall of the hollow tube. During assembly, the flare engagement surface portions expand thereby locking the hollow tube on the filter housing.

Abstract: An antenna system includes a substantially enclosed waveguide and a container including an inlet and an outlet. The inlet is fluidly connected to ambient air. The outlet is fluidly connected to the waveguide. A check valve is disposed within the container. The check valve is configured for allowing air passage from the inlet to the outlet while preventing air passage from the outlet to the inlet. A desiccant is disposed within the container.

Abstract: The filter includes a housing (13) defining a cavity (14). The housing has a fluid inlet orifice (22) and a fluid ou let orifice (24) therein. At least one resonator (16), which is sized to receive and pass a radio frequency signal, is disposed in the cavity. A dielectric fluid (18) fills the cavity. The fluid inlet orifice is configured to supply a first quantity of the dielectric fluid to the cavity and the fluid outlet orifice is configured to remove a second quantity of the dielectric fluid from the cavity, so that the dielectric fluid is continuously replaced.

Abstract: A low inductance interconnect suitable for microwave frequency interconnect applications. The invention provides a low inductance interconnect structure providing interconnection operable from DC to beyond 100 Ghz. The structure may be in the form of a resilient comb, and can be cut from thin sheet metal with a Wire Electric Discharge Machine (EDM). Other resilient forms include spring structures, resilient canes and conductive fuzz.

Abstract: Inexpensive and reliable apparatus for blanking the signal path between an antenna and a transmitter or a receiver to protect them from harmful radiation in the absence of power forms supplied thereto. The apparatus is preferably formed as a printed circuit waveguide switch window having a plurality of parallel conductors, such as metal wires or printed circuit traces, disposed on a dielectric substrate. The waveguide switch window is secured between two sections of waveguide. The conductors have a predetermined separation and width that are designed to appear as a solid metal surface that rejects radiation over a wide bandwidth. A bias terminal is coupled to the plurality of conductors, and insulating material is disposed between the bias terminal and the conductors to insulate the top portion of the grid array from the adjacent waveguide. The lower portion of the grid array is grounded to the adjacent waveguide.

Abstract: A ground path for microwave circuits positioned on carriers is provided. A ground path is provided between a first and second carrier coupled to respective microwave circuit substrates. The first and second carriers are coupled to a base, forming an opening between the first and second carriers. A conductive element is coupled to a first microstrip transmission line on the first substrate and a second microstrip transmission line on the second substrate. A conductive spring is then positioned in the opening in order to create a ground path. The microstrip transmission line may consist of alumina or a high-frequency plastic, such as Teflon or Duroid.RTM.. The conductive spring may consist of beryllium copper. A conductive rubber material may also be positioned in the opening, contacting the conductive spring and the base.

Abstract: In high frequency apparatus such as for example an rf resonant cavity or a waveguide, it is often necessary to include a slot to permit a probe or other member to be located in the high frequency region and be moveable along the slot. Sealing means arranged adjacent to the slot and around the probe permits movement of the probe whilst minimising the open aperture area of the slot, hence preventing or reducing leakage through it. In one embodiment of the invention, the sealing means comprises a metallic mesh and in another it includes an elastomer material which is loaded with metallic material and/or carries a metallic mesh.

Abstract: Low impedance means are provided for coupling a common circuit ground of a microwave circuit to the ground potential. The low impedance means include a plurality of resonators, each having a distinct resonant frequency at which it displays a minimum impedance. The resonant frequencies of the resonators are chosen and arranged such that the resonators together operate to provide a low impedance band in the frequency spectrum within which low impedance coupling between the common circuit ground and the ground potential is achieved. In a preferred embodiment, resonators include capacitors connected in series with inductive bonding wires, and different resonant frequencies are obtained by using capacitors with different capacitance.

Abstract: Connectors on a microcomputer printed circuit board backplane receive slotted insertion of a plurality of device cards containing application specific integrated circuits (ASICs). Interconnection of the device card connectors is accomplished on the surface of the circuit board or internally with an electric line which interleaves the device card connectors providing increased conductor length between physically adjacent connectors, establishing an increased impedance level. The increased physical lengths of the intervening electric lines between the connectors provide increased impedance as seen by inserted device cards, which enhances the matching capabilities of the connectors.

Abstract: A method and multicoupler for a receiver at a base station in a cellular/PCS radio communication system includes a cooled container that is mounted on an antenna tower at the base station. The container is mounted on the antenna tower adjacent an antenna and contains thereinside a preselector filter, a highly linear amplifier, and a directional coupler that are cooled to a temperature less than 175.degree. K. and greater than 100.degree. K. A power splitter is connected between the output from the container and the radio system receiver, and is located at a ground station near the base of the antenna tower. Cooling the components inside the container, particularly the amplifier, to a temperature of about 150.degree. K. reduces the noise from the multicoupler so that base station range is extended, building penetration is improved, and subscriber transmit power may be reduced.

Abstract: A composite microwave circuit module assembly has a dielectric substrate which is formed by a lower layer, an intermediate layer and an upper layer. The lower layer and the upper layer include a lower ground surface and an upper ground surface, respectively, and the intermediate layer includes a radio frequency signal circuit formed by an active circuit element and a passive circuit element. A number of via-holes filled with metal are arranged along the radio frequency signal circuit to short-circuit the upper ground surface and the lower ground surface so as to shield the radio frequency signal circuit. An element mounting cavity is disposed on the intermediate layer with a portion of dielectric above the intermediate layer being removed, and the active circuit element is mounted on an element mounting land in the cavity. The cavity is covered by a conductor plate member.

Abstract: A method and apparatus for suppression of electrical interferences. A node or point in an electronic circuit which is emitting electrical interferences is located, and a stub member designed to be a resonant transmission line at the frequency being emitted is connected to the node for suppression of the electrical interferences. If suppression is to occur between two points that are both electrically insulated from one another, a balanced line may be used. A second parallel stub tuned to the even harmonic of the fundamental frequency may be used to suppress both the even and odd harmonics of the fundamental frequency of the electrical interference. Parallel stubs may also be used to broaden the null as in a multi-pole filter. Tuning elements such as variable capacitors may be used with the stub members to tune to the exact frequency to be suppressed.

Abstract: A cooling device for microwave circuits comprises a coaxial cable conveying very high power microwave energy, said cable consisting of a hollow, internal, central conductor with a predefined thickness and length and an external conductor within which there is placed the central conductor, said cooling device comprising an inlet channel and a return flow channel to enable the passage of a cooling fluid; said channels consisting of the central conductor which comprises, for this purpose, a strip which separates this conductor longitudinally into two conduits, each forming one of the two channels.

Abstract: A spark gap apparatus triggerable by application of a microwave pulse. The apparatus includes a first electrode including a microwave waveguide, and a second electrode spaced from the first electrode. A microwave generator is connected to supply microwave pulses to the waveguide. A main current circuit to be switched is connected to the electrodes. The first and second electrodes include components for causing the simultaneous existence of a number of spark channels therebetween in response to coupling of a microwave pulse to the waveguide so that coupling of the pulse to the waveguide results in switching of the main current circuit. A method of using the spark gap apparatus is also disclosed.

Abstract: A pressure sealed waveguide to coaxial line connection formed with a low cost, non-pressurizable waveguide to coaxial line adapter, an elastomeric sealing boot, and a specially configured mounting seat on a housing which contains a pressurizable waveguide cavity. The connection provides a low cost alternative to hermetically sealed waveguide to coaxial line adapters.

Abstract: An open waveguide electromagnetic wave radiator is used to radiate electromagnetic waves of cyclotron frequency to plasma within a vacuum container. This radiator comprises a waveguide having evacuation holes and containing ridges having a T-shaped cross-section, a radiator section connected to, and integrally formed with, the open end of the waveguide, evacuation pipes connected to the evacuation holes, a chamber enclosing the closed end portion of the waveguide and the evacuation pipes, and a pump for evacuating the chamber. The evacuation holes are made in that wall of the waveguide to which the leg of one of the ridges is connected.

Abstract: Dessicant vessel allows air to flow through desiccant from a temperature related pumping phenomena prior to entry into waveguide to guard against attenuation of microwave signal.

Abstract: A waveguide shorting device having a shorting block and a wedge is disclosed. The shorting block contains a channel which is tapered so that it matches a taper of the wedge. A screw extends through the shorting block and engages a threaded hole in the wedge. Tightening the screw causes the wedge to be received in the channel and the shorting block to expand. Expansion of the shorting block clamps the shorting piston in a locked position within a waveguide.

Abstract: A microwave tuning device including a cylindrical metal bush having an internal screw thread. A metal rod-like plunger is axially displaceable within the plastics bush. A plastics bush is fitted over one end of the plunger and fixed thereto by means of splines and grooves. The bush is inserted into the internal screw thread so as to form a corresponding mating screw thread on its outer periphery. A plurality of fingers extend from one end of the metal bush and resiliently engage the outer periphery of a plain portion of the plunger so as to provide resistance to unintentional rotation of the plunger in the metal bush and electrical interconnection therebetween.

Abstract: Disclosed is a substance-sensitive semiconductor and a method for making the same, wherein a substance-sensitive material is combined with photoresist material and applied to an electronic device structure. The substance-sensitive material may be applied before or after the photoresist material, or even may be combined with the photoresist material to form a substance-sensitive layer of photoresist material on the semi-conductor. The photoresist material is then processed, such that unwanted, or undesirable areas are free from the photoresist material and the areas of desired substance sensitivity have a fully processed photoresist layer. A further embodiment of the present disclosure provides multiple layers sensitive to different ions on a single sheet of semiconductor or electromagnetically active material.

Abstract: A grounding and supporting metal mesh provides connection between a circuit board with a cavity and a housing. The mesh is in the form of a spring made by interconnected torsional members. The mesh is plated with a metal which is compatible with the ground planes of the circuit board and housing.

Abstract: An inside collet assembly for positioning an IMPATT diode precisely axially long and coaxially of a cylindrical cavity. The assembly serves for convenient removal and repositioning of the diode within the cavity and provides effective electrical and thermal connection to the diode. The assembly is not significantly larger in diameter than the cavity and does not require surfaces producing undesired reflections of microwaves within the cavity.

Abstract: An adjustable two-port microwave network having digitally controlled switches which enable the network to be set to a plurality reflection and transmission coefficients. The network facilitates the collection of a plurality of measurements which are necessary to characterize a non-linear device. An embodiment of the network is constructed using a 3dB directional coupler feeding two identical power divider networks each comprising two cascaded directional couplers. One divider network is connected directly to the coupled port of the 3dB directional coupler and the other divider network is connected through a phase shifter to the output port of the 3dB directional coupler. The non-linear device to be characterized is connected to the input port of the 3dB directional coupler and for this application, the isolated port is terminated in its characteristic impedance.

Abstract: The impedance value of the semiconductor device usable at very high frequencies is preset during manufacture.The device comprises a Gunn or Zener diode coupled to a coaxial line. The central conductor of the line is constituted by a metal wire mandrel or a metal coating deposited on a glass fibre section.The outer cylinderical conductor is a cylindrical metal coating deposited on a ring of dielectric material, such as glass and which surrounds the diode.Application to microstrip, transmitting antenna and radial cavity circuits.

Abstract: An improved casing for an electrical component intended for use in wired television broadcast is provided with a plurality of terminal connecting plug seats having axial bores therethrough adapted to receive coaxial cable ends for connection. A predetermined number of the connecting plug seats have the axial bores thereof blocked to the passage of the coaxial cable ends by sealing members molded integrally with the casing and plug seats.

Abstract: A non-contacting electrical coupler for connecting a linearly movable radio frequency load to a stationary radio frequency power source both having a mean operating wavelength of .lambda.. The coupler comprises a pair of stationary parallel first generally tubular conductor members, each of which have an axially extending opening through the wall thereof. Terminal means are provided near a first end of the first conductor members connecting each of them to opposite sides of the power source. The first conductor members are connected together at a point located a distance substantially equal to odd multiples of .lambda./4 from the first end. A pair of movable second conductor members are disposed substantially coaxially one within each of the first conductor members. Each of the second conductor members have a length substantially equal to .lambda./4 and are axially movable within the first conductor members.