Abstract: A surface acoustic wave device is disclosed for use in a communication apparatus where the surface acoustic wave device has a multiple of surface acoustic wave elements with different filter characteristics formed on mutually distinct piezoelectric substrates. The different filter characteristics combine to form filters having desired filter characteristics.

Abstract: A technique is disclosed to independently tune different sections of a filter by momentarily frequency shifting a first tuned section, preferably by shorting certain nodes in the first tuned section, such that response of a second section can be determined and independently tuned. The first section is returned to normal operation after the second section is tuned.

Abstract: A dual-mode filter has a dielectric resonator in each cavity, with each resonator containing one or more apertures. The aperture or apertures are located to shift a resonance frequency of a spurious mode to a higher frequency range distance from a principal mode. The principal mode can be an HEH.sub.11 mode and the spurious mode can be an HEE.sub.11 mode or vice-versa. The dielectric resonators can be a solid block or two or more discs that are laminated to one another. Previous dual-mode filters cannot attain the results required for current satellite systems.

Abstract: An EMI bead core filter is used to suppress or reduce a noise by utilitizing the characteristics of increasing the impedance in high frequency, which comprises of a ferrite core, a lead wire and a coating layer. The coating layer deposited on the upper portion of the core and the bending of the wire to adhere between the core and the wire by coating with an epoxy powder. A process of this invention comprises of the steps of bending, inserting, tapping, heating, coating, packaging and hardening, and especially the coating is accomplished by carrying repeatedly out four times, that is, upon preheating at 380.degree. C. and heating at 335.degree. to 340.degree. C. A coating apparatus has a vacuum device, a powder chamber and two heaters. The filter has a high impedance and a small size.

Abstract: A laser tuning method for tuning a ceramic passband filter comprises forming an untuned filter that includes at least one metallized element, such as a resonator pad, formed of an undersized metal plate. A thick film of a metal powder paste is applied to the filter adjacent to the undersized plate. The paste film is scanned with a laser beam to sinter the metal particles into an integral plate, thereby adjusting the size and shape of the element to obtain a desired performance characteristic. In one aspect of this invention, an output signal in response to a test signal is monitored while laser scanning the paste film, whereupon the laser beam is discontinued when the desired characteristic has been obtained.

Abstract: A dielectric filter having a plurality of dielectric coaxial resonators and a multilayer substrate comprising a plurality of dielectrics layers and a plurality of electrically conductive patterns, wherein the dielectric coaxial resonators are positioned against a front surface of the multilayer substrate and are electrically connected in parallel through first capacitors formed by the electrically conductive patterns of the multilayer substrate, a series connection of a second capacitor, a strip line and a third capacitor or a series connection of a second capacitor, an inductance element and a third capacitor formed by the electrically conductive patterns of the multilayer substrate is electrically connected in parallel relative to the first capacitors. The filter is small and can be manufactured in a reduced number of man-hours.

Abstract: This invention discloses a band-stop filter, which has multiple sections of non-uniform and unbalanced microstrip transmission line. Such a structure can optimize the characteristics and maximize the matching frequency range. The total length of the filter can be reduced to a half of that of a conventional filter, and the insertion loss in the pass-band is reduced to a third of that of a conventional filter. Besides, this invention suggests a structure which does not require the inward etching of the microstrip line. Instead, the microstrip line itself is used directly as the building element of a spur-line filter. Thus, the tolerance in fabrication can be greatly relaxed without effecting the required characteristics.

Abstract: A first dielectric block or blocks have a cut out portion and the cut out space is filled with a second dielectric block. A bypass pattern is formed on the second dielectric block and is capacitively coupled with two resonance elements formed on the first dielectric block or blocks. the dielectric filter is compact, and the position and intensity of attenuation poles can be freely designed and easily adjusted.

Abstract: A circuit element utilizing a magnetostatic wave is disclosed which uses a magnetostatic-wave resonator having a structure wherein a thin YIG (yttrium iron garnet) film is formed on a non-magnetic substrate such as a GGG (gadolium gallium garnet) substrate and defining a wave propagation plane. In this resonator, at least a part of end faces of the YIG film are inclined at an angle of 2.degree. or more to a plane perpendicular to the wave propagation plane to suppress the generation of unnecessary spurious modes in a wide frequency range.

Abstract: A multi-resonator notch filter incorporates a variable impedance transmission line with impedance values going from a relatively low value and increasing upward to a relatively high value then back down to a relatively low value again. A plurality of resonant cavities is coupled to the relatively high central impedance line section of the filter at odd multiples of quarter wavelength intervals. Other resonators can be coupled to lower impedance sections of the transmission line. The locations of selected resonators on the quarter wavelength intervals can be altered thereby increasing and decreasing the nominal quarter wavelength intervals of selected internal pairs by a predetermined amount thereby providing acceptable levels of performance with fewer resonators.

Abstract: A capacitor filter circuit including an input electrode, an output electrode, a ground electrode, a first input capacitor connected between the input electrode and the ground electrode and a second input capacitor connected in parallel with the first input capacitor between the input electrode and the ground electrode. Also included in the circuit is a first output capacitor connected between the output electrode and the ground electrode, a second output capacitor connected in parallel with the first output capacitor between the output electrode and the ground electrode and an inductive means coupled between the input electrode and the output electrode.

Abstract: A harmonic and subharmonic filter is coupled between a high power RF energy source and a non-linear RF load via a matching network, such as a plasma chamber. The filter passes high power RF energy in a band centered on a predetermined radio frequency, i.e., 13.56 MHz, but blocks and attenuates out-of-band energy at frequencies which are multiples of or fractions of the predetermined frequency. The harmonic and subharmonic filter comprises an input terminal, an output terminal, a series LC resonance path connected between the input and output terminals, and tuned to the predetermined radio frequency, a series resistive path formed of first and second resistors, and a parallel LC resonance path between the junction of the two resistors and ground.

Abstract: A dielectric resonator has a pattern of metallic micro-wave strips deposited onto a dielectric substrate having a high relative permittivity. The pattern is of a generally annular shape and has a slot formed in the annular pattern. The resonator includes an positive feedback circuit coupled thereto having an active element, such as a transistor, and is usable, for instance, as a band-cut off or band-pass filter.

Abstract: A filter circuit includes a first pair of RF propagation networks disposed to provide a first coupled line section having a first electrical pathlength at a first frequency, means for providing a signal path between an input port of the filter and the first coupled line section and a second pair of RF propagation networks disposed to provide a second coupled line section having a second different electrical pathlength at the first frequency with a first one of the first pair of RF propagation networks coupled to a first one of the second pair of RF propagation network. The filter circuit further includes a third pair of RF propagation networks disposed to provide a third coupled line section having a third different electrical pathlength at the first frequency with a second one of the second pair of RF propagation networks coupled to a first one of the third pair of RF propagation networks and means for providing a signal path between the third coupled line section and an output port of the filter.

Abstract: A delay line device for delaying signal transmission, comprising a dielectric layer, a grounding electrode layer disposed on one surface of the dielectric layer, a strip line conductor layer disposed on the other surface of the dielectric layer, an input terminal and an output terminal respectively connected to the strip line conductor layer at two positions, and a delay time adjusting electrode connected to at least one of the input and output terminals, a capacitance of which influences a delay time being obtained between the delay time adjusting electrode and the grounding electrode layer. The capacitance of the delay time adjusting electrode is adjustable, thereby permitting adjustment of the delay time.

Abstract: A magnetron for a microwave includes a pair of choke coils wound around only one core in same direction thereby forming a unique type choke coil. Ends of the unique type choke coil are connected among a lead-through capacitor, a center lead and a peripheral lead respectively so that the filter circuit includes jointly the unique choke coil. As a result, the magnetron can eliminate radio frequency noise, reduce the heating caused from a power supply, and reduce the volume of the filter box.

Abstract: An agile microwave filter tunable by ferrite is constituted as a filter having dielectric confinement resonators and as a result comprises an evanescent mode waveguide and resonant cylinders placed in the waveguide. In addition, the cylinders are made of ferrite and means are provided for applying an adjustable magnetic field thereto, thereby enabling the center frequency of the filter to be shifted.

Abstract: A switchable dual mode directional filter system includes two identical filters coupled to input and output waveguides at the same plane in phase quadrature. Each waveguide has two ports through which the signal enters and exists. One of the filters has a switching device incorporated therein for selecting the desired output port. One embodiment of the switching device includes a pair of coupling members that extend radially inward within the cavity of the filter toward a central axis. These coupling members define two coupling positions for the system. Solenoids move the two coupling members into and out of the cavity of the filters. Only one coupling member is used at a given time. This switching device is designed to change the polarity of one of the components of the signal wave to change its wave characteristics in the output waveguide. As a result, the desired port of the output waveguide can be selected easily.

Abstract: A parallel connection multi-stage band-pass filter including an input terminal and an output terminal for signals, a plurality of resonators respectively having resonator frequencies different from and close to one another which are electrically connected in parallel to each other between said input and output terminals.

Abstract: A reflection-type phase shifter employs an artificial delay line which is constructed of high impedance transmission line sections for the series inductive elements in the transmission line. Each junction between inductances in the transmission line is associated with a separate FET pair. The FET pair includes a first FET having the source to drain path coupled between the junction and a point of reference potential. The gate electrode of the first FET is coupled via the source to drain path of a second FET to the point of reference potential. The gate electrode of the second FET is coupled to one terminal of a resistor which is of a larger value compared to the ON resistance of the FET. This resistor has another terminal coupled to a control voltage source.