Abstract: A first responder for transmitting an identification signal in response to a microwave interrogation signal comprises an electric power receiving circuit for receiving the interrogation signal to produce a dc power, having a microstrip line antenna having a trapezoid shape whose upside has a width from 1/2 to 1/4 of a wavelength, and a rectifying circuit. The rectifying circuit may be modified. A second responder comprises an electric power receiving circuit having a microstrip line antenna from the received microwave signal, a power supplying circuit for supplying a dc power in the vertical and horizontal positions of the responder against a polarizing plane of the microwave signal, an identification signal generation circuit for transmitting an identification signal through the antenna with given polarization plane by detecting the responder attitude.

Abstract: A push-push oscillator comprises: a resonator having a transmission line and a capacitance connected to the transmission line in parallel; an oscillator for producing two outputs having an antiphase relation therebetween in response to the resonator; and a differential signal producing circuit for producing a differential signal in accordance with difference between these two outputs. These outputs can be obtained from the resonator. The transmission lines comprise strip line or microstrip line which is curved to form an open loop. The transmission line may be made of a dielectric material and is curved to form an open loop whose both ends are connected to a capacitance. The resonator may further comprise two second transmission lines, each provided to an end of the transmission line, these two second transmission lines facing each other with a given distance therebetween, the distance and length of the second transmission lines being determined such that necessary capacitance is provided.

Abstract: A tape scraper is made of a block of material having first and second planar internal surfaces disposed at an angle relative to each other. An external surface of the block is ground by a grindstone, while the block is rotated about an axis. The axis is located in a plane bisecting the angle between the planar internal surfaces. Grinding is continued until a groove between the two planar surfaces is opened to form facing knife edges. Rigid alignment of the knife edges is maintained by portions of the material which remain after grinding that connect the separated portions together.

Abstract: A linear motion guide unit having a rack and pinion mechanism for preventing slippage in relative sliding motion is provided. The linear motion guide unit includes a table elongated in shape and having a generally U-shaped cross section and a bed elongated in shape and having a generally U-shaped cross section which is oriented with its inner surface facing the inner surface of the table. The unit also includes a plurality of balls sandwiched between the table and the bed so as to provide a rolling contact therebetween. Also provided is a retainer having a horizontal section and a pair of vertical sections extending from the opposite sides of the horizontal section and formed with a plurality of windows for receiving therein the balls. The horizontal section of the retainer is formed with a slot and a pinion gear is rotatably supported on the retainer as extending partly through the slot and at the center in the widthwise direction of the retainer.

Abstract: A resonator having a strip line, the strip line comprising: a first portion forming an open loop; and two second portions, each provided to each end of the first portion, the second portions facing each other with a given distance therebetween, the distance and length of the second portion being determined such that necessary capacitance is provided. The capacitor is provided instead of a discrete capacitor for saving space and for reducing dielectric loss therein. A second resonator further comprises second and third capacitor having a semicircle strip-line patterns for providing capacitances between ends of the first portion and grounded planes which decrease the resonance frequency so that size of the second resonator are reduced. A third resonator also comprises the first capacitor, but arranged outside of the first portion. Capacitance of the first capacitor can be increased by teeth provided to the second portions.

Abstract: There is disclosed herein a millimeter-wave/submillimeter-wave oscillator comprising a mirror and a diffraction grating so as to form a Fabry-Perot type resonator. The mirror, being a concave mirror or a plane mirror, and the diffraction grating are disposed in facing and spaced relation to each other. The diffraction grating has a plurality of channels extending in a direction normal to a surface of the mirror so that the oscillator has a comb-like configuration. A plurality of oscillation elements are mounted on portions within the channels of the diffraction grating.

Abstract: A coaxial dielectric resonator for VHF and/or UHF band comprising a generally cylindrical dielectric having inner surface and outer surface. The inner and outer surfaces of the dielectric are respectively covered by outer and inner conductors and these conductors are connected at one end of the dielectric. An adjusting screw for adjusting resonance frequency is provided at the other end of the dielectric which is covered by a lid while holding a gap between the adjusting screw and the lid. A microwave filter using a plurality of the coaxial dielectric resonator is further described.

Abstract: A band-stop filter for VHF-UHF band comprises at least three series resonance circuits and at least two transmission lines each connected between the series resonance circuits. One of the transmission lines, which is connected to the input terminal of the band-stop filter, has an electrical length which is shorter or longer than the quarter wavelength of the center frequency of the stop band by more than 20 but less than 50 percent. When a band-stop filter comprises four transmission lines, one of the transmission lines, which is connected to the output terminal of the band-stop filter, has the same length as the transmission line connected to the input terminal. With this arrangement, the band-stop filter exhibits a sharp attenuation characteristic in a frequency range below or above the center frequency.

Abstract: In a coaxial filter arrangement having a plurality of coaxial resonators each having a bottomed metallic cylinder interposed between a dielectric plate and one end of a center conductor of each resonator, the peripheral wall portion of the metallic cylinder is received in the bore of an outer conductor having an open end and a closed end connected to the other end of the center conductor. In one embodiment, the bottom of the metallic cylinder has a convex portion at its center so that the bottom center projects outwardly. In another embodiment, an annular metallic member is interposed between the dielectric plate and the outer surface of the flat bottom of the metallic cylinder. Since the distance between bottoms of metallic cylinders of adjacent resonators is made large with this arrangement, influence due to leakage flux of electromagnetic field is small, while stray capacitance is negligibly small, thereby providing a filter having high performance and low loss.