Abstract: In an FM detector circuit, a phase-shifting circuit is constituted by integrating circuits each consisting of a transconductance amplifier and capacitor. The phase-shifting circuit being arranged to cause limiter signal to be phase-shifted by 90 degrees at center frequency. A multiplying circuit is provided which is arranged to be provided with said limiter signal and output of said phase-shifting circuit, thereby effecting phase-detection of said limiter signal. Further, an error amplifier is provided which is supplied with a smoothed version of detection output derived from said multiplying circuit. The arrangement is made such that output of the error amplifier is applied to the transconductance amplifiers constituting said phase-shifting circuit.

Abstract: A polar leapfrog filter includes at least one polar network. The polar network comprises a differentiator constituted by an operational amplifier having input and output terminals, and a first integrator formed by a first capacitor for providing negative feedback to the operational amplifier and a first variable transconductance amplifier; and a second integrator formed by a second capacitor for providing negative feedback to the first integrator, and a second variable transconductance amplifier. A differentiator is provided at each of the input and output portions of the filter, and a third differentiator is provided immediately preceding the output side differentiator. In the case where two or more said polar networks are incorporated, an additional differentiator is provided between the polar networks. The sum of the number of the circuits constituting the differentiators and the number of the polar networks is selected to be even and equal to the order of the filter.

Abstract: A polar leapfrog filter includes at least one polar network. The polar network comprises a differentiator constituted by an operational amplifier having input and output terminals, and a first integrator formed by a first capacitor for providing negative feedback to the operational amplifier and a first variable transconductance amplifier; and a second integrator formed by a second capacitor for providing negative feedback to the first integrator, and a second variable transconductance amplifier. In the case where two or more said polar networks are incorporated, an integrator is provided between adjacent ones of the polar networks. The total number of all the circuits is selected to be odd and equal to the order of the filter. The adjacent ones of the circuits are connected in such a manner that leapfrog type negative feedback is effected.

Abstract: A polar leapfrog filter includes at least one polar network. The polar network comprises a differentiator constituted by an operational amplifier having input and output terminals, and a first integrator formed by a first capacitor for providing negative feedback to the operational amplifier and a first variable transconductance amplifier; and a second integrator formed by a second capacitor for providing negative feedback to the first integrator, and a second variable transconductance amplifier. An integrator is provided at each of the input and output stages, and a third integrator is provided immediately preceding the output side integrator. In the case where two or more said polar networks are incorporated, an additional integrator is provided between the polar networks. The total number of all the circuits is selected to be even and equal to the order of the filter.

Abstract: An electric circuit apparatus comprises an electrically connecting member including a holding body made of an electrically insulating material and a plurality of electrically conductive members embedded in the holding body. First end portions of the electrically conductive member extend through a first side of the holding body and second end portions of the electrically conductive member extend through the other side of the holding body. A plurality of electric circuit components are connected to the second end portions of the electrically conductive members.

Abstract: An all-pass filter includes an adder which comprises a variable conductance amplifier and a capacitor connected to the output terminal thereof. The adder is being arranged to add the output of a band pass filter and an input signal together.

Abstract: A method of producing an electrical connection member includes the steps of applying a carrier containing a light-sensitive resin onto a substrate member, forming holes in portions of the carrier to form a pattern and expose the substrate member in the holes, filling each hole in the carrier with an electrically conductive member, and removing the substrate member from the carrier. With this method, it is possible to easily produce electrical connection members in which high density electrical connecting portions can be provided and in which the reliability and security of electrical connections can be improved.

Abstract: An electric circuit device comprises an electric connecting member comprising a support member made of an electrically insulating material and a plurality of electrically conductive members buried in the support member and being isolated from one another. The ends of one side of the electrically conductive members are exposed at one surface of the support member, and the ends on the other side of the electrically conductive members are exposed at another surface of the support member. A first electric circuit component has connecting regions connected to the one set of ends of the electrically conductive members, and a second electric circuit component has connecting regions connected to the other set of ends of the electrically conductive members. Some of the electrically conductive members can be arranged in a zigzag pattern, and the pattern of the exposed ends of at least one electrically conductive member is wave-like or S-like.

Abstract: A polar leapfrog filter includes at least one polar network. The polar network comprises a differentiator constituted by an operational amplifier having input and output terminals, and a first integrator formed by a first capacitor for providing negative feedback to the operational amplifier and a first variable transconductance amplifier; and a second integrator formed by a second capacitor for providing negative feedback to the first integrator, and a second variable transconductance amplifier. A differentiator is provided at each of the input and output stages of the filter. In the case where two or more said polar networks are incorporated, an additional differentiator is provided between the polar networks. The total number of all the circuit units constituting the filter is selected to provide odd order and equal order for the filter. The circuit units are connected in such a manner that leapfrog type negative feedback is effected.

Abstract: An active filter circuit comprises a differentiator constituted by an operational amplifier having an input terminal and output terminal, and a first integrator constituted by a first capacitor and a first variable conductance amplifier for providing negative feedback to the operational amplifier and a first variable conductance amplifier; and a second integrator constituted by a second capacitor and a second variable conductance amplifier for providing negative feedback to the first integrator. The active filter circuit is arranged such that a damping pole is set up at a predetermined frequency by adjusting operating currents of the first and second variable conductance amplifiers.

Abstract: A process for preparing an electrical connecting member having a holding member comprises an electrically insulating material, a plurality of electroconductive members equipped in the holding member under the state mutually insulated from each other, one end of the each electroconductive member being exposed at one surface of the holding member, and the other end of the each electroconductive member being exposed at the other surface of the holding member, the process comprising the steps of:(A) constituting a matrix member by providing a photosensitive resin which becomes the holding member on both surfaces of a base member, respectively;(B) exposing and developing the respective photosensitive resins to form a plurality of holes through the photosensitive resins, thereby having the base member exposed;(C) curing the photosensitive resins;(D) etching away a part of the base member exposed;(E) filling an electroconductive member into the holes formed in the holding members coplanar with or protruded from the

Abstract: A leapfrog filter comprises a first integrator made up of a first operational amplifier and a first capacitor connected to output terminal of the first operational amplifier; a second integrator made up of a second operational amplifier and a second capacitor connected to inverting input terminal and output terminal of the second operational amplifier; and a variable current source circuit. The first operational amplifier has the output terminal thereof connected to non-inverting input terminal of the second operational amplifier. The second operational amplifier has the output terminal thereof connected to inverting input terminal of the first operational amplifier. An input terminal is connected to non-inverting input terminal of the first operational amplifier; and output terminal connected to the output terminal of the second operational amplifier.

Abstract: A process for preparing an electrical connecting member having a holding member with an electrically insulating material, and a plurality of electroconductive members. The electroconductive members are mutually insulated from each other and one end of each of the electroconductive members is exposed at one surface of the holding member and the other end is exposed at another surface of the holding member. A holding member is formed by forming a layer on a base member with the holding member having a photosensitive resin on the uppermost surface of the layer. The holding member is exposed and developed by forming a plurality of holes through the holding member, thereby exposing the uppermost surface of the layer. A part of the exposed layer is etched away and the holes on the holding member are filled with an electroconductive member. The remaining layer and base member are then removed.

Abstract: A method of making an electric circuit device by connecting first and second electrical circuit components through an electrical connecting member. The method comprises effecting internal heating such as supersonic heating, high-frequency induction heating, high-frequency dielectric heating or microwave heating at first connecting regions between the connecting portions of the first electrical circuit component and the first ends of the electrically conductive members of the electrical connecting member. The same internal heating may also be effected at second connecting regions between the connecting portions of the second electrical circuit component and the second ends of the electrically conductive members of the electrical connecting member. In consequence, alloying takes place in first and second connecting regions so as to connect the first and second electrical circuit components through the electrical connecting member.

Abstract: In a tuning circuit, use is made of a current-controlled type variable inductor comprising a tuning coil and a control coil for controlling the magnetic flux density of the tuning coil. The tuning coil is connected in series with the antenna; a tuning capacitor is connected to each end of tuning coil; and by controlling a current flowing through the control coil, magnetic flux induced in the tuning coil is increased, decreased or cancelled so that the magnetic flux density of the tuning coil is adjusted to control the inductance thereof, thereby permitting the tuning circuit to be tuned to any desired frequency in the receiving frequency band.

Abstract: A leapfrog filter comprising a first and a second integrator each consisting of an operational amplifier and integrating capacitor. The leapfrog filter includes differential amplifier which is arranged to differentially supply current to the first and second integrators through a first and a second current source circuit respectively; and a third current source circuit for adjusting the sum of currents supplied to the first and second current source circuits, wherein characteristics such as the center frequency f.sub.o and quality factor Q of the leapfrog filter are controlled by adjusting the respective current values.

Abstract: Two embodiments of off the road motorcycles embodying low pressure balloon tires. In each embodiment, an improved final drive arrangement is provided that includes a ring gear that is disposed substantially inwardly of the outer periphery of the rear wheel to provide a relatively compact final drive housing to facilitate leaning of the motorcycle. In one embodiment, the ring gear is driven by a pinion gear that is directly affixed to one end of a drive shaft and which is driven at its other end from the engine by means of a chain drive. In the other embodiment, the ring gear is driven by a pair of transfer spur gears from a drive shaft that is articulated and which is driven directly from the engine output shaft.

Abstract: A method of producing electrical connection members includes the steps of forming a carrier on a first electrically conductive member, etching holes in portions of the carrier to expose first electrically conductive member in the holes, and etching the portions of the first electrically conductive member which are exposed in the respective holes to form recesses in the first electrically conductive member so that each of the recesses has a diameter larger than the diameter of a corresponding one of the holes. The respective holes formed in the carrier are filled with second electrically conductive members, and then the first electrically conductive member is removed from the carrier. With this method, it is possible to easily produce electrical connection members in which high density electrical connecting portions can be provided and in which the reliability and security of electrical connections can be improved.

Abstract: An automobile antenna system for diversity reception includes high-frequency pickups for effectively picking up the high-frequency surface currents which are induced on a vehicle body by broadcast waves and which flow concentratedly on the marginal edge portions of the vehicle body. The high-frequency pickups are disposed on both sides of the roof panel at the rear and front portions of a vehicle body in close proximity to the marginal edge and in a concealed state without any external exposure. The pickup that enjoys the optimum reception at any given time is selected from among the pickups by automatic changeover.

Abstract: In order to enable piping work associated with the duct mounting to the carried out easily, to obtain a large heat radiation area, and to enhance the efficiency of the heat radiation, there is provided a duct mounting structure for a prefabricated curtain wall with an air conditioning system having a frame body for a curtain wall unit formed by left and right hollow vertical member, upper and lower horizontal members, all of which are constituted of metallic extruded section members and which are framed with one another in a rectangular shape, and a hollow horizontal muntin constituted of a metallic extruded section member extending transversely between the left and right hollow vertical member and connected thereto. Respective hollow inside portions of the frame body constructing members and the horizontal muntin are arranged to intercommunicate so as to cause conditioned air to flow through a duct into the hollow inside portions.