Abstract: The present invention provides a clip device capable of reducing process steps for the work of connecting a base member, an opening/closing member and a double torsion spring to one another. This clip device is configured in such a manner that the base member and the opening/closing member are connected via both shaft bearings and a support shaft, and a holding portion is biased apart by the double torsion spring provided between the base member and the opening/closing member. The base member has a pair of the shaft bearings which compresses and holds the double torsion spring therebetween, positioning pieces which position the double torsion spring with respect to a direction parallel to the base member within directions orthogonal to the axial core directions of wound portions of the double torsion spring, and holes which are respectively defined between the shaft bearings and the positioning pieces and cause the tips of the double torsion spring to be inserted therethrough.

Abstract: A radio receiver having a plurality of features programmable by a user, the data relating to the programmable features defining a set-up configuration. The radio receiver includes a housing and an auxiliary memory disposed within the housing which stores a plurality of set-up configurations. A working memory is also disposed within the housing and is configured to store the set-up configuration in use by the radio receiver.

Abstract: A receiver input circuit comprises an R-? type low-pass filter, a small-capacitance type coupling capacitor element and a parallel tuning circuit. The low-pass filter has an inductor element and a first capacitor element both connected in series, and a shunt-connected second capacitor element. The first and second capacitor elements are equivalent to ones obtained by dividing a normal shunt-connected capacitor element into two. A total capacitance value thereof is selected equal to the capacitance value of the normal shunt-connected capacitor element. The parallel tuning circuit makes use of a tuning first variable capacitance type capacitor element. A second variable capacitance type capacitor element is used for the small-capacitance type coupling capacitor element.

Abstract: With the objective of providing a scanning receiver capable of capturing a target radio wave in an extremely short period of time by use of a simple constituting means, a plurality of wide frequency division bands in which a full frequency range is divided into predetermined frequency ranges are set and the field intensities of received radio waves are retrieved using the output of an intermediate frequency amplifier circuit over the set wide frequency division bands in order. Further, when a received radio wave having a field intensity greater than or equal to a prescribed level is obtained upon the above retrieval, receive frequencies are swept from one end of each of the wide frequency division bands to the other end thereof. When a target radio wave can be captured upon the above sweeping, transition to the operation of receiving the target radio wave is performed.

Abstract: The present invention provides a phase comparison signal processing circuit which processes an output rectangular wave signal of a digital phase comparator of a PLL, expands a pullable-in frequency width of the PLL and shortens a synchronization time. The phase comparison signal processing circuit includes a first signal path which is parallel-connected between a voltage shifter for converting a rectangular wave signal to a bipolar signal and an output terminal and comprises a rectifying circuit, an integration holding circuit, a differentiation circuit, a gate circuit, a voltage hold circuit and a common addition circuit, a second signal path comprising a rectifying circuit, an integration holding circuit, a differentiation circuit, a gate circuit, a voltage hold circuit and the addition circuit, and a control signal generator for individually controlling the integration holding circuits and the gate circuits of the first and second signal paths.

Abstract: The present invention provides a voltage controlled oscillator capable of obtaining an oscillation signal having a relatively low frequency with a simple circuit configuration without using AGC means and a semiconductor internal resistor. The voltage controlled oscillator includes a switching circuit which inputs therein a frequency control voltage and its inverse frequency control voltage and selects and outputs the frequency control voltage or the inverse frequency control voltage in response to an output logic state of a switching voltage generating section, and an integration circuit which integrates the output voltage of the switching circuit to form a triangular wave signal.

Abstract: The present invention provides a transmitter-receiver for short-range wireless transmission, which comprises a frequency scan signal receiving section that searches a vacant channel frequency by frequency scanning of a receiving wave, and a signal transmitting section that transmits a transmitting wave using the searched vacant channel frequency. The frequency scan signal receiving section sequentially changes a frequency of a PLL oscillator by control of a controller to thereby search the presence or absence of a receive frequency lying in a predetermined frequency band depending on an output state of a carrier detector. When the controller detects a vacant channel frequency, the frequency scan signal receiving section fixes the oscillation frequency of the PLL oscillator to an oscillation frequency corresponding to the vacant channel frequency and supplies the fixed oscillation frequency to the signal transmitting section.

Abstract: The present invention provides an active inductor comprising an input terminal, a primary all-pass type 90° phase-delayed stage constituted of discrete elements, and a phase inversion amplifying stage and including a constitution in which a signal supplied to the input terminal is inputted to the primary all-pass type 90° phase-delayed stage, a 90° phase-delayed signal obtained at its output is inputted to the phase inversion amplifying stage subsequent to the primary all-pass type 90° phase-delayed stage and phase-inversion amplified thereat, and an output produced from the phase inversion amplifying stage is feedback-coupled to the input terminal.

Abstract: The present invention provides an active capacitor comprising an input terminal, a primary all-pass type 90° phase-advanced stage constituted of discrete elements, and a phase inversion amplifying stage and including a constitution in which a signal supplied to the input terminal is inputted to the primary all-pass type 90° phase-advanced stage, a 90° phase-advanced signal obtained at its output is inputted to the phase inversion amplifying stage subsequent to the primary all-pass type 90° phase-advanced stage and phase-inversion amplified thereat, and an output produced from the phase inversion amplifying stage is feedback-coupled to the input terminal.

Abstract: A radio receiver having a plurality of features programmable by a user, the data relating to the programmable features defining a set-up configuration. The radio receiver includes a housing and an auxiliary memory disposed within the housing which stores a plurality of set-up configurations. A working memory is also disposed within the housing and is configured to store the set-up configuration in use by the radio receiver.

Abstract: The present invention provides an active capacitor that includes an active all-pass type 90° phase delaying circuit comprising an operational amplifier, a first resistor connected between an inversion input end of the operational amplifier and an input terminal, a second resistor connected between a non-inversion input end of the operational amplifier and the input terminal, a third resistor connected between an output end of the operational amplifier and the non-inversion input end, and a capacitor connected between the non-inversion input end and a ground point; and a fourth resistor having a resistance value sufficiently lower than respective resistance values of the first through third resistors connected between input and output terminals of the active all-pass type 90° phase delaying circuit and an impedance value of the capacitor. Thus, an equivalent capacitor is obtained between the input terminal and the ground point.

Abstract: The present invention provides a receiver input circuit capable of maintaining impedance matching with an antenna feeder wire within all frequency bands to be used and constituting parallel resonant circuits in multi-stage form without using additional circuit portions. The receiver input circuit includes a constant resistance branching filter, a coupling inductor and a tuning circuit. The constant resistance branching filter comprises a low-pass filter and a high-pass filter having termination resistors connected thereto. The low-pass filter and the high-pass filter respectively have equal cut-off frequencies selected to frequencies slightly lower than those lying in a used frequency band and include input ends connected in common to an input terminal of the constant resistance branching filter connected to the antenna feeder wire. The tuning circuit has a parallel resonant circuit constituted of a tuning inductor and a variable capacitance diode.

Abstract: The present invention provides an active inductor that includes an active all-pass type 90° phase advancing circuit comprising an operational amplifier, a first resistor connected between an inversion input end of the operational amplifier and an input terminal, a capacitor connected between a non-inversion input end of the operational amplifier and the input terminal, a second resistor connected between an output end of the operational amplifier and the non-inversion input end, and a third resistor connected between the non-inversion input end and a ground point; and a fourth resistor having a resistance value sufficiently lower than respective resistance values of the first through third resistors connected between input and output terminals of the active all-pass type 90° phase advancing circuit and an impedance value of the capacitor. Thus, an equivalent inductor is obtained between the input terminal and the ground point.

Abstract: The present invention provides a direction finder antenna that includes an antenna mount having one flat portion and four extensible whip antenna elements respectively upright provided rotatably at antenna upright-provided points formed on one circumference at an antenna upright-provided surface. The four extensible whip antenna elements can be rotatably set to arbitrary angular positions lying in sector-shaped areas each having an open angle of 180° orthogonal to the one circumference, which are formed on the antenna upright-provided surface side, centering on the respective antenna upright-provided points at the antenna upright-provided surface.

Abstract: A receiver input circuit comprises an R-? type low-pass filter, a small-capacitance type coupling capacitor element and a parallel tuning circuit. The low-pass filter has an inductor element and a first capacitor element both connected in series, and a shunt-connected second capacitor element. The first and second capacitor elements are equivalent to ones obtained by dividing a normal shunt-connected capacitor element into two. A total capacitance value thereof is selected equal to the capacitance value of the normal shunt-connected capacitor element. The parallel tuning circuit makes use of a tuning first variable capacitance type capacitor element. A second variable capacitance type capacitor element is used for the small-capacitance type coupling capacitor element.

Abstract: In demodulation of a FSK signal, a circuit for detecting a center level of said signal and correcting an error thereof is provided. Said circuit can accomplish the detection of the center level correctly always even if there exist cords with various lengths in a length of “1” or “0” of a synchronizing signal at beginning of communication and during communication, and yet frequency variation happens at that time. Said circuit has sample hold circuits SH1 and SH2 each of which are provided so as to correspond to “1” and “0” of an input demodulated data signal. In said circuit a center level value is an average value of voltages held in said sample hold circuits when said signal changes from “1” to “0” or “0” to “1” and a center level value is obtained by adding or subtracting a voltage of ½ of difference between two hold voltages held in another sample hold circuit SH3 to or from a hold voltage in a receiving side at present time when said signal keeps “1” or “0” continuously.

Abstract: With the objective of providing a scanning receiver capable of capturing a target radio wave in an extremely short period of time by use of a simple constituting means, a plurality of wide frequency division bands in which a full frequency range is divided into predetermined frequency ranges are set and the field intensities of received radio waves are retrieved using the output of an intermediate frequency amplifier circuit over the set wide frequency division bands in order. Further, when a received radio wave having a field intensity greater than or equal to a prescribed level is obtained upon the above retrieval, receive frequencies are swept from one end of each of the wide frequency division bands to the other end thereof. When a target radio wave can be captured upon the above sweeping, transition to the operation of receiving the target radio wave is performed.

Abstract: A variable attenuation circuit comprises a common-base connected transistor, a collector load resistor connected between a collector of the transistor and an AC ground point and having a small resistance value of a few ohms or so, and a bias adjustment resistor connected to the base of the transistor, for adjusting a degree of signal attenuation. An input signal is supplied to an emitter of the transistor and an attenuated output signal is derived from the collector of the transistor.

Abstract: There is provided a negative impedance converter, which has negative impedance conversion function by widening the available range of a generalized impedance converter. A generalized impedance converter is composed of two operational amplifiers Q1 and Q2 and four series-connected first to fifth impedance elements Z1 to Z4. The four impedance elements included in the generalized impedance converter are all set as the same resistor R1, and an impedance element Z6 is connected between the intermediate point B of the series-connected impedance elements and the ground. The magnitude of the impedance element Z6 is set smaller than that of load impedance element Z5. By doing so, the input impedance Z11? becomes negative, and the kind of the impedance is determined depending on the kind of the impedance elements Z5 and Z6.

Abstract: In order to provide a negative resistance circuit which is not influenced by means of change of temperature and source voltage, etc., operates stably and has simple circuit construction, a first stage circuit of the negative resistance circuit is a collector-emitter dividing type amplifying circuit comprising of a npn transistor and a second stage circuit thereof is an emitter earth type amplifying circuit comprising of a pnp transistor. A collector output of the pnp transistor is connected to a base of the npn transistor to constitute a positive feedback path and is divided and is connected to an emitter of the npn transistor to constitute a negative feedback path. An amplification factor A of the emitter earth type amplifying circuit and voltage dividing ratio ? is set to be (1+A?)<A.