Abstract: In a bearing system for a tone arm for use with a phonograph record player or the like where the bearing system includes a bracket for supporting the tone arm, a rotatable, tubular shaft connected to the bracket for permitting horizontal rotation of the tone arm, and a support for bearing the shaft including ball bearings or the like, the improvement of a suspension wire connected to the bracket at the upper end thereof and extending through the rotatable, tubular shaft; and a device for applying tension to the suspension wire to lessen undesirable movement of the shaft. The tension applying device preferably applies the tension to the suspension wire magnetically and may include a first magnetic structure connected to the lower end of the suspension wire and a second, fixedly positioned magnetic structure spaced from the first magnet structure where at least one of the first and second magnetic structures is a magnet.

Abstract: A phase synchronizer for obtaining a signal which is phase synchronized with respect to another signal which has passed through a transmission system after originating at a signal source, the phase synchronizer comprising a variable phase shifter responsive to the output signal of the signal source for shifting the phase thereof in response to a control signal applied thereto; a phase comparator responsive to the signal which has passed through the transmission system and the output signal of the variable phase shifter to provide an output signal indicative of the phase difference between the two signals applied thereto; a low-pass filter responsive to the phase comparator output signal to provide the control signal for the variable phase shifter so that the phase of the output signal of the variable phase shifter follows the phase of the transmission system output signal.

Abstract: A monostable multivibrator circuit is disclosed. It is characterized by comprising a time constant circuit which includes a capacitor, an amplifier circuit which receives an output signal of the time constant circuit and in which a signal amplifying transistor operates in the non-saturated state, a positive feedback circuit which is connected between the output end of the amplifier circuit and the input end of the time constant circuit and in which a signal amplifying transistor operates in the non-saturated state, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit. Further, it is characterized in that a signal which is produced by the shift from the non-conductive state to the conductive state of the signal amplifying transistor connected to an output terminal of the positive feedback circuit is supplied to the time constant circuit as a positive feedback signal.

Abstract: A monostable multivibrator circuit including a time constant circuit which includes a capacitor, an amplifier circuit which receives an output signal of the time constant circuit, and a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, characterized in that a trigger circuit is incorporated in a part of a circuit loop which is constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit, the trigger circuit comprising an emitter-follower transistor which receives a feedback signal, another emitter-follower transistor which receives a trigger signal and whose emitter is connected to an emitter of the first-mentioned emitter-follower transistor in common, and a constant-current circuit which supplies a constant current to the emitters connected in common.

Abstract: A low pass filter is connected to a junction of a direct-coupled amplifier. The amplifier has a single-ended push-pull output stage consisting of two output transistors and series-connected two resistors. The output transistors are connected to a positive and negative d-c power sources, respectively. The series-connected two resistors are interposed between the two output transistors and defines an intermediate point therebetween at which substantially zero d-c voltage prevails when the amplifier is functioning normally. The junction of the amplifier, to which the low pass filter is connected, is between one of the output transistors and the series-connected resistors. The low pass filter is supplied with the voltage at the junction and applies its output to following isolating means. The means responds to the output of the low pass filter for isolating the intermediate point from a load device connected thereto.

Abstract: The tendency for a sample-and-hold stereo multiplex demodulator having sampling pulses with low duty ratios to deemphasize the high frequency characteristics of the demodulated right and left signals is compensated for by connecting a pair of amplifiers to the right and left outputs and emphasizing the high-frequency characteristics thereof only during stereo reception.

Abstract: This invention discloses a monostable multivibrator which is useful for an FM detector circuit of a pulse count system. The monostable multivibrator has a time constant circuit which includes a capacitor, an amplifier circuit which receives an output of the time constant circuit, a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit; and is characterized in that the amplifier circuit is a differential amplifier which is made up of a pair of transistors connected in the differential form, the transistors being connected in common through emitter resistances connected in series with respective emitters thereof. Thus, the monostable multivibrator can provide pulse signals of a fixed pulse width without being influenced by noise.

Abstract: This invention relates to a monostable multivibrator which is operated in the non-saturated state. The monostable multivibrator circuit includes a time constant circuit which has a capacitor, an amplifier circuit which receives an output signal of the time constant circuit, a positive feedback circuit which is connected between an output end of the amplifier circuit and an input end of the time constant circuit, and a trigger terminal which is disposed in a circuit loop constructed of the time constant circuit, the amplifier circuit and the positive feedback circuit; and it is characterized in that the positive feedback circuit comprises a signal amplifying transistor which has a base receiving an output of the amplifier circuit and a collector supplying a signal to the time constant circuit, and a level clamp circuit which is coupled to the collector of the transistor in order to hold a collector output potential of the transistor higher than a base input potential thereof.

Abstract: A trigger pulse forming circuit for converting a pulse signal into a trigger signal waveform is disclosed. It is characterized in that a time constant circuit is comprised in a collector output circuit of one of a pair of transistors for differential amplification and that a clamp circuit which employs a diode of the base-emitter path of a transistor is inserted between collector output circuits of the transistors for differential amplification. The input pulse signal to be subjected to the waveform conversion is impressed across the bases of the transistors for differential amplification, and the trigger pulse output signal is derived from the collector of the other of the transistors for differential amplification.

Abstract: In a communication receiver, a first mixing circuit, a first band-pass filter responsive to the output of the first mixing circuit, a second mixing circuit responsive to the output of the first band-pass filter, a second band-pass filter with a different center frequency from that of the first band-pass filter responsive to the output of the second mixing circuit, a first local oscillator, the output of which is applied to the first mixing circuit and a second local oscillator, the output of which is applied to the second mixing circuit. Various kinds of interference signals are eliminated by changing the output frequencies of the first and second local oscillators to thereby vary the effective bandwidth and center frequency of the signals which can pass through the receiver and thus eliminate interference. In addition, a third mixing circuit is responsive to the output of the second band-pass filter.

Abstract: A tone control circuit including an operational amplifier having (a) an input circuit or output circuit and (b) a feedback circuit where circuits (a) and (b) are symmetrically disposed with respect to a reference potential such as ground. Circuitry is also provided to compensate for load and/or feedback impedances. Further, circuitry is provided to reduce the number of switches and capacitors needed to vary the high and low cut-off frequencies of the tone control circuit.

Abstract: A local oscillator having a variable frequency oscillator and a carrier frequency oscillator for use in communication systems that transmit and/or receive signals on multiple frequency bands, one crystal reference oscillator; a converter circuit for mixing the outputs of at least the variable frequency oscillator and the carrier frequency oscillator to produce an output having a frequency corresponding to the receiving frequency and a phase-locked loop circuit including a plurality of voltage control oscillators corresponding to the number of receiving frequency bands; a mixing circuit for mixing the output of a predetermined one of the voltage control oscillators corresponding to a predetermined one of the frequency bands with the output of the converter circuit to produce an output of fixed frequency corresponding to the one frequency band; a programmable counter that divides the output of the mixing circuit in accordance with a frequency dividing ratio corresponding to the one frequency band; and a phase c

Abstract: In a monostable multivibrator including a gate circuit having first and second inputs, a differentiating circuit responsive to the output of the gate circuit and a voltage comparison circuit responsive to the output of the differentiating circuit where the gate circuit is adapted to have a trigger pulse applied to the first input thereof and the output of the voltage comparison circuit fed back to the second input thereof, the improvement in the monostable multivibrator of means for setting the reference level of the trigger pulse at the first input lower than the reference level of the output of the voltage comparison circuit fed back to the second input of the gate circuit.

Abstract: In a monostable multivibrator including a gate circuit having at least two inputs where an input signal is applied to a first one of the two inputs and a feedback signal to the other input, a differentiator circuit responsive to the output from the gate circuit, a differential inverter including a current switching circuit where an output load is connected to the collector of the output transistor for deriving an output signal, the improvement comprising an AC grounded base transistor connected in series between the collector of the second transistor and the output load.Even when a low-pass filter is connected to the output load of the above multivibrator, the output signal thereof is stabilized which is important when the multivibrator is used in combination with a low-pass filter in an FM receiver pulse count demodulating circuit.

Abstract: A double super heterodyne FM receiver having a first local oscillator for deriving a first intermediate frequency signal from an FM input signal, tuning means for varying the frequency of the first local oscillator to tune the FM receiver to a predetermined frequency, a second local oscillator for deriving a second intermediate frequency signal from the first intermediate frequency signal, an FM detector for demodulating the second intermediate frequency and means for processing the demodulated signal, means for deriving the direct current component of an output signal occurring at a point after the FM detector, first control means for controlling the frequency of the second oscillator in response to the direct current component so that the direct current component is reduced to substantially zero to thereby lessen shock noise during the tuning of the receiver, second control means responsive to the tuning means being operated to tune the FM receiver so that the control means controls the means for deriving t

Abstract: A double superheterodyne receiver comprising a first mixer responsive to a frequency modulated signal and a first local oscillator signal for providing a first intermediate frequency signal having a frequency f.sub.1 and a positive side frequency deviation of +.DELTA.f.sub.1 and a negative side frequency deviation of -.DELTA.f.sub.2 where .DELTA.f.sub.1 =.DELTA.f.sub.2, a second mixer responsive to the first intermediate frequency signal and a second local oscillator signal having a frequency f.sub.s for providing a second intermediate frequency signal having a frequency of f.sub.2 and harmonics nf.sub.2 and (n+1)f.sub.2 where n is positive integer indicating the harmonic of f.sub.2 in the lower side of f.sub.1 which substantially deviates to f.sub.1 +.DELTA.f.sub.1 or to f.sub.1 -.DELTA.f.sub.2 and n+1 indicates the harmonic of f.sub.2 in the upper side of f.sub.1 which substantially deviates to f.sub.1 -.DELTA.f.sub.2 (when nf.sub.2 substantially deviates to f.sub.1 +.DELTA.f.sub.1) or to f.sub.1 +.DELTA.f.

Abstract: A drive circuit for an electrostatic deflection type cathode-ray tube where the drive circuit includes an amplifier and a load. At least one diode is connected between the output of the amplifier and the load and at least one push-pull emitter follower circuit is provided, the bases of whose transistors are connected to opposite terminals of the diode, the cathode-ray tube being deflected by the output of the push-pull emitter follower circuit.

Abstract: A logarithmic amplifier comprising a common-emitter type transistor amplifier circuit with an emitter resistor and a collector load. A bias voltage is applied to the base of the transistor through a diode so that the overall input-output transfer characteristic of the amplifier exhibits a logarithmic characteristic for a relatively wide range of input signals. A cascade connection of several of the basic amplifier circuits enlarges the dynamic range over which a logarithmic transfer characteristic is achieved.

Abstract: A monostable multivibrator including a gate circuit, a time constant circuit, and an inverter circuit. An input signal to the gate circuit causes the time constant circuit which preferably includes a resistor and a capacitor to charge or discharge. A signal derived from the time constant circuit is applied to an input bias circuit including an emitter follower type transistor circuit associated with a differential amplifier within the inverter circuit to control the duration of the monostable output pulse.

Abstract: A digital frequency display device for digitally displaying the operating frequency of a communication apparatus comprising a reference frequency oscillator, a first frequency mixer for mixing the output frequencies of a first oscillator of the communication apparatus and of the reference frequency oscillator, a second frequency mixer for mixing the output frequency of a second oscillator of the communication apparatus and the resultant frequency provided from the first frequency mixer to produce the display frequency shifted by the reference frequency, and a frequency counter for counting the output frequency from the second frequency mixer and for correcting the shifted frequency component to display the correct frequency.