Abstract: A piezoelectric resonator is formed with a case and a stem for housing the piezoelectric vibrating portion thereof. The case and stem are coupled by press-fitting and the interface is coated with a high temperature solder containing at least 90% lead. An inner lead of the resonator is also coated with the solder and a portion of the vibrator is fixed to the lead by melting the solder. Alternative constructions employ a resin case or a metallic plate case and a configuration in which an integrated circuit and a piezoelectric vibrator are integrally molded to achieve a highly desirable mounting configuration.

Abstract: A phase-locked loop circuit has a ring oscillator comprising a plurality of 1st, 2nd, . . . , nth inverter chains composed of series-connected 21, 22, . . . , 2n inverters (n.gtoreq.2), respectively, an (n+1)th inverter chain composed of an odd number of series-connected inverters, and a plurality of 1st-nth selectors associated with the 1st-nth inverter chains, respectively, for selectively outputting input signals to and output signals from the 1st-nth inverter chains, the 1st-nth inverter chains being combined respectively with the 1st-nth selectors in respective combinations, the combinations and the (n+1)th inverter chain being connected in a ring configuration. A phase comparator compares an input clock signal and an oscillated clock signal from the ring oscillator in phase, and applies an output signal to a control circuit which controls the 1st-nth selectors to synchronize the oscillated clock signal with the input clock signal.

Abstract: A direct digital frequency synthesizer employs residue number system based processors to generate output waveforms of desired frequencies. The frequency synthesizer includes a phase accumulator comprising a plurality of individual adders, each adding a predefined quantity to a digit of a frequency setting word in which the individual digits are residue digits of differing moduli. The outputs of the independent adders form a combined residue output word which is used to address a memory storing signal samples. In one embodiment of the invention, the memory is a dual port ROM storing samples of one-quarter of a sine wave and the dual port ROM is simultaneously addressed to read a selected sample and an associated sample corresponding to the magnitude of a sample of the sine wave advanced by 90.degree. from the first sample.

Abstract: A piezoelectric resonator is formed with a case and a stem for housing the piezoelectric vibrating portion thereof. The case and stem are coupled by press-fitting and the interface is coated with a high temperature solder containing at least 90% lead. An inner lead of the resonator is also coated with the solder and a portion of the vibrator is fixed to the lead by melting the solder. Alternative constructions employ a resin case or a metallic plate case and a configuration in which an integrated circuit and a piezoelectric vibrator are integrally molded to achieve a highly desirable mounting configuration.

Abstract: A battery-powered magnetic pen has an oscillator for generating a magnetic field at a contact frequency and a proximity frequency. The oscillator is connected to a resettable timer. The pen also includes a tip switch that is actuated in response to the pen being brought into engagement with an object and disengaged from the object. The tip switch is connected to a pulse generator and to the oscillator. Each time the pen is brought into engagement with an object, the pulse generator resets the timer to initiate the timing of a time out period. Assuming the oscillator is off, the first time the pen contacts an object, the resetting causes the oscillator to be turned on. So long as the oscillator is on, the opening and closing of the tip switch causes the oscillator to switch between the contact frequency and the proximity frequency. Should the timer reach the end of a predetermined time out period, the oscillator is shut off.

Abstract: An optical oscillator uses a monochromatic light beam passing through a poelectric crystal subjected to acoustic vibrations which cause the emission of a diffracted light beam. The undiffracted beam is detected by photodetecting means and generates a first voltage signal. The diffracted beam is passed through a unit for delaying the passage of the beam, e.g. a fiber optics loop, and detected by photodetecting means to generate a second voltage signal. The signals are combined and fed to a control unit which allows a radio frequency signal to reach the piezoelectric crystal, causing acoustic vibrations. The time delay and voltage output relationships in the loop associated with the diffracted beam cause oscillation and control the frequency of such oscillations. The oscillations can be amplitude and frequency modulated by variation of appropriate circuit parameters.

Abstract: A microwave oscillation circuit unit to be installed on one surface of a chassis base having a circuit substrate on its other surface. The unit is provided with at least two screws, and a power supply terminal and an output terminal on its one surface confronting the chassis base when installed on the chassis base. In such a structure, a first nut is threaded on one of the screws which is positioned adjacent to the power supply terminal and the output terminal so that torque caused by tightening the first nut to such one of the screws may act upon the chassis base, the first nut being clear from the circuit substrate. Furthermore, a second nut is threaded on the other of the screws which is positioned apart from both the terminals so that torque caused by tightening the second nut to the other of the screws acts upon both the chassis base and the circuit substrate.

Abstract: A superconducting reversible variable inductor of this invention comprises: a core made of a Type II superconductor having a reversible magnetic permeability variation range in which the magnetic permeability varies reversibly with respect to a variation of a magnetic field of a predetermined strength or less and falling in the range of from a lower critical magnetic field or more to an upper critical magnetic field or less; and one or more coils wound around the core. The superconductor reversible variable inductor has good linear controllability and high speed response of the inductance.

Abstract: A piezo-oscillator includes a semiconductor element having at least an oscillating circuit. A piezo-vibrator having leads extending therefrom is connected to the semiconductor element by a plurality of lead terminals. The semiconductor, vibrator and lead terminals are contained within a unitary resin package.

Abstract: A quartz crystal oscillator having a resonator leaf with electrode film for electrical conduction. The oscillator includes a semiconductor element which oscillates the resonator leaf. Lead terminals have a first end which are integrally molded to the semiconductor element by a resin and second ends which support the resonator leaf.

Abstract: An ultrasonic oscillator device which has automatic gain control and which comprises a phase detector for detecting the phase difference between a load voltage and varying quantities indicating an operational condition of the load. The device further comprises a voltage control oscillator adapted to control an oscillating frequency through a direct current voltage corresponding to the phase difference. Further, the ultrasonic oscillator device is combined with a vibrator driven thereby and a small sized motor having a fan to forcedly cool the vibrator. The vibrator and the fan are accommodated in a housing, the size of which is made small, to produce a compact type machine.