Abstract: A power control circuit is disclosed which may comprise a transformer having a primary winding and at least one secondary winding, a first and a second series circuit, and a rectifier circuit. The first series circuit may include a first DC power source, a first transistor and the primary winding of the transformer. The second series circuit may include the primary winding of the transformer, an excitation coil arranged to flow through the primary winding of the transformer a current which increases with time, a second DC power source and a second transistor. The rectifier circuit may be connected with the secondary winding of the transformer. In this power control circuit, an excitation current is first caused to flow through the primary winding of the transformer so that energy is stored therein.

Abstract: A switching regulator which is designed so that a negative feedback is applied to the base of a transistor constituting an oscillator adapted for chopping a DC voltage, only during a period of time which is required to effect pulse width control when the transistor is switched from conduction to non-conduction. A control circuit may also be provided which is arranged to compare the output of a current detecting circuit for detecting a current proportional to a current for driving a transformer with the output of an error voltage amplifier for amplifying an output resulting from comparison of a rectified version of the AC output of the transformer with a reference voltage. The foregoing control circuit is also arranged so that when the output of the current detecting circuit exceeds the output of the error voltage amplifier, a trigger signal is imparted to cause the oscillator to be changed from the on state to the off state.

Abstract: A switching regulator in which an input DC voltage is chopped and then applied to drive a transformer from which an AC voltage is derived which in turn is rectified in a rectifier circuit, and the output of the rectifier circuit is compared with a first reference voltage so that an output is provided which corresponds to the difference between the two voltages compared with each other and which causes a current to be charged at a capacitor incorporated in a charge-discharge circuit which is arranged to vary the charged current, and the output of the charge-discharge circuit is compared with a second reference voltage so that a trigger signal is produced and applied to the base of a switching transistor only when the output of the charge-discharge circuit exceeds the second reference voltage.

Abstract: A plurality of flip-flops in cascade are divided into first and second groups. A first gate detects all of the first group assuming a logic 1 to set an RS flip-flop which in turn presets the first group. A second gate changes its logic output when the second groups takes a predetermined logic state after the detection by the first gate. A D type flip-flop, upon simultaneously receiving both an input pulse and the changed output of the second gate, produces an output which presets the second group and resets the RS flip-flop.

Abstract: A switching regulator in which a DC input voltage is chopped by an oscillator applied to a transformer the output of which in turn is rectified by a rectifier circuit; a DC voltage derived from the rectifier is compared with a reference voltage so that a voltage is produced which corresponds to the deviation from said reference voltage of the aforementioned DC voltage derived from the rectifier; the voltage thus produced is amplified by means of an error amplifier; a current proportional to the transformer driving current provided by the oscillator is detected by a current detector; and the output of the error amplifier is compared with the output of the current detector so that only when the former exceeds the latter, a trigger signal is applied to the oscillator, whereby the oscillation of the oscillator is changed from an ON state to an OFF state.

Abstract: A semiconductor device and a method of manufacturing the same, wherein there are provided, on a semiconductor substrate of a first conductivity type, a first and a second epitaxial layer each having a second conductivity type opposite to the first conductivity type. A plurality of regions are defined in the entire area of the epitaxial layer by being isolated by means of an isolation layer of the first conductivity type which extends from the surface of the second epitaxial layer to the semiconductor substrate. Furthermore, a first buried layer of the second conductivity type is formed in each of the isolated regions in such a manner as to extend in the first epitaxial layer and semiconductor substrate so that a transistor can be formed on each first buried layer.

Abstract: An elastic surface wave device including interdigital finger electrodes comprising interdigital fingers each of which consists of a pair of divided finger elements having an equal width. The spacing between adjacent ones of the interdigital fingers is equal to the spacing between the pair of divided finger elements thereof. Importantly, at least one of the interdigital fingers is differentiated from the remainder of the interdigital fingers in respect of the distance from the center of the spacing between one of the interdigital fingers and that one of the interdigital fingers which is adjacent thereto on one side to the center of the spacing between the aforementioned one interdigital finger and that one of the interdigital fingers which is adjacent thereto on the other side. Furthermore, the interdigital finger electrode is designed such that the width of the respective finger elements is equal to the spacing therebetween.

Abstract: A control circuit of an FM stereophonic receiver includes two sets of symmetrically arranged transistor pairs which form a DC supply regulating circuit therein and are connected to respective constant current sources. The control circuit receives an output signal from an FM detector and controls the coupling of the FM detector output to different input terminals of a switching circuit of the FM demodulator in response to a DC control signal indicative of the level of a received broadcast signal. The switching circuit receives a train of switching pulses of 38 kHz as a switching signal to derive a stereophonic or monophonic audio signal from the controllably applied FM detector output. The DC supply regulating circuit serves to maintain the DC level applied to the input terminals of the switching circuit at a constant value at all times to reduce noise which might occur in the reproduced audio signal when the receiver is switched over between the stereophonic and monophonic modes.

Abstract: An external core member is mounted on a dielectric substrate. The external core member is made of a magnetic material and is formed with a through bore. A coil member is disposed on the substrate and within the through bore. An elastic material casting is formed in the through bore and about the coil member, and having a core receiving bore formed therein. The core receiving bore is arranged coaxially with the longitudinal axis of the coil member so as to extend through the coil member at its center portion. A movable core of a magnetic material is movably retained in the core receiving bore.

Abstract: In a method of fabricating a piezoelectric thin film of zinc oxide by means of a sputtering process, zinc and alkaline earth metal are sputtered together in an oxygen atmosphere to thereby produce zinc oxide containing the alkaline earth metal.

Abstract: In a stabilized power supply circuit including a feedback circuit, wherein there alternately occur a time during which a current is caused to flow in a transformer so that energy is stored therein and a time during which the energy stored in the transformer is discharged, there is provided a compensation winding adapted to produce an induced voltage in accordance with an input voltage variation. The induced voltage is employed to correct an output voltage variation which is caused by the operating resistance of the feedback circuit for the time during which energy is stored in the transformer. The feedback circuit may be constituted at least by a Zener diode, control transistor and switching transistor, and the emitter of the control transistor may be grounded through the compensation winding. Thus the stability of the output voltage with respect to input voltage variations can be greatly improved. The compensation winding may be provided at any desired position in the feedback circuit.

Abstract: Piezoelectric ceramics are provided consisting of a ternary system composition of PbTiO.sub.3 -PbZrO.sub.3 -La(Mn.sub.1-4.alpha. Ni.sub.3.alpha. W.sub..alpha.)O.sub.3 where .alpha. is in the range of 3/40.ltoreq..alpha..ltoreq.1/4.

Abstract: A power control circuit which includes at least one DC power source; and at least one transformer including an excitation winding, a primary winding and a secondary winding; at least two transistors; and at least two diodes. In this circuit, a current increasing with time is caused to flow through the primary winding after energy has been accumulated in the excitation winding. Furthermore, a current induced in the secondary winding by the current of the primary winding and a current resulting from the energy of the excitation winding are superimposed upon each other, and the current resulting from such superimposition is rectified so that there is provided a continuous output.

Abstract: A muting range setting circuit for an FM receiver uses a pair of differential amplifiers. Each of the differential amplifiers employs the same transistors having like polarity with common input and output terminals. The output of the tuner AFC is compared with an input reference voltage in the differential amplifier circuit and the output representing the frequency deviation of the FM detecting circuit is applied to the gate driving circuit for control of the muting operation.

Abstract: In a noise cancelling system for FM receivers, means is provided whereby a pilot signal of 19 KHz is always detected from a stereo composite signal, whether or not a noise canceller circuit is operated. The 19 KHz pilot signal is injected into a phase locked loop, and a signal of 38 KHz in synchronism with the 19 KHz pilot signal is generated which in turn is injected into the multiplex demodulation circuit. Furthermore, means may also be provided which eliminates, from the 19 KHz pilot signal, noise mixed into the stereo composite signal and having a frequency characteristic of (19/n) KHz (n=1, 2, . . .) and then detects the foregoing pilot signal, thereby achieving satisfactory stereophonic separation.

Abstract: A flyback type switching power source device alternately having a time during which energy is stored in a transformer and a time during which the stored energy is taken out. A current flowing into the primary winding of the transformer or out of the secondary winding thereof is detected, and the current thus detected is converted into a DC voltage proportional to the magnitude thereof. Furthermore, a voltage resulting from superimposition of the DC voltage upon a reference voltage is compared with a DC voltage resulting from conversion of a voltage induced in a tertiary winding of the transformer during the time for taking out the energy stored in the transformer to control the time during which energy is stored in the transformer.

Abstract: A surface elastic wave device comprising a substrate of an insulating material, a thin film of a piezoelectric material provided on said substrate, input transducer means for transmitting surface elastic wave, and output transducer means for receiving the surface elastic wave. At least one of the input and output transducer means includes a comb-like electrode which comprises interdigital fingers, and a plurality of electrodes which extend across the interdigital fingers in opposing relationship with the comb-like electrode, with the thin film being interposed between the plurality of electrodes and the comb-like electrode. The output transducer means may be arranged to receive or eliminate only surface elastic wave which is permitted to propagate in a direction which is different from that perpendicular to the longitudinal direction of the aforementioned interdigital fingers.

Abstract: A surface elastic wave device including input and output transducer means provided on a base plate of a piezoelectric material, wherein the input transducer means or output transducer means or both comprise a plurality of comb-like electrodes each including an equal number of pairs of interdigital electrodes, and the comb-like electrodes are arranged in parallel with each other with a predetermined spacing therebetween in the longitudinal direction of the interdigital fingers and with a predetermined width. Some of the comb-like electrodes may be differentiated from the remaining ones in respect of the spacing in the longitudinal direction of the interdigital fingers, the width, the number of interdigital finger pairs and/or the overlapping length of the interdigital fingers.

Abstract: A trapped energy type of piezoelectric filter includes a polarized ceramic wafer 9, input and output electrodes 11, 13 secured to one major surface of the wafer and spaced from each other by a constant width gap, and a ground electrode 15 secured to the opposite major surface underlying the input and output electrodes. The configuration of the ground electrode is made symmetrically concave or convex about its longitudinal axis in varying degrees to thereby control the band pass width, the symmetry of the filter characteristic about a center frequency, and eliminate peak ripples.

Abstract: A helical resonator filter is disclosed which comprises helical coils wound on hollow bobbins respectively, and magnetic cores adjustably inserted in the hollow bobbins respectively, the helical coils being electromagnetically coupled to each other via the magnetic cores. The hollow bobbins are accommodated in a metal casing which is provided with no inside partition wall formed with a window adapted for enabling the coils to be electromagnetically coupled to each other. Thus, the characteristic of the helical resonator filter can be controlled as desired, simply by adjusting the length of that portion of each magnetic core which is inserted in or overlapped by each helical coil.