Abstract: A transformer with an electrostatic shield body between its primary and secondary windings, one end of the shield body being connected to a zero potential point of the primary side from the AC standpoint. This reduces the capacity coupling between the primary and secondary windings. This transformer is particularly useful with an inverter.The transformer may include primary and secondary windings, each having a pair of terminals, and a magnetic core provided in connection with the primary and secondary windings magnetically. First and second static shield bodies may be provided at each side of the primary and secondary windings and therebetween, and these first and second static shield bodies are electrically connected to one terminal of the primary and secondary windings, respectively, so as to reduce the capacitance therebetween.

Abstract: A starting circuit for an inverter includes, at least, a control winding provided in connection with a saturable magnetic core of an input transformer of the inverter, a transistor and a capacitor. When a DC voltage source is activated, a discharge current of the capacitor flows through the collector-emitter circuit of the transistor and the control winding so as to start the switching operation of the inverter. A control circuit is provided for detecting a secondary voltage of the inverter so as to cut off the operation of the starting circuit after the inverter starts.

Abstract: A monostable multivibrator having a novel four terminal semiconductor device with a generally V-shaped emitter grounded current amplification characteristic. Means are provided to bias the operation of the device to a low point on the characteristic, to provide a trigger signal to the base of the semiconductor device for placing the device in a conducting state and, through the operation of a capacitor coupled between the gate and collector terminals, to shift the operation of the device to a high level on the emitter-grounded current amplification characteristic thereby sharply decreasing the output voltage obtained at the collector. Discharge circuit means are provided for the capacitor to gradually reduce the gate voltage and to shift the operation of the device back to the low circuit point thereby reducing the collector current and suddenly increasing the collector voltage.

Abstract: A transistor inverter includes at least a pair of switching transistors, a transformer with primary and secondary windings, a DC voltage source with a pair of output terminals and a voltage reference terminal, and a rectifying circuit connected to the secondary winding of the transformer. A collector electrode of one of the switching transistors is insulated from a chassis by an insulation means comprising a first insulating layer, a conductive layer such as a heat sink and a second insulating layer. The conductive layer is electrically connected to the voltage reference terminal of the DC voltage source so as not to produce an undesirable radiation through the chassis.

Abstract: A transistor amplifier comprised of a class-A amplifier connected in cascade with a push-pull amplifier. The class-A amplifier includes first and second field effect transistors having triode-type dynamic characteristics with their respective gate electrodes connected to receive an input signal and their source and drain electrodes connected in series across opposite power supply terminals. The push-pull amplifier includes third and fourth field effect transistors having triode-type dynamic characteristics with their respective gate electrodes connected to the first and second field effect transistors and their source and drain electrodes connected in series across the opposite power supply terminals.

Abstract: A transistor inverter includes a pair of switching transistors each having base, emitter and collector electrodes, each of the collector and emitter circuits of which is connected between a DC voltage source through a primary winding of an output transformer, respectively, the secondary winding of which is connected to a rectifying circuit so as to produce a DC output voltage at its output. The transistor inverter also includes an input transformer with a saturable core and voltage feedback and current feedback circuits. The current feedback circuit has another transformer which controls the amount of current feedback, and the winding ratio of the primary and secondary windings is determined in connection with the current amplification factor of said first and second switching transistors in order to improve a switching speed of the switching transistors.

Abstract: A pulse width modulated signal amplifier includes a first input terminal supplied with a rectangular wave signal as a carrier, a second input terminal supplied with a modulating signal, such as an audio signal, an integrator supplied with both the rectangular wave signal and the modulating signal, a high gain amplifier receiving the output of the integrator, a low pass filter receiving the output of the high gain amplifier and producing a demodulated signal corresponding to the modulating signal and which is supplied to an output terminal, and a negative feedback circuit connected between the output of the high gain amplifier and the input of the integrator.

Abstract: An amplifier having ready application as an amplifier for pulse width modulated signals, is comprised of first and second field effect transistor devices which exhibit triode-type dynamic characteristics. These field effect transistor devices are connected in push-pull amplifying relation for receiving a signal to be amplified and for supplying an amplified signal to a load. A low-pass filter device connects the load to the push-pull field effect transistor devices. The output terminals of the field effect transistor devices are connected in series across a voltage supply which is used to supply the energizing voltages to the transistor devices.

Abstract: A pulse width modulated signal amplifier includes a pair of transistors, each having a base, an emitter, and a collector. The bases are supplied with a pulse width modulated signal to be amplified, and the emitters are connected to each other and to an output terminal. A low pass filter connects the output terminal to a load. The collectors are connected to first and second terminals of a DC power source through first and second DC voltage sources, respectively, and first and second diodes are connected between the connection point of the emitters and corresponding terminals of the DC power source, respectively. First and second voltage limiting circuits are provided between the bases of the first and second transistors and corresponding terminals of the DC power source so as not to produce a longitudinal amplitude distortion in response to the switching operation of the first and second transistors.

Abstract: A transistor amplifier comprising a bipolar transistor having an input electrode and a pair of output electrodes, one of the output electrodes being coupled to the gate electrode of a field effect transistor, the field effect transistor having triode-type dynamic characteristics. Respective sources of operating potential are coupled to the bipolar and field effect transistors. To stabilize the DC bias current flowing through the field effect transistor in the event of fluctuations of the operating potential supplied thereto, a portion of such fluctuations is injected into the other output electrode of the bipolar transistor. The field effect transistor is adapted to drive a load impedance.

Abstract: A transistor amplifier comprised of a transistor supplied with a first operating voltage and a field effect transistor having triode-type dynamic characteristics and supplied with a second operating voltage. The gate electrode of the field effect transistor is coupled to the transistor collector. In order to stabilize the field effect transistor bias current in the event of fluctuations in the second operating voltage, a voltage control circuit is responsive to such fluctuations to alter the first operating voltage so as to vary the gate voltage applied to the field effect transistor in a direction to stabilize the bias current.