Abstract: A means for regulating the power of a fluorescent tube in a vehicle supplied by a DC source by providing the control circuit of an oscillator transistor of an inverter with an adjustable RC circuit. Even very much dimmed tubes can be lighted with the use of a switch by-passing the RC circuit.

Abstract: A pulse transformer is provided for triggering a magnetron in a microwave oven from a low level d.c. control signal. A step-up transformer has a secondary connected to a magnetron triac and a primary connected to a blocking oscillator circuit. The blocking oscillator circuit utilizes a single transistor, at the base of which there is a biasing compacitor. The system is activated by grounding of a control lead in a microprocessor controller for the microwave oven. Grounding of the control lead charges the biasing capacitor until the transistor conducts. Transistor conduction produces a feedback which discharges the capacitor. The circuit electrically isolates the high voltage, high current magnetron power system from the microprocessor controller.

Abstract: A blocking oscillator DC to DC converter includes a first transformer which is charged up and provides feedback to a switching transistor on one half of the cycle and discharges stored energy from the secondary during the second half of the cycle. To reduce switching losses the first transformer driven switching transistor is turned off by a control transistor disposed between the switching transistor base and ground, the control transistor being turned on and off according to the charge on a base capacitor charged by the first transformer. A second transformer may be included to control the power across a gap disposed to kill flying insects.

Abstract: A rotation detecting apparatus detects the angular position of an engine by rotating from the engine an electrically conductive rotating member having a plurality of equally spaced projections and notches formed on the periphery thereof and arranging a detector to face the rotating member and detect its projections and notches. The detector incorporates a self-running blocking oscillator circuit comprising a transformer and a field-effect transistor. With the engine rotating, the oscillator circuit oscillates when one of the notches on the rotating member is opposite to the detector, whereas when one of the projections on the rotating member is opposite to the detector the oscillator circuit does not oscillate due to the eddy current loss caused in the projection. Another circuit is connected to the oscillator circuit, and this circuit generates a pulse signal whose signal level changes in synchronism with a change in the oscillation condition of the oscillator circuit.

Abstract: A DC-DC converter includes a blocking oscillator which is fed with a dc input from an input source and which oscillates to produce an output, which is rectified by a rectifier. The converter also includes an output voltage controlling transistor, the base of which is fed with the rectified output through a constant voltage element. The transistor controls a base current to an oscillating transistor which is contained in the blocking oscillator. The base current to this latter transistor is fed from the input source through a starting resistor and is also fed from the rectifier output through another resistor.

Abstract: A blocking oscillator for driving the armature of a buzzer comprises a transistor which is stabilized against changes in ambient temperature and fluctuations of a supply voltage. A core is provided for magnetically driving the armature, and carries thereon a drive coil which induces a regularly varying electromagnetic field therein as well as a control coil which is connected in feedback relationship with the drive coil. The drive coil forms together with the collector emitter path of the transistor a series circuit, which is connected with a power supply and which is shunted by another series circuit comprising a resistor, the control coil and a diode and which is also connected across the power supply. The base of the transistor is connected with the junction between the resistor and the control coil. The control coil is shunted by a forwardly poled diode.

Abstract: A circuit arrangement for the ungrounded transmission of signals through testing points in communication facilities with the aid of high-frequency oscillations. The high-frequency oscillations are controlled on one side of the testing point and are rectified on the other side of the testing point. The rectified signals are utilized to reproduce the signals again. An oscillator is operated in dependency of the signal polarity by the signals without the requirement of external sources of power.

Abstract: A DC to DC converter with voltage regulator for converting a low level voltage source to a higher level DC, comprising an oscillator circuit with a low resistance starting current path, a rectifier circuit for rectifying the oscillator output, and a regulator for providing a regulated DC output voltage of predetermined level. The oscillator embodies one or more FET devices connected to provide an extremely low DC startup resistance as well as a low cutoff voltage characteristic. With this configuration, the low startup current from the voltage source can initiate switching so that oscillation can occur.

Abstract: A microwave latching ferrite device is provided of the type associated with microwave transmission lines for effecting a phase shift or switching of the microwave signal being propagated. Driving means is provided for a latch winding of the ferrite device in the form of a blocking oscillator coupled between an input and the latch winding. The blocking oscillator includes a power transistor and a toroidal transformer coupled thereto. In response to a trigger pulse on the input, the blocking oscillator generates a single latch pulse on the latch winding, which is effective to change the degree of magnetization of the microwave ferrite device.

Abstract: A photographic flash system in which the storage capacitor for a flash tube is charged only before each flash exposure by a charge control circuit actuated by a pushbutton. The control circuit responds to the discharge of the capacitor through the flash tube to stop the charging process until it is reinitiated by operation of the pushbutton.

Abstract: In a typical self-oscillating, single-ended converter that is pulse width modulated to regulate the output signal, duty cycle changes to stabilize the output signal cause the switching frequency of the converter to vary.The switching frequency of the single-ended converter disclosed herein is stabilized by controlling the on and off durations of the switching device in an inverse proportional relationship to each other. The relation is controlled by adjusting the charging threshold of a timer circuit controlling the conducting interval of the switching devices in response to a voltage regulation error signal which controls the nonconducting interval thus limiting the total period of the switching device to a fixed interval.

Abstract: A high efficiency switching drive for a resonate power transformer having the ability to maintain a constant output voltage over a wide range of source voltage variation while maintaining good power conversion efficiency is provided. A transistorized class-C oscillator has means to saturate the transistors during conduction time to allow the transistor voltage to remain small as opposed to a current source as in the conventional class-C oscillator.

Abstract: A relaxation circuit effects the drive of a blocking invertor for supplying a discharge lamp, thus enabling this invertor to operate in a wide range of the electric input voltage while the whole arrangement has a high efficiency.

Abstract: A high frequency signal for cutting human tissue is generated by common-emitter configured oscillator circuit that is adapted to maintain the cutting signal relatively constant in spite of impedance variations in the load caused by variations in the conduction of the tissue being cut.

Abstract: A pulse discharge electronic control circuit for providing an output signal of predetermined electrical energy and duration for engine ignition, missile firing or the like, the circuit having no moving parts and including means for producing electrical oscillations, means for storing the electrical energy thereof, and means for discharging the stored energy through a load, means also being included for providing high and low voltage output, alternating and regulated current output, and regulated voltage output and for converting alternating to direct current at a higher or lower level than the input signal at a theoretical one hundred percent efficiency.

Abstract: A single pulse blocking converter for generating of a constant output voltage has a switching transistor and a transformer wherein a feedback effect of the transformer supplies the base current of the switching transistor by way of the collector-emitter path of a driving transistor. The driving transistor is controlled by means of a control transistor in dependence upon a measured voltage which is in proportion to the output voltage of the blocking converter. The circuit is particularly characterized in that an auxiliary circuit is provided with a transistor which, during the transition of the switching transistor from the conductive into the blocked condition, applies a blocking voltage to the control path of the switching transistor and in that, by means of a periodic resetting of the auxiliary circuit by the pulses from a pulse generator, the blocking voltage is switched off and a new switching period is initiated for the switching transistor.

Abstract: An electronic circuit including a transistor which is biased to conduction is provided to initiate actuation of an electromagnetic transducer. The transducer has first and second coils one of which actuates the sounder. A potential is induced in the other coil and this induced potential is used to cut off the transistor. The next cycle of operation is initiated when the induced potential falls below a predetermined value in response to the reduction of the magnetic flux which, in turn, was the result of the transistor having been cut off.

Abstract: A high efficiency switching drive for a resonate power transformer having the ability to maintain a constant output voltage over a wide range of source voltage variation while maintaining good power conversion efficiency is provided. A transistorized class-C oscillator has means to saturate the transistors during conduction time to allow the transistor voltage to remain small as opposed to a current source as in the conventional class-C oscillator.