Abstract: A main ladder attenuator has a series of resistors and switches for connecting corresponding resistors to an output. The controller has an auxiliary ladder attenuator connected to the main ladder attenuator in series and having a series of resistors and switches. Each of the resistors of the auxiliary ladder attenuator is provided for interpolating between the adjacent resistors of the main ladder attenuator.

Abstract: A vehicular battery operated charger (202) for charging an electronic device such as a radio (204) includes a controller (218). Controller (218) determines the battery voltage of the vehicles battery (222) and compares it to a threshold level stored in controller (218). Charger (202) will automatically charge radio battery (206) as long as the voltage level of the vehicles battery (222) does not drop below the threshold level stored in controller (218).

Abstract: A power supply includes a main power supply section having power dissipating components therein and a stand-by power supply section. When the main power supply section is off, the stand-by power supply section uses the power dissipating components in the main power supply section to dissipate waste power. When the main power supply section is on, power from a secondary power supply driven by the output from the main power supply section is used to drive the stand-by power supply section thereby reducing any power dissipating requirements of the stand-by power supply section.

Abstract: An output circuit provided with a photo coupler for transmitting a control signal from a control circuit to an output side in an electrically isolated condition, a load driving transistor (15), and a power supply stabilizing circuit (15) for supplying an electric power for driving the load driving transistor (13) from a load side power supply (13). The power supply stabilizing circuit includes a low voltage detection circuit and an input/output short-circuiting circuit, and the input/output short-circuiting circuit is made conductive when an input voltage to the power supply stabilizing circuit is determined to be lower than a predetermined voltage. As a result, even if the load side power supply has a low voltage, it can drive the load driving transistor, and thus the load side power supply can be used over a wide range of voltages.

Abstract: A reference generator includes a first, a second and an additional third current mirror for generating both a reference output current and a reference output voltage. As the reference output voltage only depends on the gate-source voltages of transistors which are fed with a constant current, the reference output voltage has a constant value and is substantially independent of the ambient temperature.

Abstract: A transformerless control circuit turns the motor of a vacuum system ON/OFF using contact points at remote vacuum inlets, the contact points being electrically isolated from the 124/240 A.C. volt power line that supplies power to the vacuum system motor and the control circuit.

Abstract: The battery charging system includes a generator, a rectifier system with main diodes and exciter diodes as well as two terminals (B+, D-) for battery charging, at least one terminal (D+) for consuming points, a voltage regulator (14) for a generator output voltage, a charging control light (16) and a fail-safe device (15) structured to indicate faults and for protection from excess voltages. The fail-safe device includes an additional voltage regulating device (17) connected electrically to the generator and a relay (27) connected with the additional voltage regulating device.

Abstract: An electronic circuit device having a protection circuit for protecting a switching system electronic circuit when a ground terminal is removed from the device. The protection circuit includes a detection circuit for detecting the ground terminal has been removed from ground as a change in an electronic potential of the ground terminal, an input cut-off circuit connected between an input terminal and the electronic circuit to control an operation of the electronic circuit, a low voltage protection circuit for controlling an operation of the electronic circuit in response to an output signal from the detection circuit, and a memory circuit for controlling an operation of the input cut-off circuit in response to both output signals from the detection circuit and the low voltage protection circuit.

Abstract: With respect to their connection to snubber capacitors (C1, C2), a discharge resistor (12) connecting these snubber capacitors, and a link capacitor bank (3), inverter circuits with GTO thyristors (T1, T2) connected in series have parasitic leakage inductances which limit the level of the permissible link direct voltage. In order to reduce the leakage inductances, the snubber capacitors (C1, C2) are surrounded by effectively conducting capacitor covers (17). Sheet-metal shielding covers are fitted over the two ends of the discharge resistor (12). Parallel and series connected capacitors of the link capacitor bank (3) are connected to the positive/negative terminals (23, 24) of the GTO thyristors (T1, T2) in the middle of a heat sink connecting strainer (33), the supply leads being guided essentially parallel and the capacitors being arranged in opposite planes.

Abstract: An electric wall switch has an outer casing on which incoming hot and cold line connectors and outgoing hot and cold load connectors are provided. A ground fault circuit interrupter is connected within the casing between the incoming and outgoing connectors for detecting ground faults and for opening the circuit between the incoming and outgoing connectors on detection of a ground fault. At least one of the outgoing hot load connectors is connected to the ground fault circuit interrupter via a switch for controlling powering of any device connected to that connector.

Abstract: A power supply circuit for a CRT display device includes a low-voltage power supply switching circuit for supplying power to a horizontal oscillation circuit of the CRT display device, and a high-voltage power supply switching circuit for supplying power to high-voltage circuits of the CRT display device. The low-voltage power supply switching circuit includes an oscillator and a switching transistor. The oscillator is triggered by an output of the horizontal oscillation circuit, and the conductive state of the switching transistor is controlled according to an output of the oscillator. The high-voltage power supply switching circuit includes a switching transistor. The conductive state of the switching transistor of the high-voltage power supply switching circuit is controlled according to an output of the low-voltage power supply switching circuit.

Abstract: A grounding system and detection circuit comprising a dual grounding configuration having a first or primary grounding means and a second or default grounding means, and a detection circuit connected to both the first and second grounding means. The first or primary grounding means may be any conventional manual grounding system such as a grounding cable attached to the frame, body, or fuselage of an aircraft, vessel, or vehicle. The second or default grounding means is automatically attached to the aircraft, vessel, or vehicle during fueling or fuel transfer, with the detection circuit positively detecting whether the first or primary grounding means is conductively connected to that same aircraft, vessel, or vehicle. A supplemental detection circuit may be utilized to verify that the first or primary grounding means is connected to the aircraft, vessel, or vehicle prior to connection of the second or default grounding means.

Abstract: The invention relates to a protective plug (1) for connector banks (20) of telecommunication and data systems, comprising a housing (2) for receiving protective elements (7, 8, 9) connected to establish an electrical connection to an earth rail (44) and with a disconnector contact (43) to a bifurcated contact (41) or to circuit tracks (10) provided on a plug tongue, resp. The disconnector contact (43) is provided with terminal contacts (53) for incoming and outgoing cable conductors. In order to provide a protective plug (1) which protects against overvoltages and serves as well as a fuse against overcurrents and for which the outside dimensions allow a close-fit construction of several protective plugs (1), the plug tongue (5) is a printed-circuit board (4, 4a) extending into the housing (2). Two housing compartments (21, 22) are formed inside the housing (2).

Abstract: In an integrated circuit a PNP current mirror can lose its current reflection accuracy when low Beta transistors are involved. Since the conventional PNP transistors can often have low Beta this can become a serious problem particularly with high current gain plural output current mirrors. In the invention a compensation current is fed to the current mirror to increase the PNP transistor base currents as an inverse function of Beta. Several alternative circuit embodiments are also disclosed.

Abstract: A method for detecting full or partial inoperability of a vehicular alternator battery charging system monitors the vehicle's battery voltage and compares it against a controlled reference voltage. When the monitored voltage differs from the target by an amount which is a function of engine rotational speed for a minimum preselected time period, the alternator is disabled and the voltage drop at the battery is monitored to determined whether the alternator is malfunctioning. By observing the voltage drop when the alternator is disabled, the method can distinguish between a charging system problem and a normal state wherein the load exceeds the alternator's maximum output current capacity.

Abstract: A 12-pulse converter of lower rating and minimal current harmonics is obtained with an auto-connected regular hexagon transformer including a delta winding in its center.

Abstract: A duplex receptacle has a housing base with insulating wall elements to which an insulating circuit board supporting a surge supressor circuit is fit. The surge suppressor can be preassembled and located as a compact unit in the housing with connective connections to each of the power conductors and ground. The device also has an insulated ground feature with each ground contact extending into housing base projections which have openings accommodating an insolated ground strap to which the internal ground contacts are joined. The features of the invention are well suited for shallow receptacles as may be fit within outlet boxes of a depth of no more than about 11/2 inches.

Abstract: A reference generator system that operates in either a current-controlled mode or a voltage-controlled mode and includes a power-down circuit connected to the operational amplifier to power down the operational amplifier when the reference generator is switched to the current-controlled mode.

Abstract: For reducing the engineering cost of construction and manufacture for the air gap associated with the second electrode in an overvoltage arrester with air gap connected in parallel, the arrester (22) is enclosed by a cylindrical metal sleeve (28). One edge (19) of this metal sleeve contacts the first electrode (3) of the arrester, while the other edge (14) is laid over inwardly and grips the auxiliary electrode (27) placed on the second electrode (25) with interposition of an insulating disk (26). The outside diameter of this auxiliary electrode (27) is greater than the outside diameter of the second electrode (25). For the centering of the arrester (22) in the metal sleeve (28) the distance between the arrester and the metal sleeve is smaller, at least at three points over the circumference, than the required radial safety distance between the metal sleeve and the second electrode.

Abstract: The circuit switches the power supply of the integrated circuit over to the input voltage of the switching regulator during the initial starting phase, and over to the output of said regulator once the steady state has been reached.