Abstract: A D.C. supply circuit for a television receiver which has a load circuit including at least one controllable semiconductor switch, the supply circuit comprising means for rectifying an alternating mains supply, a smoothing circuit connected between the rectifying means and load circuit and delay means for delaying the application of the full rectified and smoothed voltage to the load circuit when the receiver is initially turned on, wherein the delay means include means for inhibiting a certain number of cycles of the rectified A.C. voltage from being applied to the said smoothing means, so as to provide a D.C. voltage in which the number of cycles inhibited from reaching the smoothing means determines the delay with which the said D.C. voltage reaches the full value at the load circuit.

Abstract: A relatively flat, rectangular, box-shaped, rechargeable, battery pack has a multi-positionable plug with prongs. The plug can be appropriately positioned for recharging the pack by insertion of the plug into either a European-type, deeply recessed receptacle, in a shallow recessed receptacle or in a flush, non-recessed United States-type receptacle. The pack is adapted to interchangeably fit into a pocket or any one of a plurality of pockets in a device in which the pack is to be employed. The prongs on the plug furnish voltage to the device when the pack is in a device pocket and furnish voltage to the pack during recharging. In a discharge mode, the plug is depressed and latched within the battery pack leaving only the prongs external of the battery pack for insertion into the device to be powered. The plug is likewise depressed for recharging in a flush-type receptacle. The pack discharge circuitry is actuated by a mating post in the housing of the device to be powered.

Abstract: A self-powered fiber optic interconnect system in which electrical output from data transmitting equipment is converted in a transmitter unit to optical signals in a fiber optic cable for transmission to a receiver unit for reconversion to electrical signals for data receiving equipment and a power source separate from the transmitting and receiving equipment so that the interconnect system can be completely interchangeable with an electrical copper wire interconnect system. When the data transmitting equipment is a computer with parallel data output, the transmitter unit converts the parallel output to serial data output for transmission to the receiver unit over a single fiber optic cable and the receiver unit reconverts the output to parallel data for the data receiving equipment.

Abstract: A sealed DC power converting station is provided with a bus bar group disposed at the central portion of the station and first and second groups of sealed controlled semiconductor switching units disposed on the opposite sides of the bus bar group. The switching units are respectively connected to the bus bar group through disconnectable gas insulated connection ducts. The station further includes a sealed smoothing reactor connected in series with a DC transmission line and arrestors provided for respective gas insulated connection ducts.

Abstract: A device provided with its own power supply to be hooked up to the lighting system on a vehicle trailer, such as semi-trailers, campers, mobile homes, and the like, for the purpose of flashing all or some trailer lights on and off while the trailer might be left unattended at the side of a road so as to warn passing motorists of its presence. The unit consists of a dry cell battery, a conventional flasher mechanism, an on-off switch, a mounting plate provided integrally with a handle therewith, and a plug adapted to fit a vehicle trailer lighting system. The device is portable and can be easily connected or disconnected to a vehicle trailer so that it can readily be stored in the towing vehicle when not in use or it can be readily relocated from one trailer to another.

Abstract: A power pack for a d.c. energized device, the power pack providing a predetermined d.c. voltage and being of given shape and dimensions, its output terminals having predetermined positions. This power pack includes a casing having the given external shape and dimensions and two output terminals in said predetermined positions. Inside the casing a d.c. power supply is provided adapted to deliver an on-load d.c. voltage lower than the said predetermined d.c. voltage, and a low consumption converter circuit for converting a signal from the d.c. power supply into a d.c. voltage signal of the predetermined value. The signal from the converter circuit is applied across the output terminals.

Abstract: A carrier belt for electrical batteries is usable as a portable current source. The belt has a buckle, a tongue and at least one compartment on the outside thereof for receiving at least one object; the compartment includes a carrier plate attached to the belt, and a protective cover attached to the carrier plate. The carrier plate and the protective cover are made of material which is relatively stiff with respect to the belt.

Abstract: Electromagnetic interference shields are connected to electrical reference points from specially selected null or "center tap" connection points where noise voltages induced in the surface of the electromagnetic shield are substantially balanced out such that injection of such induced interference noise voltages to the connected reference points are substantially reduced. Special selection of isolated reference points for the input and output circuits as well as a special combination of electromagnetic interference shields substantially reduces the electromagnetic interference emanations from an electrical power supply circuit incorporating an inverter and transformer windings therewithin which normally constitute sources of unwanted electromagnetic interference signals unless suppressed.

Abstract: A direct current power supply system for recreational vehicles having an auxiliary chargeable battery wherein a transformer powered converter is utilized to rectify alternating current into direct current, and where the circuitry includes a battery fast charging circuit and control utilizing sensing means for automatically terminating battery fast charging upon predetermined conditions being attained. Fast charging of the battery is accomplished through a converter transformer of economical construction having a variable voltage output controlled in dependence by the fast charging operation.

Abstract: A starting aid and reserve light for vehicles, especially cars. The starting aid comprises at least two identical secondary batteries normally connected in parallel and charged together with the starter battery, when the car is in use. However, a solid state diode prevents the discharge of these batteries together with the starter battery. In case the starter battery is exhausted, being not capable of starting the motor, it can be sufficiently recharged by the starting aid. This is done by means of a switch disconnecting the diode, connecting said secondary batteries in series and simultaneously the resulting double voltage battery in parallel with the starter battery. The starting aid includes a lamp, providing a powerful, portable reserve light.

Abstract: A portable electronic calculator is provided with a housing carrying a first printed circuit board having the operating parts mounted thereon, i.e., keyboard, electronic arithmetic unit, and multi-digit display unit. The housing is of rectangular outline and of shallow height, and is provided at one end with a receptacle communicating with the first printed circuit board and opening at the end of the housing. An electrical supply unit is mounted on a second printed circuit board which slides into said receptacle, said two printed circuit boards having plug-and-socket connection means therebetween for automatically making and breaking connections when said second printed circuit board and electrical supply unit are inserted into or removed from said receptacle.

Abstract: A portable power package has a supporting box provided with a cavity arranged for receiving an electrical battery such as a conventional storage battery. Pairs of jacks and switches are mounted on the box in series with the battery and in parallel with one another for permitting lamps and appropriate appliances to be selectively connected to the battery by means of inserting a plug on the lamp or appliance into a mating jack provided on the box. A charger is arranged in the cavity of the box together with the battery for permitting the battery to be recharged by either a standard AC power source or by another battery, while additional space is provided in the cavity for storing the lamps, and the like, when the latter are not in use.

Abstract: A signal pickup means is provided in a power supply having an inverter driven transformer therewithin for producing a cancellation signal substantially equal in magnitude and opposite in phase with respect to an unwanted common mode interference signal which otherwise appears on the electrical output from the secondary windings of the transformer with respect to an electrically isolated electromagnetic shield about the exterior of the power supply. This signal pickup is connected to the secondary winding and to an electrostatic shield about the secondary winding so as to effectively add the cancellation signal to the interference signal thereby substantially eliminating and reducing the unwanted common mode emanations from the output of the power supply. Preferably, the signal pickup is connected to substantially reduce unwanted common mode potentials between the center tap of the secondary windings and other shielding of the power supply in spite of electrical isolation therebetween.

Abstract: A first power supply and output circuit and a second power supply and output circuit for use with a microphone unit having an electrostatic transducer and pre-amplifier transistor is disclosed. DC power to the microphone unit is supplied from the first circuit through a single core cable. An output signal from the microphone unit also passes through the cable to an output transformer in the first circuit. The first circuit has a first battery and the second circuit a DC power source which, when connected to the first circuit, stops drain on the first battery.

Abstract: A power pack unit includes a casing and cover and a transformer subassembly having a molded bobbin of insulating material which receives primary and secondary lugs, a selected primary and a secondary winding configuration, laminations, A.C. terminals, connecting wiring, and a bobbin-mounted switch. This switch is positionable external of the casing for connecting selected primary or secondary taps as required to accommodate to a particular A.C. supply, i.e., 110 or 220 volt A.C., or to provide a selection of A.C. or D.C. output voltages.