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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Balanced bridge circuit, supplied with low-voltage direct current and connected to a readout device, measures remaining brush material, rate of brush wear, armature runout, and brush signature.
Pulse-width-modulated controller, for vehicle electrically driven by direct current from storage battery and requiring highest possible efficiency in battery use, varies electrical power through silicon controlled rectifiers for permanent magnet dc motors. System is not restricted to dc motors.
Calculated surges in switching circuit of pulsed control system direct current electric motor
Direct current power supply for gaseous discharge lamps
High voltage insulators for direct current in acceleration system of electrostatic thrustor
Direct current motor with magnetically suspended rotor
Direct current electromotive system for regenerative braking of electric motor
Reversible current directing circuitry for reversible motor control
Direct current powered self repeating plasma accelerator with interconnected annular and linear discharge channels
Development of apparatus for amplitude modulation of diode laser by periodic discharge of direct current power supply
Low frequency oscillation measurements on spherical magnetized cold cathode direct current discharge by plasma probes
Direct current motor with magnetically suspended rotor for attitude control
Development and characteristics of solid state acoustic variable time delay line using direct current voltage and radio frequency pulses
Ion migration direction in thin Ag, Cu and Au films under direct current effect from resistance radioactive tracer measurements and scanning electron micrographs
The theory, applications, and possible structural designs of capacitive transducers are presented. Emphasis is placed on the circuits used in connection with the sensors, such as AM, FM, resonant circuits, mode circuits, direct current circuits, and special circuits. Some criteria for selection of a design or the purchase of a commercial device are given.
Operating and maintenance instructions for cathodic protection of communication cables at the Cape Kennedy Launch Complex are presented. The system is designed to prevent or arrest corrosion of communication cables buried in soil or submerged in water by impressing sufficient direct current from the rectifier through the anodes to the cable. This process neutralizes or counteracts current flowing from the cable into the soil or water, thus preventing or arresting corrosion of the cable sheath material.
The development of magnetic bearings for use in direct current electric motors is discussed. The characteristics of the magnets used in the construction of the bearings are described. A magnetic bearing using steel armoring on permanent magnets was selected for performance tests. The specifications of the motor are presented. The test equipment used in the evaluation is described.
The method and equipment used for sputtering by use of an apertured electrode and a pulsed substrate bias are discussed. The technique combines the advantages of ion plating with the versatility of a radio frequency sputtered source. Electroplating is accomplished by passing a pulsed high voltage direct current to the article being plated during radio frequency sputtering.