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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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Brushless dc motor operates as a commutator in a vacuum environment with high efficiency and long life. Because of its excellent response time, it can be used in the servomechanism field.
Full-wave bridge rectifier circuit controls the direction, speed, and braking of a dc motor. Gating in the circuit of Silicon Controlled Rectifiers /SCRS/ controls output polarity and braking is provided by an SCR that is gated to short circuit the reverse voltage generated by reversal of motor rotation.
Electronic circuit used relay coil to sense and control dc voltage. The control relay is driven by a switching transistor that is biased to cutoff for all input up to slightly less than the threshold level.
Design of medium power dc to 115 volt, 60 Hertz ac inverter
Low-voltage, high current dc-ac converter from magnetoresistor, superconductor, Hall effect, or thin-film devices
Thin film deposition on metal oxide semiconductor devices, and dc to ac conversion methods
Precision dc potentiometer microwave insertion loss test set for calibrating low noise microwave receiving systems used in space communications
Two way, latching, dc solenoid valve to isolate reaction control engine clusters from main hypergolic propellant supply system
Dual-channel microwave insertion loss test set which incorporates power meter coaxial thermistors with dc nulling scheme
Attitude control by means of reaction wheel driven by photoelectronically commutated DC torquer
Electronically switched DC motor commutated by light beam directed onto photodiodes
Precision DC potentiometer microwave test set for coaxial or waveguide insertion loss measurement
Helium atoms in 2P level contribute to formation of excited helium molecules in positive column of DC discharge, noting IR portion of pumping radiation is responsible for enhancement of molecular population
Precision DC potentiometer test for measuring microwave coaxial or waveguide insertion loss
Design and fabrication of high reliability differential dc amplifier for Saturn hydraulic engine control
Thermistor mount for dc potentiometer insertion loss test set
Anatomy and dc characteristics of arterial system, and pulsating flow /ac/ characteristics
Basic circuitry for microminiature dc integrated- circuit, direct-coupled, signal-conditioning amplifier