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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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Two techniques have been conceptually proposed as possible means of reducing parasitic beta in lateral p-n-p transistors. One method uses a degenerate substrate and high concentration P /plus/ guard-ring diffusion, another places the base contact at the center of an annular ring structure.
Low insertion-loss C band parasitic probe couples RF energy from a transmitting medium to a receiving medium with a minimum of interference in order to minimize power requirements.
Design, manufacture, and testing of parasitic load resistors for Brayton power conversion system
Adhesion in air and vacuum of titanate coatings applied to 321-stainless steel Brayton parasitic load resistors
Parasitic load speed control for dynamic space power systems
Multiple phase-controlled parasitic load effects on turboalternator output speed control
Reduction of alternator apparent power requirements and harmonic distortion caused by phase-controlled parasitic loads
Transient characteristics of voltage regulator and parasitic speed controller on 14.3-kilovolt- ampere, 1200-Hertz modified Lundell alternator
Steady-state characteristics of voltage regulator and parasitic speed controller on 14.3-kilovolt-ampere, 1200-Hz modified Lundell alternator
Analog computer simulation of parasitically loaded rotating electrical power generating system
Low loss parasitic probe antenna for prelaunch tests of spacecraft antennas
VHF/UHF parasitic probe antenna for spacecraft communication
Design of parasitic speed controllers to regulate rotational speed and frequency of alternators in dynamic space power systems
Steady state analysis of phase controlled parasitic current, discussing reduction of alternator apparent power requirements and harmonic distortion
Parasitic speed controller for alternator rotational speed and frequency regulation in dynamic space power systems, investigating phase controlled loading improvement
A circuit for suppressing parasitic oscillations across an inductor operating in a resonant mode is described. The circuit includes a switch means and resistive means connected serially across the inductor. A unidirectional resistive-capacitive network is also connected across the inductor and to the switch means to automatically render the switch means conducting when inductive current through the inductor ceases to flow.
Development of varactor diode assembly overcomes parasitic reactances of conventional varactor packages. In specially constructed assembly very high idler-frequency to signal-frequency ratios are used to obtain low-noise operation over maximum bandwidth.
A system for performing SETI observations continuously as part of non-SETI observations at a radio observatory is presented, and the analysis of results obtained by the parasitic system is discussed. The system, designated SERENDIP, is a real-time microprocessor-controlled spectrum analyzer with algorithms for performing statistical operations and recording those spectra with characteristics presumed to be typical of intelligent rather than astrophysical origin. Programs also exist for the post-acquisition analysis of signal autocorrelation, power spectra, time behavior and positional coordinates, and for a generalized cluster analysis to detect clusters of signal detections. In a recent run of 35 days, the SERENDIP system detected 4000 narrowband spectra exceeding a preset threshold, of which 98% were determined to be of instrumental origin. The remaining class of detections is also believed to be instrumental, although not as well organized as the first signals, and means are currently being sought for eliminating them.