Pulsating auroral electron flux modulations in the equatorial magnetosphere
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A. N. Jaynes↗
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Results for “ELECTRONIC MODULE”
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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S-band and X-band central frequency synthesizer at the Venus Deep Space Station
Direct current power consumption for S-band and X-band central frequency synthesizer - electronic module
X-BAND↗
Dynamic-pressure measurements using an electronically scanned pressure module
Frequency response was measured for different lengths and diameters of tubing between a sinusoidal pressure source and a pressure sensing module from an electronically scanned pressure measuring system. Measurements were made for straight runs of both steel and vinyl tubing. For steel tubing, measured results are compared with results calculated by using equations developed by Tijdeman and Bergh. Measurements were also made with a bend in the vinyl tubing at the module. In addition, measurements were made with two coils placed in the tubing near the middle of the run.
Chapin, W. G.↗
Design and Operation of the Planetary In-Situ Capillary Electrophoresis System (PISCES)
The PISCES instrument is a portable, miniature, modular instrument designed to analyze organic molecular signatures of life. PISCES uses microcapillary electrophoresis (μCE) with laser-induced fluorescence detection (LIFD) to analyze fluorescently-labeled analytes prepared on a multi-layer microfluidic chip. As a modular instrument composed of five independently functioning units, each module can be easily detached from the system and used for subsystem testing in different environments, e.g. low temperature. The pneumatic module contains mechanical and electrical components necessary to control pneumatically-actuated valves for on-chip sample processing. A prototype LabVIEW program and two custom printed circuit boards (PCBs) operate the pneumatics module using an Arduino microcontroller, and a tentative design for the module’s housing has been developed. The high-voltage module contains circuitry required to apply varying electrical potentials to the electrophoretic channel of the microdevice. Work is currently being done to design the circuit and PCB for this module in collaboration with our SBIR partners at Los Gatos Research. The optical electronics module contains the spectrometer, laser, and laser power supply. The mounting components for the electronics and housing for the module have been designed, assembled, and tested. The optical module contains optical components to focus the laser to a 20μm spot in the center of the electrophoretic channel.The housing for this module has been designed and assembled with the aligned optical components inside.
Willis, Peter A.↗
The generation of rapid solar flare hard X-ray and microwave fluctuations in current sheets
The generation of rapid fluctuations, or spikes, in hard X-ray and microwave bursts via the disruption of electron heating and acceleration in current sheets is studied. It is found that 20 msec hard X-ray fluctuations can be thermally generated in a current sheet if the resistivity in the sheet is highly anomalous, the plasma density in the emitting region is relatively high, and the volume of the emitting region is greater than that of the current sheet. A specific mechanism for producing the fluctuations, involving heating in the presence of ion acoustic turbulence and a constant driving electric field, and interruption of the heating by a strong two-stream instability, is discussed. Variations upon this mechanism are also discussed. This mechanism also modulates electron acceleration, as required for the microwave spike emission. If the hard X-ray emission at energies less than approx. 1000 keV is nonthermal bremsstrahlung, the coherent modulation of electron acceleration in a large number of current sheets is required.
Holman, Gordon D.↗
Test device prevents weld joint damage by eliminating axial pin forces on unpotted modules
Test device makes electrical connection to pins on unpotted electronic modules without introducing any displacing forces of the pins, thus preventing weld joint damage. The pins are spaced in a potting header, but are free to slide in and out except for restraint from welded wire joints.
Cree, R. E.↗
Efficient modulation coupling between electron and ion resonances in magnetoactive plasmas
Modulation coupling between electron and ion resonances in magnetoactive plasmas, discussing probeless feedback stabilization scheme
Baker, D. R.↗
N2O analysis in the atmosphere via electron capture-gas chromatography
The potential of commercially available pulse-modulated electron capture detector (ECD)-equipped gas chromatographs for direct measurement of ambient levels of N2O is assessed. Since the sensitivity of ECD to N2O is directly proportional to the detector operating temperature and detector standing current, it is necessary to use a 'hot' ECD (250-350 C). The method is shown to be very precise with a standard error not exceeding 1% for automated analysis of ambient air samples. The technology is available to permit highly accurate routine direct analysis of N2O in the troposphere and stratosphere. Both captured air samples or direct real-time measurement from research vessels or airborne platforms are possible.
Rasmussen, R. A.↗
Development of a width-modulated pulse rebalance electronics loop for strapdown gyroscopes
A new width modulated pulse rebalance electronics loop was developed for use with strapdown gyroscopes. Advantages of the width modulated binary over the ternary loop are the following: (1) The H-switch is easier to implement; (2) torque is applied in finely quantized increments; (3) the analog-to-digital conversion for data generation is inside the loop and is directly determined by the torque pulse; (4) on part of the loop compensation network bypasses the gyroscope; and (5) the torquer is fed constant power.
Blalock, T. V.↗
The determination of transport parameters of minority carriers in n-p junctions by means of an electron microscope - Critique of recent developments
It has recently been shown that amplitude modulated electron beams provide a novel means for the determination of minority carrier lifetimes, diffusion lengths, etc., in n-p junctions. In this paper it is shown that: (1) a recently published analysis based on a cylindrically symmetric configuration is incorrect, (2) the correct approach leads to a system of dual integral equations for which the formal solution is given, (3) in general, the short circuit current can only be determined by means of extensive computer calculations except in the case of large front surface recombination velocities, and (4) the difficulties encountered with cylindrically symmetric configurations (circular ohmic contacts and the like) are completely avoided with a choice of a planar geometry since simple closed form expressions for the short circuit current are readily available in this case.
Von Roos, O.↗
Photonic Integrated Circuits
Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.
Laser↗
Photonic Integrated Circuits
Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.
laser↗
Determination of deep level capture cross sections in wide band-gap semiconductors by means of an electron beam
The paper presents a general theory for the determination of the short circuit current generated by a sinusoidally amplitude-modulated electron beam in the presence of recombination centers with an arbitrary number of charge states. It is shown that a measurement of the coherent phase shift with respect to the incident beam as a function of the modulation frequency of the beam ascertains the magnitudes of electron and hole capture cross sections. The surface exposed to the electron beam must have a negligible surface recombination velocity for the measurements to be unambiguous.
Von Roos, O.↗
Non-Io-related radio emissions and the modulation of relativistic electrons in the Jovian magnetosphere
The modulations of the non-Io-related radio emissions in hectometric and decametric wave frequencies are examined, and compared with the observed variation of the MeV electron fluxes in the morning sector of the Jovian magnetosphere. It is suggested that these radio emissions are controlled by the behavior of these electrons in this sector.
Sakurai, K.↗
A cryogenic multichannel electronically scanned pressure module
Consideration is given to a cryogenic multichannel electronically scanned pressure (ESP) module developed and tested over an extended temperature span from -184 to +50 C and a pressure range of 0 to 5 psig. The ESP module consists of 32 pressure sensor dice, four analog 8 differential-input multiplexers, and an amplifier circuit, all of which are packaged in a physical volume of 2 x 1 x 5/8 in with 32 pressure and two reference ports. Maximum nonrepeatability is measured at 0.21 percent of full-scale output. The ESP modules have performed consistently well over 15 times over the above temperature range and continue to work without any sign of degradation. These sensors are also immune to repeated thermal shock tests over a temperature change of 220 C/sec.
Shams, Qamar A.↗
Electron Beam Could Probe Recombination Centers
Electron beam probe technique estimate electron/hole capture cross sections in semiconductors with wide band gaps. Amplitude-modulated electron beam induces short-circuit current collected by ohmic contacts. Phase shift between this current and electron-beam current measured as function of frequency. Results of measurements used to ascertain recombination rates and energy levels.
Vonroos, O.↗
Investigations of radiation-induced and carrier-enhanced conductivity
A steady-state carrier computer code, PECK (Parker Enhanced Carrier Kinetics), that predicts the radiation-induced conductivity (RIC) produced in a dielectric by an electron beam was developed. The model, which assumes instantly-trapped holes, was then applied to experimental measurements on thin Kapton samples penetrated by an electron beam. Measurements at high bias were matched in the model by an appropriate choice for the trap-modulated electron mobility. A fractional split between front and rear currents measured at zone bias is explained on the basis of beam-scattering. The effects of carrier-enhanced conductivity (CEC) on data obtained for thick, free-surface Kapton samples is described by using an analytical model that incorporates field injection of carriers from the RIC region. The computer code, LWPCHARGE, modified for carrier transport, is also used to predict partial penetration effects associated with CEC in the unirradiated region. Experimental currents and surface voltages, when incorporated in the appropriate models, provide a value for the trap modulated mobility that is in essential agreement with the RIC results.
Meulenberg, A., Jr.↗
Distributed Motor Controller (DMC) for Operation in Extreme Environments
This paper presents an extreme environment capable Distributed Motor Controller (DMC) module suitable for operation with a distributed architecture of future spacecraft systems. This motor controller is designed to be a bus-based electronics module capable of operating a single Brushless DC motor in extreme space environments: temperature (-120 C to +85 C required, -180 C to +100 C stretch goal); radiation (>;20K required, >;100KRad stretch goal); >;360 cycles of operation. Achieving this objective will result in a scalable modular configuration for motor control with enhanced reliability that will greatly lower cost during the design, fabrication and ATLO phases of future missions. Within the heart of the DMC lies a pair of cold-capable Application Specific Integrated Circuits (ASICs) and a Field Programmable Gate Array (FPGA) that enable its miniaturization and operation in extreme environments. The ASICs are fabricated in the IBM 0.5 micron Silicon Germanium (SiGe) BiCMOS process and are comprised of Analog circuitry to provide telemetry information, sensor interface, and health and status of DMC. The FPGA contains logic to provide motor control, status monitoring and spacecraft interface. The testing and characterization of these ASICs have yielded excellent functionality in cold temperatures (-135 C). The DMC module has demonstrated successful operation of a motor at temperature.
SiGe↗