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in subjects: "Electronic Circuits"  
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High-voltage coaxial switch

Description: A coaxial high voltage, high current switch having a solid cylindrical cold cathode coaxially surrounded by a thin hollow cylindrical inner electrode and a larger hollow cylindrical outer electrode is described. A high voltage trigger between the cathode and the inner electrode causes electrons to be emitted from the cathode and flow to the inner electrode preferably through a vacuum. Some of the electrons penetrate the inner electrode and cause a volumetric discharge in the gas (which may be m… more
Date: June 3, 1981
Creator: Rink, J. P.
Partner: UNT Libraries Government Documents Department
open access

Automatic voltage-imbalance detector

Description: A device is described for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.
Date: May 20, 1981
Creator: Bobbett, R. E.; McCormick, J. B. & Kerwin, W. J.
Partner: UNT Libraries Government Documents Department
open access

Control system for a wound-rotor motor

Description: A load switching circuit for switching two or more transformer taps under load carrying conditions includes first and second parallel connected bridge rectifier circuits which control the selective connection of a direct current load to taps of a transformer. The first bridge circuit is normally conducting so that the load is connected to a first tap through the first bridge circuit. To transfer the load to the second tap, a switch is operable to connect the second bridge circuit to a second ta… more
Date: July 17, 1981
Creator: Ellis, James N.
Partner: UNT Libraries Government Documents Department
open access

Compressor surge counter

Description: A surge counter for a rotating compressor is provided which detects surging by monitoring the vibration signal from an accelerometer mounted on the shaft bearing of the compressor. The circuit detects a rapid increase in the amplitude envelope of the vibration signal, e.g., 4 dB or greater in less than one second, which is associated with a surge onset and increments a counter. The circuit is rendered nonresponsive for a period of about 5 seconds following the detection which corresponds to the… more
Date: April 13, 1981
Creator: Castleberry, K.N.
Partner: UNT Libraries Government Documents Department
open access

High-energy-overcurrent protective device

Description: Electrical loads connected to capitance elements in high voltage direct current systems are protected from damage by capacitance discharge overcurrents by connecting between the capacitance element and the load, a longitudinal inductor comprising a bifilar winding wound about a magnetic core, which forms an incomplete magnetic circuit. A diode is connected across a portion of the bifilar winding which conducts a unidirectional current only. Energy discharged from the capitance element is stored… more
Date: May 18, 1981
Creator: Praeg, W. F.
Partner: UNT Libraries Government Documents Department
open access

Transistorized power switch and base drive circuit therefore

Description: A high power switching circuit is disclosed which utilizes a four-terminal Darlington transistor block to improve switching speed, particularly in rapid turn-off. Two independent reverse drive currents are utilized during turn-off in order to expel the minority carriers of the Darlington pair at their own charge sweep-out rate. The reverse drive current may be provided by a current transformer, the secondary of which is tapped to the base terminal of the power stage of the Darlington block. In … more
Date: March 24, 1981
Creator: Lee, F.C. & Carter, R.A.
Partner: UNT Libraries Government Documents Department
open access

Phase-sensitive flow cytometer

Description: This report describes phase-sensitive flow cytometer (FCM) which provides additional FCM capability to use the fluorescence lifetime of one or more fluorochromes bound to single cells to provide additional information regarding the cells. The resulting fluorescence emission can be resolved into individual fluorescence signals if two fluorochromes are present or can be converted directly to a decay lifetime from a single fluorochrome. The excitation light for the fluorochromes is modulated to pr… more
Date: December 31, 1992
Creator: Steinkamp, J. A.
Partner: UNT Libraries Government Documents Department
open access

Laser patterning of laminated structures for electroplating

Description: Disclosed is a process for laser patterning of a substrate so that it can be subsequently electroplated or electrolessly plated. The process utilizes a laser to treat an inactive (inert) layer formed over an active layer to either combine or remove the inactive layer to produce a patterned active layer on which electrodeposition can occur. The process is carried out by utilizing laser alloying and laser etching, and involves only a few relatively high yield steps and can be performed on a very … more
Date: December 31, 1992
Creator: Mayer, S. T. & Evans, L. B.
Partner: UNT Libraries Government Documents Department
open access

Halogenated high {Tc} superconductors and method of preparation

Description: Disclosed is a method for producing a superconductor of the R-Ba-Cu-O system which comprises of selecting an insulating material of the formula RBa{sub x}Cu{sub y}O{sub z} where R is selected from the group consisting of Y, La, Pr, Nd, Sm, Eu, Gd, Ho, Er, Tm, and Lu, and where x ranges from about 1.7 to about 2.3, y ranges from about 2.7 to about 3.3 and z ranges from about 5.0 to about 6.99, and halogenating said material with a halogen selected from the group consisting of chlorine, bromine, … more
Date: November 14, 1990
Creator: Radousky, H. B.; Glass, R. S. & Fluss, M. J.
Partner: UNT Libraries Government Documents Department
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Electronic test circuitry

Description: Circuitry for testing the ability of an intermediate range nuclear instrument to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is ap… more
Date: December 31, 1992
Creator: Brown, R. A.
Partner: UNT Libraries Government Documents Department
open access

Compact acoustic refrigerator

Description: This invention is comprised of a compact acoustic refrigeration system that actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature … more
Date: December 31, 1991
Creator: Bennett, G. A.
Partner: UNT Libraries Government Documents Department
open access

Electrical circuit for data reduction

Description: This invention is comprised of an electrical circuit for determining characteristic voltages, such as maximum, minimum, average and root mean squared voltages, of a time-varying electrical signal. The circuit comprises a positive and a negative peak detector that feed the positive and negative voltage peaks detected in each of a series of time intervals into a solid-state multiplexer controlled by a process controller. The time intervals are generated by the process controller in combination wi… more
Date: December 31, 1991
Creator: Kronberg, J. W.
Partner: UNT Libraries Government Documents Department
open access

Phase stable rf transport system

Description: This invention is comprised of an RF transport system which delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibra… more
Date: February 19, 1991
Creator: Curtin, M. T.; Natter, E. F. & Denney, P. M.
Partner: UNT Libraries Government Documents Department
open access

Method of preparing high-temperature-stable thin-film resistors

Description: A chemical vapor deposition method for manufacturing tungsten-silicide thin-film resistors of predetermined bulk resistivity and temperature coefficient of resistance (TCR) is disclosed. Gaseous compounds of tungsten and silicon are decomposed on a hot substrate to deposit a thin-film of tungsten-silicide. The TCR of the film is determined by the crystallinity of the grain structure, which is controlled by the temperature of deposition and the tungsten to silicon ratio. The bulk resistivity is … more
Date: November 12, 1980
Creator: Raymond, L. S.
Partner: UNT Libraries Government Documents Department
open access

Sensor/source electrometer circuit

Description: A multiple decade electrometer circuit is claimed which can measure low input currents or act as a current source and is comprised of a microprocessor controlled digital to analog converters to derive individual decades. A plurality of decades are created by multiple D-A voltage sources which generate electrometer currents through scaled resistors. After a first series of decades of current are successively produced, the converters are 10 cycled to generate current through new resistors scaled … more
Date: December 31, 1991
Creator: Hughes, W. J.
Partner: UNT Libraries Government Documents Department
open access

Inductive-storage pulse-circuit device

Description: Inductive storage pulse circuit device is disclosed which is capable of delivering a series of electrical pulses to a load in a sequential manner. Silicon controlled rectifiers as well as spark gap switches can be utilized in accordance with the present invention. A commutation switching array is utilized to produce a reverse current to turn-off the main opening switch. A commutation capacitor produces the reverse current and is initially charged to a predetermined voltage and subsequently char… more
Date: January 21, 1982
Creator: Parsons, William M. & Honig, Emanuel M.
Partner: UNT Libraries Government Documents Department
open access

Frequency spectrum analyzer with phase-lock

Description: A frequency-spectrum analyzer with phase-lock for analyzing the frequency and amplitude of an input signal is comprised of a voltage controlled oscillator (VCO) which is driven by a ramp generator, and a phase error detector circuit. The phase error detector circuit measures the difference in phase between the VCO and the input signal, and drives the VCO locking it in phase momentarily with the input signal. The input signal and the output of the VCO are fed into a correlator which transfers th… more
Date: July 29, 1981
Creator: Boland, Thomas J.
Partner: UNT Libraries Government Documents Department
open access

Self-calibrating multiplexer circuit

Description: A time domain multiplexer system with automatic determination of acceptable multiplexer output limits, error determination, or correction is comprised of a time domain multiplexer, a computer, a constant current source capable of at least three distinct current levels, and two series resistances employed for calibration and testing. A two point linear calibration curve defining acceptable multiplexer voltage limits may be defined by the computer by determining the voltage output of the multiple… more
Date: December 31, 1995
Creator: Wahl, C. P.
Partner: UNT Libraries Government Documents Department
open access

Partial core pulse transformer

Description: A light-weight partial-core pule transformer is provided for generating high voltage output pulses with low distortion. The transformer includes sets of ferrite bars arranged so as to extend longitudinally along the inside and outside surfaces of a high frequency cylindrical coil winding-pair. The ferrite bars are arranged in pairs with the bars of each pair being located on opposite sides of winding-pair. The bars are preferably disposed in a radially symmetric arrangement around the winding-p… more
Date: December 31, 1991
Creator: Lawson, R. N. & Rohwein, G. J.
Partner: UNT Libraries Government Documents Department
open access

Vitrification of organics-containing wastes

Description: A process for stabilizing organics-containing waste materials and recovery metals therefrom, and a waste glass product made according to the process are described. Vitrification of wastes such as organic ion exchange resins, electronic components and the like can be accomplished by mixing at least one transition metal oxide with the wastes, and, if needed, glass formers to compensate for a shortage of silicates or other glass formers in the wastes. The transition metal oxide increases the rate … more
Date: January 1, 1995
Creator: Bickford, Dennis F.
Partner: UNT Libraries Government Documents Department
open access

In-line rotating capacitive torque sensor

Description: This invention is comprised of a proximity sensor based on a closed field circuit. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produce… more
Date: December 31, 1991
Creator: Kronberg, James W.
Partner: UNT Libraries Government Documents Department
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