Electrical and Computer Engineering Commons^™

Safe Thermal Operation Of Power Transistors Under Pulsed Excitation, George R. Swain

Electrical and Computer Engineering ETDs

One desires to find the relationship between thermal stability and such factors as temperature within the transistor, power dissipation in the transistor junctions, collector saturation current, and thermal resistance. In the approach set forth in this paper, the theory of solid state heat flow is applied to a simplified thermal model of a power transistor.

The Design, Construction And Testing Of An Electrical, Transient Heat Flow Analyser, Bruce Wilcox

Electrical and Computer Engineering ETDs

The purpose of this investigation was (a) to design and build an analog which would produce the solution to a simplified yet typical transient aerodynamic heating problem, (b) to obtain the solution using the analog and to check the accuracy of the solution by mathematical computation, and (c) to code a more involved aerodynamic analog.

Comparison Of Observed And Calculated Near-Vertical Radar Ground Return Intensities And Fading Spectra, James Arlin Cooper

Electrical and Computer Engineering ETDs

The study of ground-to-air terrain return is necessary in order to understand the functioning of radar altimeters.

Radar return at vertical incidence can be considered to be composed of two components. One, whic his returned by a mirror-like action, is called the specular component. The other, termed scatter, is due to diffuse rerediation from individual scatterers on the ground.

In recent work on return from angles near vertical, more attention has been given to the scatter component than many had previously assumed necessary.

Procedure for Gathering Data:

Two pulse radar units were used, one having a frequency of 3.8 KMC, …

Design Of An Experiment To Separate Specular And Scattered Radar Returns, Robert B. Glascock

Electrical and Computer Engineering ETDs

This paper describes the design of a radar experiment that will be conducted by the U.S. Naval Research Laboratory at Washington, D.C. The proposed experiment and the background of the problem are discussed, as well as the theoretical background, experimental background, and other design considerations are discussed in later sections.

A Study Of The Reset Cycle Of A Half-Wave Self-Saturable Magnetic Amplifier, William W. Lee

Electrical and Computer Engineering ETDs

It was the purpose of this study (1) to investigate the reset cycle of a half-wave self-saturable magnetic amplifier by graphical analysis of the irregular voltage functions appearing across the gate winding during reset; and (2) to determine if possible from this analysis a more satisfactory design method than those now available. Conditions of constant current reset were employed and the core material used had a nearly rectangular hysteresis loop. Resistive loads only are considered.

Utilization Of The Relationship Between The Complex Immittance And The Indicial Immittance Functions For The Synthesis Of Two Terminal Networks, Julian T. Lefler

Electrical and Computer Engineering ETDs

It was the purpose of this study (1) to develop a new method of network synthesis from a specified complex immittance function; and (2) to demonstrate the application of the method by means of its use in the solution of representative synthesis problems. This work deals only with the synthesis of two terminal networks containing linear, passive, lumped-constant elements, from given rational immittance functions of the complex frequency variable.

Not considered part of this work are (1) the development of the immittance function from frequency-response specifications (the approximation problem); or (2) the treatment of active, non-linear, or time varying network …

A Study Of A Complementary Symmetrical Power Switching Circuit, Glenn S. Mills

Electrical and Computer Engineering ETDs

This paper contains an analysis of a symmetrical, complementary, power switching circuit employing complementary power transistors. A DC analysis is made for the bistable states. Also described is a voltage regulation and bias circuit which improves stability and contributes to the protection of the transistors. The problem of switching transients is investigated and empirical results presented to support theoretical considerations. A new triggered method is proposed to utilize the bilateral characteristics of a transistor. Applications of the circuit are suggested for controlled-frequency and self-triggering modes of operation. A method and analysis for self-triggering is presented. The advantages of this power …

The Use Of Electrical Resistance Strain Elements In Three-Dimensional Stress Analysis, Robert I. Brasier

Electrical and Computer Engineering ETDs

The purpose of this thesis is to present a new method of experimental stress analysis and to give the solution to a problem which has been handled by this method.

Determination Of Q Factors And Operating Characteristics For Microwave Cavities And Oscillations, W.P. Stearns

Electrical and Computer Engineering ETDs

This paper has as its objective the presentation of the theory involved and method used with respect to the resonant cavity parameters; loaded Q, unloaded Q, external Q, pulling figure, and circuit efficiency for the resonant cavity investigated. Experimental data on a particular cavity are discussed and the previously mentioned cavity parameters determined with the use of such data and the particular method presented. A Rieke diagram for the particular cavity investigated is also presented and discussed.

Transients And Saturation In Synchronous Machines, Sabi J. Asseo

Masters Theses

"The synchronous machine can be regarded as the most important electrical device in today's industry and civilization. Although many improvements in the development of powerful electronic devices have been made, in recent years, the importance of the electrical power engineering field can never be overlooked in any way.

Most of electrical power engineering problems have been studied in the first quarter of the present century, and the results applied to industry for the betterment of electrical power production. As distribution and transmission systems used become extensively large, new problems such as the stability of interconnected power systems, have been introduced. …

The Status Of Applied Electricity In Selected Colleges And Secondary Schools In Kansas, Karl E. Cunningham

Electronic Theses & Dissertations

This study was developed on the premise that applied electricity was a current and future need of such dimensions that it demanded more attention by educators. An attempt was made to determine the present status of teaching applied electricity in selected colleges and secondary schools in Kansas with a view to developing and/or improving programs in the area. Objective data were obtained by surveys of secondary school administrators, industrial arts supervisors, and instructors who taught applied electricity as a separate course or as a unit in a composite general shop. Additional information and statistics were derived from books, periodicals, published …

An Investigation Of The Response Of A Velocity Sensing Resonant Oscillator In An Inertially Operated Distance Meter, Howard F. Devaney

Electrical and Computer Engineering ETDs

It was the purpose of this study to investigate the response characteristics of a resonant mechanical oscillator utilized as a governor in conjunction with an inertial distance meter to sense velocity of a carrier. In order to initiate any desired event at a predetermined velocity of a vehicle (for example: fuel cut-off in a conventional liquid fuel rocket motor) it is often desirable to utilize a component requiring no external power for its operation. Such a component would be activated by inertial force and, by some means, integrate the force (or acceleration) with one respect to time and provide a …

The Rating Of A Power Type Transistor, Richard Lee Mann

Electrical and Computer Engineering ETDs

The purpose of this paper is to describe the test performed and present the results obtained in an attempt to establish the maximum permissible direct current and pulse ratings for the type of CTP-1003 (Clevite Transistor Products) power transistors under typical operating conditions. The manufacturer's specifications for the type of CTP-1003 power transistor are located in Appendix A.

The Dc Design Of Reliable Multistable Circuits, Richard H. Williams

Electrical and Computer Engineering ETDs

The reliability of a piece of equipment is a measure of its ability to function as intended. Equipment may malfunction in two different ways. It may fail catastrophically as a vacuum tube does when its heater opens; it may fail gradually as a vacuum tube does when its transconductance slowly falls to an unacceptable level over a period of time. It is not the intent of this paper to study catastrophic component failures, but rather to illustrate a technique whereby gradual failure of circuits can be minimized.

A Binary-To-Decimal Converter, Samuel D. Stearns

Electrical and Computer Engineering ETDs

This paper describes a device which electronically converts a binary number into its decimal equivalent. Such a device might be of use in digital computers, many of which use the binary number system, and also in similar machines, such as pulse code modulated data collectors.

The binary-to-decimal converter described here was designed specifically for use in Sandia Corporation's High-Speed Digital Recording and Data Handling System, which actually uses the Gray code rather than the binary number system. However, conversion from Gray to binary (see Appendix B) is simple, and a binary-to-decimal converter seems much simpler than a Gray-to-decimal converter.

Temperature Stabilized Transistor Direct Current Amplifier, William Lewis Metcalf Jr.

Masters Theses

"A stable direct current transistor amplifier is difficult to design for use at elevated temperatures. The above is true since transistor parameters and bias conditions are affected by temperature. When transistors are incorporated in direct coupled amplifier circuits, these variations in parameters and bias conditions usually result in unstable operation. It is the purpose of this thesis to investigate this problem and to design a stable direct current transistor amplifier which will operate satisfactorily at elevated temperatures.

This problem is of importance as such direct current amplifier circuits are found in airborne or missile servo systems. In such systems the …

Servomechanism Compensation With An Active Phase-Lead Network, Robert T. Dewoody

Masters Theses

"The problem is to develop a phase-lead compensation network for a servomechanism which will not reduce the low-frequency gain and thus decrease the velocity-lag error. The principal part of this thesis deals with the design of such an active phase-lead network. The active network does not have d-c coupling; this eliminates drift problems.

To illustrate an active phase-lead network a simple second order servomechanism is used as a basis for comparing three methods of compensation.

The first method is compensation with a conventional phase-lead network with a gain decrease. The second method is compensation with a conventional phase-lead network with …

Transistors Applied To An Fm-Fm Airborne Radio Telemetery System, R. H. Gablehouse

Electrical and Computer Engineering ETDs

The two semiconductor elements commonly used in transistor production, silicon and germanium, were discovered by two European chemists. A Swedish chemist, Jons Jakob Berzelius, separated and identified silicon in 1823. Germanium was discovered and named by a German chemist, Clemens Alexander Winkler in 1886.

A Technique For Obtaining Submicrosecond Exposure Times At Large Aperture In High-Speed Photography, Joseph A. Hull

Electrical and Computer Engineering ETDs

The purpose of the investigation described in this report was to attempt to improve one of the existing techniques, namely, the Kerr cell type electrooptical shutter, to make it more applicable to the study of high-explosive physics. To provide a background for the reader, a brief discussion of the other techniques will be described. Some of the advantages and limitations of these systems will be discussed.

Determination Of The Residual Vswr [Voltage Standing Wave Ratio] Of A Slotted Line., Michael C. Robel

Electrical and Computer Engineering ETDs

Idealistically, a slotted line should be designed so that, when it is terminated in its characteristic impedance, the VSWR as determined by a movable probe in the slotted line will be 1.0. However, in practice this is not possible, particularly in the case of coaxial slotted lines where matching elements, adapters and connectors are utilized. The devices mentioned above have physical discontinuities which give rise to reflections, which cause a standing wave to be produced even though the line is terminated I its characteristic impedance.

High Stability Lc Oscillator For Use With A Capacitive Pressure Sensing Element, Arthur J. Eldridge

Electrical and Computer Engineering ETDs

In the course of work at the Sandia Corporation, a definite need arose for the measurement of barometric pressures to an accuracy beyond that attainable with commercially available equipment. The standard instrument for measuring these pressures is the mercurial barometer. While a visual method of reading the instrument produced good results to within a 0.1 millimeter of mercury, it was dependent upon the operator using as a reference a target of sighting on the top of the meniscus formed in the barometer tube by the mercury.

Corona Threshold Of Single And Multiple Conductor Lines, David S. Carrick

Electrical and Computer Engineering ETDs

Corona is a self sustaining, often luminous discharge due to ionization adjacent to charged conductors, characterized by the electrodes having a small radius of curvature compared with the interelectrode gap. The display on a power transmission line is accompanied by a current between the conductors which to an engineer mean a power loss that should be minimized if unavoidable.

The Effect Of Today's Residential Electric Consumer On The Planning, Design, And Operation Of Electrical Distribution Systems, James Wilbur Stephens

Professional Degree Theses

"The purpose of this paper shall be primarily to show the present day trends in the use of electricity by the residential consumer and the effect of such trends on the design, planning, and operation of the electric distribution system. System planning related to the electric utility is divided into two classes. The first deals with generation. The second deals with distribution from the various load and transmission centers to the customer. This thesis will deal .primarily with studies related to the latter.

Many utility distribution system problems have been brought about by the rapidly increased demands for residential uses …

Investigation Of The Current Distribution On An Antenna In A Waveguide, David J. Freeman

Masters Theses

"In a communication system composed of several networks and transmission systems, it is necessary for all parts of the system to be impedance matched so that medium energy transfer is possible.

One of the recent transmission systems which has been developed is the wave guide. With the advent of the wave guide the communication engineer is immediately faced with the problem of coupling existing systems and networks to his newly found mode of transmission.

Practically this coupling problem reduces to one of feeding radio frequency energy to the wave guide with some conventional transmission line such as a coaxial line. …

A Proposal For Two Computers Dealing With The Convolution Integral, Charles S. Williams Jr.

Electrical and Computer Engineering ETDs

The integral f(x) = g(x-y)h(Y)dy is known as a convolution integral. The first computer described herein will determine the function f when the functions g and h are known. The second computer will determine the function h when f and g are known; in using the second computer to find h, then the first computer is used for auxiliary computations.

A Study Of Servomechanism Damping Methods, Arthur J. Clark Jr.

Electrical and Computer Engineering ETDs

The purpose of this study is first to present a review of the general effects of damping, both Coulomb and Viscous, and feedback devices resulting in error rate damping: second to present detailed mathematical analyses of a number of special damping devices that may be used to advantage in servomechanism design.

Crossover Networks For Loudspeakers, Edward A. Brown

Electrical and Computer Engineering ETDs

No abstract provided.

A Variational Approach To The Calculation Of Electron Trajectories, Edmund G. Franzak

Electrical and Computer Engineering ETDs

It is the object of the present work to derive, develop, and illustrate a method for the calculation of electron trajectories based on variational techniques and employing scalar and vector potential functions instead of the customary intensity functions. The methods of the calculus of variations furnish an extremely basic approach to the problem while lending an undeniable air of rigor and mathematical elegance.

Solution of the problem will be accomplished by first setting forth a mathematical structure upon which the work will be based, next outlining the physical principles governing the problem and finally applying the mathematical theory and physical …

Design Of A Subsonic Wind Tunnel Electrical System, William A. Wundrack

Professional Degree Theses

"The purpose of this thesis is to present information and data used in the planning and construction of an electrical distribution system and main drive system for a wind tunnel designed for Chance Vought Aircraft Company of Dallas, Texas, by Sverdrup & Parcel, Incorporated, Consulting Engineers of St. Louis. Preliminary negotiations were started with Chance Vought Aircraft Company in March 1953, and the wind tunnel calibrations were started in October 1954. Between those dates all design, installation drawings, and construction were completed.

The data used in preparing this thesis were taken from daily records, records of conferences, personal records, correspondence …

Mechanical Vibration Of Vacuum Tubes, Jerry Dale Swearingen

Masters Theses

"Since the beginning of the art of vacuum tube building, vacuum tube engineers have been faced with many mechanical problems as well as electrical problems.

Early mechanical problems were comparatively small because most of the tubes were used in stationary apparatus where little or no vibration was envolved.

As time went on, vacuum tubes were placed in portable equipment and this useage established the need for a tube that was mechanically strong enough to give reliable electrical behavior where the tube was subjected to considerable vibration….

Recently it has been shown that vacuum tubes operating in the instrument cabins of …