Response of circuits to steady-state pulses

"Reprinted from IRE Vol. 37, No. 12, December, 1949."""March 10, 1951.""A method of calculating the steady-state response of circuits to repeated pulses is given using the method of the steady-state operational calculus. A short table of transforms which have been found useful in these calculations is also presented. The response of several basic circuits to these pulses is obtained and shown as calculated curves, and the calculated curves are then compared with curves obtained experimentally. These curves have been found to be very useful in adjusting circuits to be used with pulses. Several other possible applications are discussed."--Summary

Show Me Your Expertise: 4th Grade Expository Writing Unit

Oftentimes students struggle to distinguish the difference between narrative and expository writing. Therefore this unit is intended to help 4th grade students understand what expository writing truly is, the purpose of expository writing and how it impacts their lives and the lives of others around them. Through composing two expository papers of their own, students will learn that expository texts are the basis for obtaining knowledge and that authors of expository texts develop a greater self-identity and gain perspective as they write expository texts

Steady-state waves on transmission lines

"June 1, 1951.""Reprinted from Trans. AIEE, Vol. 69, 1950.

Coating thickness measurements using pulsed eddy currents

"July 1,1955.""Reprinted from the Proceedings of the NATIONAL ELECTRONICS CONFERENCE, Vol. 10, February 1955.""The nondestructive measurement of the thickness of one metal coated or clad upon another metal as a base has been studied for the past twenty years or more. If one of the metals is magnetic, the problem is relatively simple. If the clad and base metals are both nonmagnetic, the measurement problem is more difficult, particularly if both metals have nearly equal electrical conductivities. The phase measurement of sinusoidal eddy currents has been tried with some success although there is difficulty with low sensitivity and the presence of harmonic frequencies. The use of pulsed eddy currents in the manner of echo sounding appeared to have promise and was tried. A brief theoretical treatment indicated that the necessary pulse length depended upon the thickness of the coating. For thickness of the order of ten mils of coating, pulse lengths of approximately one microsecond were found satisfactory. A thyratron was used to pulse the magnetic probe, while a balancing circuit was employed almost to eliminate the echo from the air-to-metal surface so the echo from the metal-to-metal boundary could be detected. Several different forms of the balancing circuit were tested. Comparison of thicknesses measured using the pulsed probe is made with those measured optically."--Page 1

Meaning behind the Structure: 4th Grade Nonfiction Text Structure and Summary Unit

Nonfiction texts are summarized much differently than fictional texts. In order for students to be able to summarize a nonfiction text, they need to be able to recognize how the text is organized. In this unit, students will learn to identify various common text structures that will then help them create summaries of these texts

The design of a single-layer microwave absorbing material

"September 7, 1959.""Reprinted from Volume XIV, Proceedings of the National Electronics Conference, Hotel Sherman, Chicago, Illinois, October 13, 14, 15, 1958."The microwave absorbing structure considered here consists of a homogeneous lossy dielectric material backed by a good conductor. Some previous work has been done on obtaining the electric and magnetic parameters of a suitable dielectric assuming that the magnetic dissipation factor was zero. With the wide spread use of ferrites at microwave frequencies, design information assuming a finite magnetic dissipation factor is needed and is presented. The special cases of zero electric dissipation factor, zero magnetic dissipation factor and equal electric and magnetic dissipation factors are also considered. Possible values of the electric and magnetic parameters of the absorbing material are obtained and the resulting thickness is presented. A method of choosing the parameters for the smallest thickness of dielectric is given. Little information has been available as to the possible band width of such a structure. An expression for the band width is derived for a given power reflection coefficient. The parameters of the absorbing material necessary for the greatest band width are indicated

Pulsed eddy currents gage plating thickness

"March 1, 1956.""Reprinted from Electronics vol. 28, page 146, November 1955.""Echo-sounding technique making use of pulsed eddy currents determines thickness of one metal coated on a base metal. System takes advantage of electrical dissimilarities and is effective even when both metals are nonmagnetic."--Summary

Circuit waveforms for periodic waves

"February 16, 1964.""Reprinted from Communication and Electronics March 1963.""A method using steady-state transforms is described which indicates how the sum function of a Fourier series may be obtained. The method can be applied to problems arising from circuits containing concentrated circuit parameters, but is not quite so useful for those having distributed parameters. Tables of Fourier series and their sum functions are presented, and several examples of the application of the method in circuit problem are given in this paper."--Page 1

Design of optimum phase-shift oscillators

"January 1, 1957.""Reprinted from Proceedings of the National Electronics Conference, Vol. 11, Page 222, 1955 ; This article also appeared in Electronic Equipment, Vol. 4, Page 38, April, 1956."In the designing of phase-shift oscillators it is advantageous to make the loss in the phase shift circuit a minimum, so that an amplifier of minimum gain may be used. A method of obtaining such a design has been developed which seems applicable to any one of the great variety of phase-shift oscillator circuits. This method is applied to two different phase-shift oscillators to obtain design equations and curves. The first example is that of one of the most common phase-shift oscillators. The results appear to agree with those obtained by a previous analysis which does not have the versatility of the present method. The second example is that of one of the relatively new cathode-follower phase-shift oscillator circuits which seem to have promise in the development of low-distortion oscillators. Since the gain of a cathode-follower amplifier is below unity, the determination of optimum phase-shift circuits becomes extremely important