Sunday 29 January 2012

Engineers & Electrons: A Century of Electrical Progress

Engineers & Electrons: A Century of Electrical Progress
by Dennis L. Feucht

Written by two IEEE Centennial Task Force chairmen, this book reflects upon the history of electrical engineering from its inception in the late 1700s and 1800s, until the early 1980s. It was written on the occasion of the centenary of the IEEE, including its predecessors. Now, over twenty years later, the book is still current in most aspects, and it is interesting to read engineers reflecting on EE in 1984, a year in which Apple II computers were still in vogue and the IBM PC was early in its product life -- long before the Pentium and commercial submicron circuitry had arrived.
Our craft was dominated in the early years by invention and discovery (Chapter 2). So much that we now take for granted was not even known, including the safety aspects of electricity. While the book covers the important early contributions of Morse, Edison, and Bell, it also pays attention to Charles Brush, Elihu Thomson, and Edward Weston, also major contributors. The electrical industry was growing rapidly in the 1880s, and one of the major decisions was whether to use ac or dc for power distribution. Edison backed dc while Westinghouse, who had acquired the patent rights to the polyphase ac motor invented by Nikola Tesla, was chosen to supply power to the Chicago World's Fair in 1893 using ac. In 1892, Elihu Thomson's Thomson-Houston Company merged with the Edison interests to form the General Electric Company. Edison was named a director, but his interest in electric power by then had run its course, and Westinghouse led further development, along with such participants as the Brown-Boveri Company in Switzerland at which three-phase power was demonstrated early. Comparable developments in Britain and Germany kept Europe apace, or sometimes ahead, of American development.
Charles Proteus Steinmetz also entered the scene in the late 1800s, appearing at GE near its inception. Besides working out motor theory, for which he is best known, Steinmetz also promoted the use of some of the key mathematics we use in EE today. A E Kennelly, an Edison employee, had written a key paper on impedance, and in it Steinmetz grasped the importance of using j = square root of -1, and the complex plane in ac circuit calculations. Steinmetz said that (p 43) " by reducing the electrical problems to the analysis of complex quantities they are brought within the scope of a known and well understood science." From that time Steinmetz and another frequent contributor to the AIEE Transactions, Michael Pupin, used complex quantities in their papers instead of the better-known graphical method of ac analysis using phasors.
It was also in the 1890s that RLC circuit response solutions were worked out, units (such as the "henry," proposed by Kennelly) were proposed, and the need for agreement on the names of circuit elements recognized. An increasing use of mathematics in EE was a sign of the passing of the "electricians" and the rise of the engineers.
In Chapter 4, Maxwell's Prophecy Fulfilled, the electron is identified in 1897 by J J Thomson, Hertz and Marconi appear, and wireless arrives. In 1906, Lee deForrest invented the audion, the first triode vacuum tube (or thermionic valve), and industrial research began at GE (though it had been born in Edison's labs earlier -- see my review of Edison and the Business of Innovation by A. Millard). Bell Labs also commenced and MIT began to appear as an important EE school.
About a decade later, in 1913, Armstrong invented the regenerative circuit, giving radios better sensitivity. Independently in Europe Fessenden, Meissner, and Round originated circuits giving somewhat similar results. Langmuir and Arnold contributed toward making the triode a useful device. In 1918 Armstrong invented the superheterodyne. He went on to also invent super regeneration and FM. Also, the AIEE began establishing membership grades and requirements. Chapter 5 continues the radio story, bringing in David Sarnoff and RCA, which was "founded on an agreement that called for cross licensing of AT&T, GE and Westinghouse patents in the field of radio. While this arrangement freed the industry of its internecine patent fights, it also placed tremendous power in one corporation." (p 71) As the radio story moves on, Alan Hazeltine and Daniel Noble appear.
Then the scene changes (p 83) to a Hudson River Ferry commute to work in 1927 by Bell Labs employee Harold S Black who "scratched out a solution to a longstanding problem on a page of the New York Times" and thus invented "negative feedback."
After more detail on turn-of-the-century development, Chapter 7 brings in semiconductors, with post-WW-II background in the MIT Radiation Laboratory and Karl Lark-Horovitz at Purdue University researching germanium. The Bell Labs invention of the transistor -- first the point-contact, then the BJT -- culminate in a picture of Andrew Grove, Robert Noyce, and Gordon Moore on p 128, posing before a light table with a rubylith layout of an IC before them. WW-II innovations (Chapter 8) include only those with useful peacetime applications, such as radar, sonar, navigation, and the post-war communications satellite, first proposed by SF writer Arthur C. Clarke in the British journal, Wireless World in October 1945.
Next: television. Nipkow disks are given extraordinary coverage, but finally RCA's Vlad Zworykin, who worked out the critical element, the video imager, is followed by another major contributor, though not as well remembered: Philo T Farnsworth. How the NTSC video encoding standard -- which included a color scheme compatible with monochrome -- came about is a story in itself, also recounted here.
Chapter 10 covers the development of electronic computers. Babbage is credited with the general invention of stored-program computation, using mechanical implementation. Appearing in the story are Grace Hopper, Herman Hollerith and IBM, Howard Aiken, Eckert and Mauchley of ENIAC renown, and the Intel 4004.
Chapter 11 discusses the history of EE education, of how it had an early theoretical emphasis, swung to the other extreme during the stagnant years from 1900-1935 (despite Steinmetz's advice), then came back to a more needed theoretical coverage in the 1940s. I found it surprising that the level of engineering education in the early 20th century was so much like high-school shop classes, emphasizing practical proficiency. Even mechanical engineering professors taught little thermodynamics because it was considered too difficult. Differential equations appeared only in graduate school. Few college teachers held masters degrees, and far fewer had doctorates. Although every professor had a radio in his home, there was little thought about change in the field. By 1925 complex algebra had not even appeared in some circuits textbooks. WW-II made a tremendous impact on EE education. By 1950 semiconductor electronics was in view. The authors conclude about the present state of education: "The physical theory ignored in the 1900 - 1930 decades must now be studied as fundamental to most of our electrical theory."
The final chapter (Chapter 12) covers the history of the IEEE as the merger of the AIEE and IRE. The familiar IEEE logo evolved from earlier badge symbolism. Lists of the presidents of the three organizations are given in the Appendix.
Although this book can be read by a wider intelligent audience, it does have enough detail to give the EE a sense of continuity with the past. Since 1984 much has occurred in EE, yet the basic directions were established within the time preceding the writing of this book. For those interested in the wider aspects of EE, I recommend adding a (probably used) copy of this book to your engineering library. Maybe the IEEE Press still has some new copies for sale.

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