INTRODUCTION
Around 1875, Oliver Heaviside pioneered high speed pulse signalling down a coaxial undersea cable between Newcastle and Denmark. This led to his theory of electromagnetism, which runs to five volumes. His approach is based on the TEM wave travelling at the speed of light down a dielectric guided by two conductors. Development of the more glamorous wireless signalling around 1900 erased Heaviside's approach. In 1960, when the centre of gravity reverted to Heaviside's problem, this time on the back plane of a digital computer, Heaviside and his earlier approach had disappeared from the record. A quick check in the indexes of today's text books on electromagnetism will show that, along with Heaviside, the TEM wave has virtually disappeared from today's electromagnetic theory. What little mention there is, is confusing. One book calls the TEM wave a degenerate form! As data rates increase, wired communication comes more and more into the fore. I adopt the approach appropriate to the new situation, very much centred on the guided TEM wave. This book comes after a long gap in the author's publications on electromagnetism, which began a quarter of a century ago with a major paper revolutionising the theory of crosstalk in the IEEE Transactions on Computers, December 1967. Previous books are listed in the Cumulative Index at the end of this book. Text book writers of the last fifty years seem to have fed on each other. Confusion has accumulated as writers with no practical experience of the art have copied and re-copied each other. Generally, a growing welter of dubious and irrelevant mathematics has submerged the subject. Their divorce from practical experience of driven waves (as opposed to the standing waves of wireless and radar) makes the present challenge, to bring the art back to the Heaviside mainstream, difficult but rewarding for the author and for the reader. Bizarre extremes adopted as quick-fixes in 'modern physics' further confuse the subject, which should be reasonably straightforward. Ivor
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