Division 6: SOLID-STATE DEVICES AND CIRCUITS

FUNDAMENTALS OF ELECTRONICS

1. From vacuum tubes to transistors. The science of electronics was founded on the ability of the electron tube (most importantly, the vacuum tube) to generate, amplify, and control an electric signal to accomplish a wide variety of functions. During its half-century dominance of the electronics art, the vacuum tube fostered the invention of radio, television, and radar, of factory automation and computers, and indeed of all the phenomena that we associate with electronics even today. Yet, with the invention of the transistor by Bell Laboratories in 1948, the tube was headed for extinction. Today, except for a few special functions, it no longer occupies an important place in electronic technology.

In place of the electron tube, the transistor has emerged as the cornerstone of modern electronics. Based on the theory of electron conduction in a solid crystalline material rather than in a vacuum or a gaseous environment, the transistor not only can perform virtually all the functions formerly associated with the tube, it can do them faster, more cheaply, and more reliably. Moreover, it occupies an infinitesimally small amount of space and, unlike the tube, requires no power-wasting filament that ties large equipment to the commercial power lines.

The dramatic effects of these advantages are most readily evident in the field of computers. The most advanced computer in the vacuum-tube era cost millions of preinflation dollars; consisted of an entire roomful of equipment utilizing tens of thousands of vacuum tubes; required a power plant...