Although new inventions are made so rapidly in the electronics field as to be considered almost "every-day" occurrences, few are truly revolutionary in scope. The development of a new vacuum tube, transformer, or capacitor, important as it may be to one branch of the field, generally has little over-all affect on the industry.

But revolutionary inventions are occasionally made... one such development was the invention of the triode vacuum tube by DeForest. It is reasonably safe to say that the present-day radio, television and electronics industry has resulted from the applications of this one invention and its modifications. And the invention of the transistor by Shockley, Bardeen andBrattain of the Bell Telephone Laboratories may be as revolutionary and have as far-reaching effects as the invention of the triode vacuum tube. For the transistor is capable not only of doing most of the things that vacuum tubes do but can also perform jobs which have heretofore been difficult, if not impossible, for vacuum tubes alone to handle.

The transistor may be used as an oscillator, as an a.c. amplifier, as a d.c. amplifier, as a relay or electronic switch, as a mixer or modulator, and as a detector. It may also be used as an attenuator, for impedance matching, and as an isolation or "buffer" amplifier. But even with its amazing versatility, the transistor is at one time much smaller, lighter, longer lived, more rugged, fantastically more efficient and potentially less costly than the vacuum tube. And the transistor offers the additional advantage of instant operation .... no "warm-up" time is required nor is "standy-by" power needed for its operation. From this it is easy to see that virtually every worker in the electronics field will eventually come into contact with the transistor, even if only indirectly.

The serviceman may expect a gradual introduction of the transistor in equipment he is called on to repair and maintain. Starting with hearing aids, portable record players and radios, electronic megaphones and similar equipment, he may expect to see the transistor eventually used in home broadcast receivers, auto radios, headlight 'dimmers", television sets, recorders, and inter-communication equipment.

The ham will find many applications of the transistor in portable and mobile equipment, in small receivers, in transmitters, and in portable test and measuring equipment.

The electronics engineer will find that he is not only required to design new equipment using transistors but that he will be frequently called on to redesign existing equipment to make use of the advantages offered by transistor operation.... that is, to "transistorize" vacuum tube equipment.

The experimenter will find the transistor ideally suited to the design of gadgets, electronic toys, and experimental circuits. The fantastically small power requirements of transistor circuits make them ideal for portable equipment, while their light weight and small size suit them for use in remote control circuits.

The radio operator will find that a knowledge of transistor circuitry will be useful in understanding the functioning of transistorized equipment he is called on to operate and to adjust. And the student will find that an understanding of transistor operation is as important as a knowledge of vacuum tube operation if a well rounded and up-to-date education in the electronics field is to be acquired.

The military uses of the transistor are obvious, although no details have been officially released at this writing... the transistor is potentially suited for use in guided missiles, proximity fuses, portable radio and radar equipment, remote controlled devices, miniature teletype and communication equipment, miniature television "spy" apparatus, radiation detection and measuring instruments, "Secret Agent" radio transmitters and receivers, air-sea rescue radio equipment, compact artillery computers, detonating devices, etc... in short, wherever light weight, small size and economy of operation are desirable in electronic equipment.

Commercially, the transistor promises to revolutionize the design of many types of equipment. Giant electronic "brains" or computers may be reduced to table-top size... in fact, miniature all-electronic calculaters and adding machines for routine office work may soon become a reality. Hundreds of thousands (if not millions) of transistors may eventually be used in telephone circuits alone, performing dialing, switching, signaling, routing, relaying, amplifying, and control opertions.

But these potential applications of the transistor are but a sample of what the future may bring. It must be remembered that the transistor is a comparatively new invention... compared to the vacuum tube, the transistor is but a mere babe-in-arms.

The following chronology, prepared by the Bell Telephone Laboratories, gives a glance backward over the history of transistor development, and illustrates, in concise form, the rapidity with which one transistor development has followed another...

JUNE, 1948 -- The point-contact transistor made its first public appearance at the West Street headquarters of Bell Laboratories in New York. It had been demonstrated privately to the military a short time before this announcement to the press.

MARCH, 1950 -- Invention of the photo-transistor by the (Bell Telephone) Laboratories1 Dr. J.N.Shive was announced. An entirely new type of "electric eye" -- much smaller and sturdier than present photo-electric cells and possibly cheaper --it is a transistor controlled by light rather than by electric current.

JULY, 1951 -- The junction transistor, a radically new and in many ways more effective type, invented by Dr. Shockley, was announced. Morgan Sparks built the first of the new type transistors, using crystal processes developed by G.K. Teal and J. B. Little. Among others, R.L. Wallace, Jr., and W.J. Pietenpol worked on their development The junction transistor was described as "extremely small, occupying only about 1/400 of a cubic inch" and even less power-consuming than the original point-contact type.

The (Bell Telephone) Laboratories also announced that development work on the point-contact type had resulted in understanding problems involved in reliability and reproducibility, thus bringing regular production nearer.

SEPTEMBER, 1951 --A transistor symposium held at Murray Hill. Nearly 3 00 guests attended the sessions; represented were industry, the Army, Navy, Air Force, government agencies and their contractors, and several universities.

OCTOBER, 1951 -- Production of the first transistors begun by the manufacturing department of Western Electric at its Allentown plant.

APRIL, 1952 -- Transistor technology symposium held at Murray Hill and Allentown, Pa. This was concerned with the development of transistors, phototransistors and related semiconductor devices.

JUNE, 1952 -- Sixty-three faculty members, representing 33 universities, colleges, and institutions of technology attended the first transistor school, sponsored by the Laboratories (Bell Telephone) and held at Murray Hill, N.J. The school was designed to facilitate the introduction of transistor physics into university courses.

AUGUST, 1952 -- First announcement of a "tetrode" transistor, invented at Bell Laboratories by R.L. Wallace, Jr. By adding a fourth electrode, Wallace was able to produce a transistor usable at frequencies at least ten timles higher than would otherwise be possible.

OCTOBER, 1952 --The transistor went to work for the first time in the nation's telephone network. Oscillators employing transistor units were installed in dial switching equipment in Englewood, N. J., as part of the customer long distance dialing trial. The first commercial oscillator model was assembled in the (Bell Telephone)Laboratories by F.E. Blount, assisted by D. Houk.

END OF 1952 -- First over-the-counter consumer product to make use of transistors was put on the market by manufacturers of hearing aids.

MARCH, 1953 -- A most important use of the transistor was made public when the (Bell Telephone) Laboratories announced development of the "card translator," which will serve as an automatic routing device for setting up long distance calls across the country. The card translator makes use of both the phototransistor and the current-amplifying transistor.

As for the future of the transistor... one engineer has said - "Within a few years... five to ten at the most... we may expect to see more transistors than vacuum tubes used in new equipment!"

Source:
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