Texas Instruments
In 1930, J. Clarence Karcher and Eugene McDermott founded Geophysical Service, an early provider of seismic exploration services to the petroleum industry. In 1939, the company reorganized as Coronado Corp., an oil company with Geophysical Service Inc (GSI), now as a subsidiary. On December 6, 1941, McDermott along with three other GSI employees, J. Erik Jonsson, Cecil H. Green, and H.B. Peacock purchased GSI. During World War II, GSI expanded their services to include electronics for the U.S. Army, Signal Corps, and the U.S. Navy. In 1951, the company changed its name to Texas Instruments, with GSI becoming a wholly owned subsidiary of the new company.
Transistor radio
There are many claimants to the title of the first company to produce practical transistor radios, often incorrectly attributed to Sony (originally Tokyo Telecommunications Engineering Corporation). Texas Instruments had demonstrated all-transistor AM (amplitude modulation) radios as early as May 25, 1954, but their performance was well below that of equivalent vacuum tube models. A workable all-transistor radio was demonstrated in August 1953 at the Düsseldorf Radio Fair by the German firm Intermetall. It was built with four of Intermetall's hand-made transistors, based upon the 1948 invention of the "Transistron"-germanium point-contact transistor by Herbert Mataré and Heinrich Welker. However, as with the early Texas Instruments units (and others) only prototypes were ever built; it was never put into commercial production. RCA had demonstrated a prototype transistor radio as early as 1952, and it is likely that they and the other radio makers were planning transistor radios of their own, but Texas Instruments and Regency Division of I.D.E.A., were the first to offer a production model starting in October 1954.
The use of transistors instead of vacuum tubes as the amplifier elements meant that the device was much smaller, required far less power to operate than a tube radio, and was more shock-resistant. Since the transistor base draws current, its input impedance is low in contrast to the high input impedance of the vacuum tubes. It also allowed "instant-on" operation, since there were no filaments to heat up. The typical portable tube radio of the fifties was about the size and weight of a lunchbox, and contained several heavy, non-rechargeable batteries— one or more so-called "A" batteries to heat the tube filaments and a large 45- to 90-volt "B" battery to power the signal circuits. By comparison, the transistor radio could fit in a pocket and weighed half a pound or less, and was powered by standard flashlight batteries or a single compact 9-volt battery. The now-familiar 9-volt battery was introduced for powering transistor radios.