History of hearing aids
The development of transistors in 1948 by Bell Laboratories led to major improvements to the hearing aid. The transistor was invented by John Bardeen, Walter Brattain, and William Shockley. Transistors were created to replace vacuum tubes; they were small, required less battery power and had less distortion and heat than their predecessor. These vacuum tubes were typically hot and fragile, so the transistor was the ideal replacement.The 1952 Sonotone 1010 used a transistor stage along with vacuum tubes, to extend battery life. The size of these transistors led to developments in miniature, carbon microphones. These microphones could be mounted on various items, even eyeglasses. In 1951, Raytheon manufactured the transistor and was one of the first companies to mass-produce transistors to throughout America. Raytheon realized that their hearing aid only lasted short-term and began to sell the vacuum-tube hearing aids again along with transistor hearing aids.
Grant O. Gale
From Bardeen, Gale acquired early versions of the transistor. One of Gale's most noted students was his former baby sitter, Robert Noyce, co-inventor of the integrated circuit and founder of Intel. While Noyce was his student at Grinnell:
Gale had kept up with Bardeen and his work, and he obtained two transistors in 1948 while Noyce was an undergraduate. Noyce worked with Gale on the transistor and was thus among the first to encounter its limitless potential.
Gale's mentorship of Noyce was also instrumental in protecting him from disciplinary action when Noyce stole a pig from a nearby farmer (who actually was also the Mayor) and then slaughtered it in Clark Hall for a college luau. The prank would have earned him expulsion and jail time since livestock theft was a felony offense in Iowa, if not for Gale's intervention. (The pig you refer to was actually slaughtered by Roger Barnes, a Hawaiian physics student in the fall of 1966. Mr. Barnes was encouraged and assisted by Richard Weeks of Palatine, Illinois and John Pittman of Lake Oswego, Oregon and elected by his housemates to prepare the feast. He was the only student who had any actual experience preparing a suckling pig for a luau. The festivities were halted when a maintenance man saw the pig hanging from the shower spigot and alerted the Dean of Men. The Dean surprised the assisting group of students who were just on a "study break" and ordered them to stop immediately. They were directed to take the carcass to the Saga Foods Dining Hall where it could be properly disposed of. The partially shaved and scrubbed pig may not have reached its intended destination and actually ended up at Clark Hall, the dormitory adjacent to the Dining Room. Thankfully. It was a cold night.)