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.
Reading Works
In 1951, just four years after the invention of the transistor by Bell Laboratories, the Allentown Plant was opened to manufacture the first transistors. Jack Morton was assigned to develop transistors for manufacture. He had been responsible for inventing and providing the military with microwave components during WWII and knew how to get an idea from the lab, into production, and into the field. He established a system of branch labs at several Western Electric plants, consisting of teams of Bell Labs scientists and engineers focused on production engineering and acting as liaison with their colleagues back in Murray Hill. Morton fine-tuned this approach at the new Western Electric plant in Allentown, Pa., which produced electronic devices and components for the Bell System. He set up a Bell Labs semiconductor development group there and put Eugene Anderson in charge.