In 1927, the late electrical engineer Harold S. Black (1898-1983) formerly of Summit, was on a ferry heading toward his office in New York City when an idea that would change the course of electronic communications popped into his head. His idea was for a "negative feedback amplifier," whereby distortion is eliminated by feeding back part of the communication signal into the amplifier. At the time of his invention, Black worked at Western Electric's West Street Labs, New York City, the forerunner of Bell Telephone Laboratories.

Black sketched his idea on the only paper available to him then, a copy of The New York Times. He had been researching the solution to distortion in amplified sound for almost four years before this breakthrough. It was probably the most significant patent of some 347 patents granted to him.

Early in his career, Black was assigned the task of reducing amplifier distortion so that a large number of multichannel amplifiers could be hooked up in random to carry telephone calls over longer distances. The job required an amplifier superior to any then existing. Many other researchers before Black were aware of this need. On that fateful morning in 1927, Black realized that by utilizing negative feedback, he could obtain a desired reduction in distortion at the expense of a sacrifice in amplification.

The theory was first used to improve long-distance telephone service, and has recently been applied to fields such as biomechanics, bioengineering, digital computers, artificial limbs for the disabled, automatic controls for wheel chairs, and high fidelity sound reproduction. Many new weapons systems, such as radar-directed bombing and radar-controlled missiles, depend on negative feedback for their success.

Throughout his lifetime, Black was also a literary critic, teacher and lecturer. During World War II, Black was the first to produce pulse modulation and designed pulse code modulation multichannel microwave radio relay
systems, which today are widely used for military and domestic uses.

Black graduated from Worcester Polytechnic Institute, Worcester, MA in 1921 and received an honorary doctorate in engineering from Worcester Polytechnic Institute. Born in 1898 in Leominster, MA, Black adapted his negative feedback system to aid the blind and deaf from 1966 until his death.

Black was inducted into the National Inventors Hall of Fame, Akron, OH, in 1981. He was awarded the Worcester Polytechnic Institute's highest honor, the Robert H. Goddard Award in 1981 for recognition of outstanding professional achievements. He also received 10 medals, 11 fellowships, nine awards and numerous honors. Black wrote Modulation Theory, published in 1953.