In a field where components and systems are often known by sterile strings of characters that manufacturers assign or by cutesy names that are clearly products of the marketing department and their focus groups, having your name attached to an innovation is rare. Rarer still is the case where the mere mention of an otherwise obscure inventor’s name brings up a complete schematic in the listener’s mind.
Given how rarely such an honor is bestowed, we’d be forgiven to think that Sidney Darlington’s only contribution to electronics is the paired transistor he invented in the 1950s that bears his name to this day. His long career yielded so much more, from network synthesis theory to rocket guidance systems that would eventually take us to the Moon. The irony is that the Darlington pair that made his name known to generations of engineers and hobbyists was almost an afterthought, developed after a weekend of tinkering.
A Passion for Networks
With her background as a teacher in a one-room schoolhouse on the edge of the American prairie, Sidney Darlington’s mother was determined that her children would have the best educations possible. His father, a mechanical engineer, was likely an influence on Sidney and his brother Philip, both of whom embarked on scientific careers. Philip chose biology while Sidney chose physics, which he studied at Harvard. After graduating in 1928, he earned a second B.S. in electrical engineering the following year from MIT.
Having been instilled with a passion for circuit analysis by his professors, in 1929 Sidney went to work at Bell Laboratories, then the center of the electrical engineering universe. He quickly found his way to the lab’s Mathematics Research Center, where his interest in circuit analysis would prove key to designing the complex filter networks needed to support the nascent technology of multiplexing, which can be used to stuff multiple telephone signals through one cable.
At the time, filter design was largely a trial and error affair where different filtering stages were connected together to achieve the desired result. This was inefficient from a design standpoint, and the filters often ended up not behaving quite as intended due to loading introduced by the various stages. Darlington’s method of filter design, known as network synthesis, took these impedances into account from the start, resulting in better filters and better networks.
Having already established a name for himself as well as a legacy, and with World War II in the offing, Darlington turned his work toward military needs. His theoretical bent and gift for mathematics made the problems involved with putting munitions on target an interesting one, and Darlington ended up making significant contributions to both bombsight designs and fire control systems for artillery. Near the end of the war he took a leave of absence from Bell to join the 14th Antiaircraft Command in the South Pacific as a civilian advisor.
More Than The Sum
With the conclusion of the war and the ensuing rush to switch basic research from military goals to commercial …read more
Source:: Hackaday