HALL OF FAME / inventor profile


Herman Andrew Affel
Born August 4 1893 – Died October 13 1972

Concentric Conduction System
Patent No. 1,835,031

Inducted 2006

Herman Affel and Lloyd Espenschied invented coaxial cable at AT&T Bell Telephone Laboratories in 1929. The coaxial cable opened a wide spectrum of frequencies for long distance telephone service, making it possible to carry thousands of simultaneous phone calls on long distance circuits.

Invention Impact

Broadband coaxial cable created a higher capacity for local and long distance circuits. During his career at Bell Labs, Affel
worked with other engineers to combine coaxial cable with microwave relays, making high-volume transcontinental telephone and
television transmission signals possible. He earned several other patents for electronic devices, including advanced
transmitters and innovative antennas.

Inventors Bio

Affel was born in Brooklyn, New York and studied electrical engineering at the Massachusetts Institute of Technology. As a
consultant to Bell Labs, Affel worked with Espenschied devising efficient means to carry high frequencies needed for broadband communications systems. Affel and Espenschied created a transmission system using a coaxial conductor, consisting of two concentric cylinders of conducting material separated by air. This structure reduced frequency losses and prevented outside interference.



© 2002 National Inventors Hall of Fame