Loyd Sigmon

Lore & Background

Sigmon earned his amateur radio license at age 14 and began his broadcasting career in 1932 at the Boston Short Wave and Television Laboratories. In 1941 he became an engineer for KMPC, the flagship station of MacMillan Petroleum Company in Los Angeles. His work was interrupted by World War II, during which he served in the United States Army Signal Corps on General Dwight D. Eisenhower's staff. After the war, he returned to Los Angeles and rose to Executive Vice President of Gene Autry's Golden West Broadcasters, which owned eight radio and two television stations on the west coast, including KMPC. In 1955, Sigmon invented a specialized radio and tape recorder that the Los Angeles Police Department used to alert radio stations to traffic conditions and emergencies. The messages were called 'Sigmon traffic alerts,' soon shortened to 'Sig Alert.' The system was later employed throughout California and copied in numerous other areas. Sigmon kept his amateur radio license, W6LQ, current even after retiring to Oklahoma.

Reader's Guide

Loyd Sigmon's most enduring contribution is the Sig Alert, a traffic alert system he invented in 1955 for the Los Angeles Police Department. The system used a specialized radio and tape recorder to broadcast traffic conditions and emergencies to radio stations, a method that became standard throughout California and was adopted in many other regions. Bill Keene called Sigmon the 'father of L.A. traffic reporting.' Sigmon received recognition from local and state government agencies, the National Safety Council, and broadcasting and radio organizations. In 1998, when the California Department of Transportation and the California Highway Patrol opened their Freeway Traffic Center in Los Angeles, Sigmon attended as their special Guest of Honor. He was quoted in the Los Angeles Times as saying, 'I ran a multimillion-dollar corporation, but it's the Sig Alert that people remember me for.' His invention fundamentally changed how traffic information was disseminated to the public, and his legacy is tied directly to the daily traffic reports heard by millions.

Did You Know?

• He invented the Sig Alert system in 1955 for the Los Angeles Police Department.
• His amateur radio callsign was W6LQ.