Sig Alert - The Origin of The Sigmon Traffic Alerts

The Origin of The Sigmon Traffic Alerts

SigAlerts originated in 1955 with the Los Angeles Police Department (LAPD). By the early 1950s, the rapidly growing number of automobiles in Los Angeles had greatly increased the frequency and severity of traffic accidents and jams. Radio stations reported traffic conditions, but the LAPD refused to call radio stations with this information, so each station would call the LAPD, a process that tied up telephone lines and forced officers to repeat the same information again and again.

In 1955, Loyd C. "Sig" Sigmon began developing a solution. Sigmon was Executive Vice President of Golden West Broadcasters (a company owned by singing cowboy Gene Autry). Sigmon had worked for Golden West's station KMPC 710 in 1941, but found himself in the United States Army Signal Corps during World War II, assigned to General Dwight D. Eisenhower's staff, in charge of non-combat radio communications in the European theater. Now, he proposed to apply his knowledge of complex radio networks to the situation in Los Angeles.

Sigmon developed a specialized radio receiver and reel-to-reel tape recorder. When the receiver picked up a particular tone, it would record the subsequent bulletin. The device cost about $600. The LAPD's chief, William H. Parker, was interested, though skeptical, warning the inventor, "We're going to name this damn thing Sigalert." More practically, he refused to use it unless the receivers were made available to all Los Angeles radio stations — it could not be a KMPC monopoly.

Initially, half a dozen stations installed Sigmon receivers that had "Sigalert" stamped on their side. When a message had been received and recorded from the LAPD, a red light, sometimes accompanied by a buzzer, would alert the radio stations' engineers. Depending on the nature of the problem, the engineer could air the police broadcast immediately, interrupting regular programming if necessary.