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He Labored to Help Us Out of That Jam


The first SigAlert was declared 45 years ago on Labor Day 1955--and the backup that inspired it may be just about clear.

Traffic reporting in 1950s Los Angeles involved radio stations constantly monitoring police frequencies for crashes or mishaps, or randomly calling the LAPD in hopes of catching an incident, or even asking police dispatchers to call in whenever something came up. Good luck.

Then came Loyd Sigmon, a local radio executive who devised a system to make it easy for the police to alert stations. The system gave each radio station a special receiver tuned to a specific frequency and attached to a tape recorder. A dispatcher at LAPD headquarters could press one button to activate all the machines and announce the nature of the problem. The stations then either replayed or restated the message to warn the public.

A case of a man devoting his talents and expertise to the greater common good? Sort of. "What I had in mind was to get more listeners for KMPC, to be honest with you," said Sigmon, 92, who now lives far from the mechanized madness, having retired to northeastern Oklahoma in May after living in Sherman Oaks since 1946. "The air is clean, the traffic is good," added Sigmon, who has given up driving his Lincoln Continental with the "SIGALRT" vanity plate.

Sigmon, a co-owner of KMPC-AM (710) at the time of his invention, didn't get the one-up on his competitors that he had hoped. Los Angeles Police Chief William Parker didn't want to play favorites. "He knew me very well," Sigmon said. "He said, 'Sig, you can't have this system all to yourself. You have to make it available to everybody.' " But Parker did give credit where it was due, coining the term SigAlert.

When the LAPD broadcast the first SigAlert on Sept. 5, 1955, the announcement caused even more trouble than the accident that had precipitated it. A train en route from Union Station to Long Beach had derailed downtown, rolling onto its side. When the LAPD sent out a plea for doctors and nurses in the area through the new system, so many responded that they created a traffic jam themselves.

The early SigAlerts warned residents of more than just traffic jams--there were rabid-dog reports, a warning about the impending collapse of the Baldwin Hills Dam in 1963, and a potentially fatal case of a druggist mistakenly giving out the wrong prescription. One even announced the collision of two ships in Los Angeles Harbor.

That was enough for Parker. "We're not going to run the traffic for the harbor," he said.

The California Highway Patrol took over responsibility for the freeways in 1969, and with that the SigAlert system as well. And though most radio stations now get information about SigAlerts from the CHP Web site (, the name has remained--striking terror and dread in L.A. drivers.


Like first-graders on a playground, they know it's a bad word, but probably aren't exactly sure what it means. Unlike its wide-ranging early days, a SigAlert now designates only any unscheduled freeway problem that closes one or more traffic lanes for at least 30 minutes.

Traffic alerts exist in all major cities, said Matt Roth, archivist for the Automobile Club of Southern California. It's just that the Los Angeles media have popularized the term for home-grown troubles.

In 1994, SigAlert became an entry in the Oxford English Dictionary, so motorists nationwide know what it is, even if they've never been caught in the Orange Crush or stuck in Grapevine traffic after a holiday weekend. And last year Arizona State University's art museum sponsored an exhibition called 'Sig-alert." Of the L.A. artists featured in the show, it said, "Instead of waiting in traffic, they find new routes around the roadblocks of the art world." The show also appeared at Cal State Fullerton.

But while L.A. will always have traffic tie-ups, it almost didn't have Sigmon. In 1941, he was working as an engineer in Kansas City, Mo., at a station owned by MacMillan Petroleum Co., which asked him to move to its station, KMPC, in Los Angeles. He told them he had no interest in leaving Kansas City.

So they offered him a free trip, just to see what he thought. "They gave me a convertible and put me up at the Beverly Wilshire Hotel--I'm just about 30--then they took me to the Brown Derby with all the movie stars. I swallowed--hook, line and sinker."

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