The humble but iconic SigAlert to be feted today

sigmon-portrait2.gifThis morning at 9 a.m., Councilman Tom LaBonge and others will gather at the Caltrans building in Downtown to celebrate the first use of Loyd Sigman's SigAlert system. The original SigAlert went out on Jan. 21, 1955, not to alert drivers to traffic snarls, but to summon doctors to a horrible train wreck where Washington Boulevard crosses the Los Angeles River. From a City News Service story on the Daily News website:

Sigmon was a vice president at Gene Autry's KMPC, which in the pre-wired world of the 1950s revolutionized Southern California driving by launching a fleet of airplanes and helicopters to cover traffic during rush hours. But the "KMPC Air Force" could not fly day and night, and Sigmon wanted LAPD officers to phone KMPC when freeways or streets were clogged....

According to radio historian Harry Marnell, a SigAlert could be triggered by a watch sergeant at LAPD headquarters if he pressed a button to generate the tone on the LAPD radio system. At 11 commercial AM radio stations in L.A., Sigmon's technology would prompt then-new reel-to-reel tape recorders to start up, and would flash lights or buzzers.

The news staff or announcers could then relay the breaking traffic news to the listeners. Chief William Parker approved the idea, but only if KMPC's competitors could also share the technology.

These days the CHP declares a SigAlert for any unplanned freeway lane closure expected to last more than 30 minutes. This morning's public ceremony begins at 9 a.m., LaBonge says, "unless there is a big SigAlert,"

Current CHP incidents

From 2004:
Loyd Sigmon, L.A. traffic icon was 95 *

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