The southern California man who published the radio scanning bible Police Call has passed away. Under the pen name Gene Hughes, Gene Costin became a household word among geeks in the 1970s when he started cataloging the radio frequencies used by various police and fire departments and other agencies, giving hobbyists something to do with the first generation of programmable scanners then hitting the market. I had the privilege of interviewing him for a profile in 2005, when he made the decision to close down Police Call after 41 years.

It was the best day amid the worst years of Gene Hughes' life. He was 13 years old and seeking escape from the loneliness of a Los Angeles foster home by playing with an AM radio his uncle had mailed him. Tuning around the dial, he picked up something different from the dance hall music and campy radio dramas that normally spilled from the tinny speaker -- something unexpectedly genuine. "I suddenly heard strange voices, women broadcasting addresses and numeric codes," he recalls.

He quickly figured out that he'd somehow tuned into Los Angeles Police Department dispatchers crisply directing the city's black-and-white police cars to real robberies, domestic disturbances and traffic accidents throughout the City of Angels.

That was 1940, nearly a half-century before shows like Cops would turn live police action into mass entertainment. And what might have sounded to someone else's ears like unwanted interference from a city transmitter, was to Hughes the pulsing music of an invisible world. He bought a map and started marking out the police calls with a pencil. As he moved into adulthood, his interest only increased, and he invested in specialized radio receivers. "If they had the word, I guess you'd have called me a nerd," says Hughes.

But that nerdiness paid off. In 1964, in a bet with his wife, Hughes took all the information he'd accumulated -- call signs, frequencies and codes for police, fire, paramedics and other agencies -- and rolled it up into a 16-page manual titled Police Call.

It was the start of something big. Under Hughes' direction, Police Call would eventually expand into nine regional volumes covering the entire continental United States, with a peak circulation of a half-million copies. Updated annually, it would sell countless thousands of radio scanners and play a crucial role in incubating and growing the hobby of radio monitoring, which traces a line from the cop watchers of the 1970s to the railfans of the '90s and the NASCAR dads of today.

Along the way, Police Call would help spawn local and national clubs and organizations, spark brushfire controversies over information disclosure, and turn Gene Hughes -- a pen name -- into a household word among scanner buffs and anyone who spent too much time at Radio Shack when they were kids.

Scanner buffs are posting memories to Costin's online tribute page.