Each hour, KPFK radio has 57 minutes and 30 seconds of available airtime. For the past decade, Jon Wiener has helped fill them with stimulating content.

Wiener, UC Irvine history professor and host of “The 4 O’Clock Report” on KPFK 90.7 FM in Los Angeles, has a unique appreciation for the medium and its ability to both entertain and inform.

After all, he has commuted 55 miles from his home in West Los Angeles to UCI – and back – for more than 25 years. “I listen to the radio the whole time,” he says.

Wiener began appearing on KPFK as an occasional guest when The Nation magazine launched a show at the station in the late 1990s. Wiener was a natural fit because he wrote for the weekly politics-and-culture magazine and lived locally.

He then guest-hosted when Marc Cooper, The Nation’s contributing editor who also ran the radio program, was out of town on assignment.

The station management liked Wiener’s work and offered him his own show starting in mid-1999. Wiener, an avid radio listener, jumped at the opportunity.

Almost 10 years later, he enjoys the work as much as ever.

“I get to talk to terrifically interesting people,” Wiener says of his public affairs interview program.

“Radio seems to be understood as the best place today to sell books, so virtually all authors want to be on the radio – or at least their publicists tell them they ought to be,” he says. “I’m able to get Pulitzer Prize winners, National Book Award winners and New York Times columnists. That’s a real thrill.”

Wiener lists NPR’s Terry Gross, celebrated public radio host Ira Glass, comedian and politician Al Franken, and author and radio personality Garrison Keillor among his favorite guests.

Dexter Filkins, New York Times Baghdad correspondent, and Jane Mayer of The New Yorker have provided some of Wiener’s favorite journalist interviews.

Wiener spends each Wednesday from 8 a.m. to 2 p.m. preparing for the day’s show. He researches his guests by reading as much of their books as possible.

“Sometimes all the reading makes me feel like an undergraduate again,” he says with a laugh.

Wiener’s background as a historian and ability to provide context to current events have helped him carve a niche with listeners. Passionate about his roles as both a university professor and a radio host, he sees his radio gig – in some ways – as the “opposite of teaching.”

“On the radio, I’m supposed to be opinionated and assertive,” Wiener says. “But I see the classroom as an open place for considering conflicting views and giving students the chance to talk.”

Wiener’s show airs 4-5 p.m. Wednesdays. It streams live and also is archived on the KPFK Web site.