For Kids’ Ears, Mostly : Radio Disney says that its 5-week-old L.A. outlet on KTZN-AM is already a solid success.

The Radio Disney children’s network has been on the air at KTZN-AM (710) for more than five weeks and, according to Maureen Lesourd, the station’s president and general manager, reaction has been good.

Sure, she’s gotten complaints about the departure of the Zone--the female-oriented talk programming that the station previously featured--but she says it’s been offset by positive response to the new format, particularly from children.

Lesourd says Radio Disney has been getting 28,000 calls a day from Southern California kids. Children phone an 800 number at Radio Disney headquarters in Dallas to request songs, participate in quizzes and contests, tell jokes and talk to other children on the air.

Considering that Arbitron, the radio ratings service, counts only listeners who are 12 and older, such calls are seen by Radio Disney as a key indicator of audience growth. So too does the forerunner in the children’s field, Children’s Broadcasting Corp., which operates the Aahs World Radio network.

As radio mavens know, children’s programming is the new kid on the radio block. “I think our industry finally realized,” says Lesourd, “that there’s a market out there. Kids know a lot about products and what they like.”

The preteen advertising market--which children’s TV has tapped for decades--is estimated at $1.5 billion. “Kids make up almost 20% of the country,” explains Scott McCarthy, vice president and general manager of Radio Disney. “If you put on good programming, market and promote properly and have a good signal, listening will follow.”

Radio for children on a national scale essentially began in October 1992, with the 24-hour Aahs service. It is now heard on 29 stations, 10 of them owned by Children’s Broadcasting, including Anaheim-based KPLS-AM (830). Although the company is selling its stations to Global Broadcasting for $72.5 million--and there’s uncertainly as to whether the 10 will stay with the children’s format after the deal closes in January--Children’s Broadcasting will continue as a syndicator.

Radio Disney entered the field on Nov. 18, 1996--Mickey Mouse’s birthday--starting on four stations, then adding a Seattle outlet and KTZN, which is owned by ABC Radio, a division of the Walt Disney Co. “We expect to add about 25 stations a year,” McCarthy said, and eventually to be in “the top 75 markets.”

Radio Disney’s launch provoked a federal lawsuit by Children’s Broadcasting, alleging that ABC Radio, which had served as its national advertising representative, used confidential information to start its own network. ABC has denied the charge and calls the lawsuit unfounded.

One thing both companies agree on, however, is that they can prove that children are listening--even without Arbitron.

Joy Plaschko, media relations manager at Children’s Broadcasting, says their phone system logs nearly 3 million calls a year and “when we have events, thousands of kids show up. Our Web site has an incredible number of hits.”

Radio Disney conducted extensive research on its four test stations during the first three months of the year. Statistical Research Inc. found that 78% of the surveyed children between the ages 5 and 9 said they had listened to radio the day before.

Other research shows that most children listen to the radio in cars, which means an adult is with them. That’s why a lot of the advertising heard on Radio Disney is aimed at adults: supermarkets, cars, home loans.

Not surprisingly, some of the advertising also comes from the Disney conglomerate: the Saturday-morning cartoons on ABC; the Buena Vista home video, “Honey, I Shrunk the Kids.”

Lest you think that’s too Disney, KTZN points out that it will soon be airing ads for the Fox video “Casper.”

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Not Kids’ Stuff: To mark the 50th anniversary of the notorious House Un-American Activities Committee hearings that resulted in the Hollywood blacklist, KCRW-FM (89.9) is airing a series of broadcasts about that period on “KCRW Playhouse,” beginning at 6 p.m. Sunday and running through Oct. 26.

The opening presentation, “Brecht in Hollywood,” profiles German playwright Bertolt Brecht’s years as an emigre here from 1941 to 1947, including his testimony before the committee. It first aired on Pacifica Radio in 1963 and was produced by David Ossman, Bill Malloch and Ruth Seymour, better known these days as KCRW’s general manager.

Other offerings this month are the six episodes of Tony Kahn’s 1995 radio series, “Blacklisted”; “The Waldorf Conference,” about a meeting of Hollywood executives that led to the creation of the blacklist, by Nat Segaloff, Daniel M. Kimmel and Arnie Reisman; and “Are You Now or Have You Ever Been,” Eric Bentley’s 1988 re-creation of the hearings. Fifty years ago, “Are you now or have you ever been . . . "--asking about Communist Party membership--became the signature phrase of that era in America’s history.

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Welcome, Hosts: KCSN-FM (88.5), the classical music station at Cal State Northridge, has two new weekday hosts. Mara Zhelutka is on 10 a.m. to 2 p.m and Teresa Payerle has the 2 to 6 p.m. shift, essentially replacing Bonnie Grice, who left in June.

Both women are familiar to Southern California listeners. Zhelutka is heard Sunday mornings at 6 on KCRW with “Music of the Spheres,” which explores medieval, renaissance and baroque music.

Payerle, who was a staff announcer and operations manager at KKGO-FM (105.1), has also programmed and hosted the morning drive slot at KUSC and was a traffic reporter at KFWB-AM (980).

“They bring a wealth of experience to the station,” said Rene Engel, KCSN general manager, “and they have been very welcome hosts in Los Angeles.”