Hopalong Cassidy is filling in for vacationing disc jockey Roger Ribbit as Polly Wogg settles in behind her desk after completing her lunch-time shift. All is well at the swampy location of Froggy 98 (WFGY-FM), one of Central Pennsylvania's radio stations.

A slapped-together motorhome/office building structure in the back lot of an Altoona car dealership, Froggy's headquarters is barely noticeable among the rows of Pontiacs and Toyotas. But within its thin walls, amphibians abound and country music runs the show.

Although the station plays country music and is named after an animal, sweatshirts and business suits take the place of cowboy boots and Stetsons some might imagine. But the playful personality of the staff is best represented by the abundance of frog memorabilia in the small, modestly furnished offices. From wind-up toys to embroidered pillows, the enthusiasm of its listeners is evident.

"We like to think of ourselves as an amusement park on the radio," said Wogg, program and music director. "There's a lot of stations built around animals -- we just happen to be frogs."

With 10 Frog stations across the country, Froggy 98 isn't alone in the amphibious radio field. The first Frog was started in Utica, N.Y., in 1986 by Kerby Confer. It was followed by K-FROG in San Bernardino, Calif., said Carol Logan, Logan Broadcasting president.

Logan passed on her first opportunity to switch to the Frog format when she was at the helm of Harrisburg's WNNK-FM (Wink 104).

"I couldn't imagine going from a kick-ass radio station to a frog," Logan said.

After purchasing WFBG-FM in Altoona, Logan said she gave Confer and his frog ideas another shot.

When the station switched to Froggy 98, Wogg was taken aback about having to change her name and insert swamp sounds during broadcasts while wishing people a "Hoppy Birthday." Now, she said, it is just second nature at the station that grabs more than 20 percent of the age 12 and older local rating share at any time of the day.

"It's more funny to me now than anything," she said, gesturing to the hundreds of frog-emblazoned items given to the station by its avid listeners. "People are just totally into this radio station -- there's surgeons that say they don't want to operate without Froggy on."

The station is celebrating its fourth anniversary Saturday. And it's popularity has warranted a second frequency in State College. Logan added 94.5 to make up for the 98.1 frequency's tendency to get distorted in the surrounding mountains.

But Froggy's rising success isn't worrying the owner of WZWW-FM (95.3). Dan Barker said all radio stations target specific audiences and Froggy's average listener is much younger than his contemporary music format's demographic.

"Every radio station is a competitor with every other radio station in terms of ears, but you have to look at how old those ears are," Barker said. "In my demographic, what I care about, they're not No. 1 -- my next closest competitor is in Williamsport."

With DJs such as Pete Moss, Ann Phibian and Webb Foot spinning the likes of Garth Brooks and Sawyer Brown, Froggy 98 has filled a country-music void in Western Pennsylvania and jumped onto country's rising popularity.

Froggy is a strictly contemporary-country station, playing nothing older than 1980, Wogg said, adding that there is a large difference between the sound of new and old country music. Citing the 1980 film Urban Cowboy as country's low point, Wogg said Randy Travis provided the necessary turnaround.

The appeal of country music has continued to grow because artists are incorporating elements of the mainstream music they grew up on with the traditional country sound, Wogg added, mentioning Travis Tritt's Southern rock roots as an example.

Country has also lost its uncouth rural image, Logan added.

"It's gotten rid of a lot of that yee-ha," Logan said. "It's kind of like going back to the roots of rock 'n' roll."

Along with infrequent commercials and 10-song marathons, Mark Cain, a Howard resident who listens exclusively to country and Southern gospel music, said he likes Froggy's community involvement.

"I like the fact that they try and help the businesses in the area," Cain said, referring to the station's on-location live broadcasts.

But one student said Froggy 98 is just too much country for her.

"I enjoy country music but 24 hours a day is a little much," said Melissa Gates (junior-biology).

Froggy 98 is not alone in the country music market. Bellefonte's WBLF-AM (970 AM) made the switch to country two years ago and has seen a considerable increase in ratings, said Dee Clark, owner, operations manager and program director of the 1,000 watt station.

WBLF may not be much competition for the 30,000 watt Froggy, but the revitalized sound of country has opened it up for everyone, Clark said.

"I think country's changed; it's not that hillbilly-out-in-the-barn sound anymore," she said. "We both have our niche in this market and there's plenty of room."

In addition to its mild-mannered DJs slinging the songs of Tanya Tucker and Alan Jackson, Froggy's promotions are almost as well known as its namesake.

As the only radio station in the nation to sponsor its own professional rodeo, Froggy has become an inseparable part of the community, whether it's the aptly named mascot Mr. Froggy showing up at shopping malls or its yellow bumper stickers plastered on sedans and pick-ups from Lewistown to Clearfield.

The laid-back and fun-loving personality of Froggy 98, as well as its music, appeals to one student listener.

"I like the attitude of the announcers -- they actually remember some of the people that call in," said Marvin Snider (junior-computer science). "I can understand the lyrics and they don't talk about going out and shooting a cop."

Regarding the Frog format of the station, Snider said it serves its purpose well.

"It's just a way of distinguishing them from anybody else," he said. "It's a lot easier remembering Froggy than any other station with letters in front of it."