WASHINGTON – The typical listener is probably a male (but might be a female), most likely under 30 (but might be over), and is almost certainly listening in a house (but might be in a car). When it comes to knowing its audience, the American-funded Radio Farda knows only two things for sure: that the audience is surreptitiously listening somewhere inside Iran, and that the Iranian government doesn’t want anyone to hear what an American-funded radio service has to say.

How, then, does Radio Farda – which receives about $7 million in federal funding and is hoping for substantially more as America expands its push for democracy in Iran – decide what to broadcast?

The answer can be found in an anonymous office building off Interstate 95 in Northern Virginia. There, past the guard, past the magnetometer, through the controlled-access doors, and at the very far desk in a quiet room, Sara Valinejad is about to click a computer mouse and determine what any Iranian with an AM or shortwave radio, or an Internet connection, will be able to hear the following day.

“In Iran, they don’t allow you to be happy,” Ms. Valinejad, 30, who emigrated from Iran 10 years ago, said. Radio Farda, she said, is intended to do the opposite. “It puts you in a good mood when you listen to this radio station.”

Click.

And so it is that in Iran they’ll soon be hearing “Hung Up” by Madonna.

From surveys of Iranian ex-pats to market tests in Dubai, Radio Farda has been a work in progress since its debut in late 2002. The one constant is that unlike Cold War-era transmissions by the Voice of America and Radio Free Europe that relied primarily on news programming, Farda blends news and music as a way to reach a country where two-thirds of the population is said to be under 30.

“A little bit of entertainment” is how a consultant to Radio Farda, Bert Kleinman, describes the broadcast formula he helped design. “The core of the mission is news and information” – in a typical hour, 16 1/2 minutes of programming is devoted to news – but “we were tasked to reach out to the younger generation there. And quite frankly, you just can’t do it with news.”

So in addition to a 10-member news staff in Washington and a 28-member news staff in Prague, there is Ms. Valinejad. As the person in charge of the non-news, she also sifts through some 300 phone messages a day from listeners responding to the interactive feature “What Do You Think?”

“We try in the American tradition to have respectful dialogue,” Mr. Kleinman said of this feature, which airs twice an hour. An acceptable topic, he said, is, “What should be done to improve the relationship between Iran and the United States?” An unacceptable topic would be, “Should the mullahs be overthrown?”

Station promotions air several times an hour, along with features about health issues (acceptable: “why vitamin E is good for you,” Mr. Kleinman said; unacceptable: “boil your water so you don’t get bubonic plague”).

More than anything else, though, there is music.

“Adult contemporary,” Mr. Kleinman said. Music with “a happy beat to it.”

No hip-hop. No alternative. No rap.

“Madonna. Michael Jackson. The Gipsy Kings. Bob Marley,” Ms. Valinejad said, looking over her playlist. “Abba. Enrique Iglesias. Phil Collins. Celine Dion.”

There are Persian singers, too, including Googoosh, Dariush, Siavash Ghomayshi, Mansour, Hayedeh, and Ebi.

“I know every single Persian singer,” Ms. Valinejad said, largely from watching the satellite feed of several Los Angeles-based TV stations that beam programming into the homes of Iran’s elites. The elites get TV and the masses get Farda.

Ms. Valinejad sorts the songs into categories such as West Gold (Eagles, Elton John, Michael Bolton) and Persian Gold (2 Fun, Andy, Sandy, Aref).

She enters the song lists, the chosen answers, the health tips, and promos into a computer program, and one click later everything is arranged into minute-by-minute programming for an entire day.

“It’s easy,” she said, but in one way it isn’t: In taking the job, she realized she would be giving up any chance of seeing Iran again anytime soon. “Because the organization is part of the U.S. government and Iranian officials don’t like that,” she explains. “Maybe I could go back, I’m not sure, but the fear is there, always. They can put you in trouble for anything there. Anything.”

What makes it worth it, Ms. Valinejad said, is the idea of sending music into such a place. One thing she remembers from living in Iran is that love songs weren’t allowed, unless they were songs about love of God or Islam. So into Iran goes a Celine Dion ballad and eight or so other songs every hour on a route from Northern Virginia to Munich, then to a transmitting facility in Dubai, and then into a country where the Iranian government tries to jam the signal and there’s no way to tell who’s listening at any given moment.

One survey – done by calling Iranian phone numbers and asking whoever answered if he listens to Radio Farda – put the number of adult listeners a week at 13.6% of the adult population. It is only an estimate, though, because how many Iranians will speak honestly with a stranger who telephones them out of the blue?

Ms. Valinejad is sure they are out there in droves, waiting to hear what song America is sending next, because if she were in Iran, that’s what she would be doing. “It gives you energy,” she said of the music. “It gives you hope. It gives you something to look forward to.”