It was a major televised moment in Washington's history, and it was played out on one of the city's smallest television stations.

When Marion Barry announced on June 13 that he would not seek a fourth term as Washington's mayor, he chose WHMM's "Evening Exchange," hosted by Kojo Nnamdi on the campus of Howard University, as the setting for his announcement.

"I was frankly surprised," said Nnamdi. "It was his decision. I played no part in it all," he said of Barry's decision to make District history on the hour-long public affairs program airing weekdays on Howard's public television station.

The mayor's announcement gave "Evening Exchange" its highest rating ever and focused attention as never before on the program, Channel 32, and Nnamdi, the station's most identifiable personality.

In his announcement and subsequent interview, Barry said he had chosen "Evening Exchange" because, as the product of a segregated upbringing, he wished to make this announcement at an important black institution and away from the "rude and disrespectful" among the Washington media.

During Barry's appearance, "Evening Exchange" reached a peak Nielsen rating of 4.13. Each ratings point represents 17,000 households. Its peak share was 8.8 percent of the sets in use.

Barry has been on the show about four times in the last 16 months. WHMM capitalized on his latest, exclusive appearance by keeping an identification line on the screen throughout the broadcast. Taped excerpts played on other stations gave WHMM even more exposure.

By choosing Channel 32, Barry may have been seeking a shelter from the media storm. In Nnamdi he encountered an interrogator who was both congenial and pointed. He quizzed the mayor on the timing of his announcement and its relationship to his legal problems; he also pointed out that as president of the school board, city council member and as mayor, Barry had done a lot for Washington.

Nnamdi's interview of Barry, following the mayor's taped announcement, has put him in demand, with a number of news organizations seeking interviews. But he remains the straightforward, even-keeled presence who has guided "Evening Exchange" for five years.

"I don't plan on doing any {TV or radio interviews}," he said. "I don't like the idea of becoming the news ... I'm nowhere near the center of the story ... I don't see myself as a political pundit, and don't like to be cast as one."

The show that Marion Barry chose for his announcement resembles other local news analysis programs in some ways, but is distinctly different in many others. While the program tackles many of the staples of Washington news shows, it does so from a different perspective, presenting views, guests and experts seldom heard on other shows. The chairman of the District wing of the Communist Party of the United States, for instance, has been a guest.

"You will not see on any other talk show anybody who says 'I am Marxist, I am a Communist, and this is my view of the invasion of Panama.' It absolutely shocks me at how casually spokespersons for the extreme right get on television to participate in a discussion and you never see spokespersons for the extreme left, and when I say extreme left, I mean extreme -- Communists, I am talking about," said Nnamdi.

At the same time, representatives of groups such as the Heritage Foundation and the Brookings Institute are also heard from regularly on "Evening Exchange."

In addition, the program presents discussions on issues of black history and culture that rarely figure on other shows, from black nationalism to black hair and the relevance of Black History Month.

Kojo Nnamdi, 45, took over as host of "Evening Exchange" in April 1985, and the show is a reflection of the man. He brings a background as a hard-news reporter at WHUR for several years between 1973 to 1985, an international orientation -- he was born and brought up in Guyana, a British colony until the year he left -- and an earlier involvement in the black power movement.

Nnamdi was 21 when he left Guyana in 1966 to study at McGill University in Montreal. He carried with him the lessons of racism he learned under British rule.

"We were people of color, and they {the British} were white," he said. "So we understood very clearly that there was a relationship there that was based on color."

Nnamdi left Canada for the United States in 1968. He spent a year in New York, where he was involved in the theater and was married for the first time.

Nnamdi came to Washington in 1969, after the city's whirlwind of civil disorder, at a time when black activism was in full sway. He studied at the Center for Black Education and eventually took an African name.

The now-defunct center was the focus of his own activism. The splits within the black power movement in America and his own international orientation led Nnamdi to embrace the center's Pan-Africanist philosophy, he said, the idea that black power rested in the worldwide unity of people of African descent.

The center operated an educational program devoted to "teaching all disciplines within a black historical context," he recalled. Nnamdi was enrolled in a program that today would be described as "Afro-centric."

Affiliated with the center were the Drum and Spear bookstore, which he managed in 1971 and 1972, and the Drum and Spear Press, which published books on Pan-Africanism and related topics. The Center was also active in the community, operating a pre-school, renovating homes and running a health center.

During his early years in Washington, Nnamdi also studied community education at Federal City College, which has since merged with the University of the District of Columbia. When he last checked, he was six credits short of a B.A.

He was also involved in local radio, acting in and directing children's plays for a Sunday children's hour on WOL radio in 1969 and doing news commentaries for the station in the early '70s.

Nnamdi, who was born Rex Paul and remains so legally, changed his name in 1971 to strengthen his sense of African identity. He chose Nnamdi (pronounced nahm-dee) because of his admiration for the independence leader and first president of Nigeria, Nnamdi Azikiwe. Kojo means "born on a Monday." He has been an American citizen since 1983.

In 1973, Nnamdi abandoned his political involvement to go into journalism.

He joined the news department of Howard University's FM radio station, WHUR, and trained on the job there, working first as an editor and then as a reporter covering Capitol Hill, local politics and labor relations.

Between 1980 and 1984, he was director of news and information at WHUR, but a labor dispute resulted in his assignment to host "Insight," a 20-minute nightly news analysis segment, where he caught the eye of WHMM producers.

In 1985 Nnamdi succeeded Bernie McCain as host of "Evening Exchange."

"I'm a very lucky person," said Nnamdi. "I don't know very many other black people in America who are able to have a one-hour-long daily talk show during which they are allowed to interpret events and, from time to time, offer opinions on subjects," he said, adding, "Oprah Winfrey, obviously."

Nnamdi said that no one person had inspired him to do what he is doing today, but that "a complex web of social circumstances" had made it possible. From his father, who worked as a government clerk in Guyana, he learned the work ethic; from the life of Paul Robeson, a thirst for knowledge.

"But I have also picked up a great deal of what I understand about life from people who would not under any circumstances be considered role models ... people who have been drug addicts for 18 years, but who have a remarkable amount of insight and information as a result."

Nnamdi lives in the District's Shaw neighborhood with his 18-year-old twin sons, Ketema and Kehinde, both students at Howard. His mother completes the household.

Another son, Pierre, by his first marriage which ended in divorce, is 21 and serves in the U.S. Army in Germany. Nnamdi's second wife died in 1982.

He also has a brother and a sister in the United States, and a brother remains in Guyana.

Nnamdi's stay in the United States has lasted longer than he had planned. He went to McGill University "fully intending to return home immediately after completing my degree." But his involvement with the black consciousness movement held him here.

Still, he plans to adjourn to the Caribbean for its slower pace, to reflect on and write about events that have occurred here. He would also like to live in Europe and Africa.

Nnamdi's sensitivity to the African-American experience of exclusion from the social mainstream is reflected in his commitment to doing what he calls "all-inclusive" television.

"We feel that the most cruel thing that was done to us as a people was being locked out ... The lesson we learn {from that} is that you no longer prohibit or inhibit access to the public airwaves once ... people are rational, informed and articulate. We cannot operate on the basis only of how large a constituency they represent because if that was the basis on which we operated, Jesus may never have walked the earth, you know. He only had 12 disciples and he certainly wasn't a politician."

"Evening Exchange" is WHMM's top-rated program, drawing a largely black middle-class audience by station estimates, and it is one of the city's few call-in television shows. As the show's tenured host who also functions as its managing editor, Nnamdi is Channel 32's most visible personality.

Each week, Nnamdi devotes four evenings to in-depth discussion with experts on local, national and international issues, and a fifth (Fridays) to news analysis.

The Friday program brings together a wide range of journalists, including Tony Snow, editorial page editor of the Washington Times; freelancer Brenda Wilson, formerly of National Public Radio; Barbara Reynolds of USA Today; Juan Williams of The Washington Post; Joe Davidson of the Wall Street Journal, and Bonnie Erbe of NBC radio.

WHMM will offer a half-hour edited version of the Friday night news analysis show, "Reporters Roundtable," to PBS affiliates this fall.

Nnamdi and his producers often examine issues from the other side of the color line. For instance, when American forces invaded Panama, most coverage centered on the number of American servicemen killed and injured.

"Our first question was, how many Panamanians are being killed, because we understand that most of the people in Panama look like us, and so our immediate concern was for their lives," he said.

"We serve to prick the consciences of people about how they view people of color around the world."

In addition to its core audience of black viewers, Nnamdi said the show also has a "very loyal," if smaller, white viewership. With the show's orientation toward people of color, Nnamdi worries that "subconscious prejudice" leads most white viewers to tune it out.

"They see absolutely nothing wrong with our kids watching commercial television for seven or eight hours a day, or white television, but it never occurs to them that their children should watch Channel 32 for two or three hours a day," Nnamdi said.

"We continue to be obligated to understand and appreciate European culture, but they are under no similar obligation to understand and appreciate black culture."