Miguel Sandoval arrived in Harlem in 1959 from Havana, where he'd been an outspoken advocate of better civil rights for black Cubans. Sandoval was Cuban, but he though of himself primarily as a black. Yet to the American blacks in Harlem, he was a Hispanic.

Nine years later, he applied for a job as director of the manpower office where he worked because he had heard that federal officials were looking for a black to fill the post. But, Sandoval said, he was told he could not have the job because he was Hispanic.

Sandoval convinced the federal Equal Employment Opportunity Commission that he was indeed black and had been discriminated against, and won back pay. Still, Sandoval, like many black Hispanics here, has found himself walking a delicate tightrope between two worlds -- one black, one Hispanic -- and feeling comfortable in neither.

"The U.S. classifies as black those people of African origin. Hispanics are classified as people of Hispanic origin or from Latin American countries," said Sandoval, who now lives in Washington. "In that category, I am Hispanic, as I am from Cuba. The census would count me as Hispanic -- not black -- even though in fact I am black. It's a dilemma."

It is a particular social dilemma here in Washington, black Hispanics say, where the population is 70 percent black and blacks and Hispanics have frequently viewed one another as competitors for pieces of the political, economic and social services pie.

Daniel Bueno, the owner of the highly successful Zodiac Records store on Columbia Road, remembers when he first came to Washington 18 years ago, and the Hispanic community was much smaller, he moved in a circle of American blacks. Bueno looks back now and chuckles -- the way people chuckle about their adolescent escapades -- when he remembers how he participated in the 1968 riots here and the Poor People's March.

Now, Bueno has cast his lot with his fellow Latins, selling the music of their native countries -- and his -- in the heart of Washington's "barrio latino" on Columbia Road. "I feel better now. (Latinos) understand me and I understand them. When I go with blacks, I have to pretend. With Latinos I can be myself. I do my thing," said Bueno, who could pass for a teen-ager at 33 and spends a lot of his time arranging music for well-known Latin singers and groups.

According to the best current estimates, there are about 75,000 Hispanics living in the Washington area. But none of many surveys done on area Hispanics enumerates the number of black Hispanics. Perhaps that is because it is a curious, confusing question for black Latinos to have to define themselves in an "either/or" context.

"Here in the U.S., the line of demarcation [between races] is very clear. You are either black or white," said Roland Roebuck, a Puerto Rican who works in the D.C. Office of Latino Affairs, "whereas in Latin America, you have a lot of shades of white and black." Roebuck, who is black, was born in New York City but lived most of his life in Puerto Rico and the Virgin Islands.

Those Latinos who are dark-complexioned, but not black, said Roebuck, "suffer a shock when they come here because they are placed in with black folks and treated accordingly. Here, you are forced to put yourself in a race category . . . (Black Hispanics) are forced to define themselves (as black or Hispanic) and often they don't know which way to go."

It is not that racism does not exist in Latin America, said Roebuck and other black Hispanics. There, a person's color is almost always tied to his economic status. Yet it is a person's economic status, rather than their color, which determines the social sphere they may travel in.

The prejudice was more subtle in Cuba, says Sandoval. When he lived there under the Batista government, there were beaches and clubs where blacks could not go. "But a white Cuban might say to a black, 'Oh, you are my brother.I'll sign for you to join the club. sBut it's a $1,000 fee.'

"Now you know and they know the black can't afford the $1,000. So they kept them out that way and it looked like they weren't keeping you out because of color."

Says Dr. Norma Small, a black from Panama and a chemistry professor at Howard University, "When I was home [in Panama], I didn't see racial prejudice so much because I was darker. It was not so much a color thing as how much money you had. We have black people in Panama who are very rich and they can go anywhere."

The major complaint of black Hispanics is that although they belong to both groups, they often lose out on the affirmative action programs of each group.

Small said she knows of black Hispanics who have applied for federal job training programs for Hispanics, and despite their qualifications, we're turned down. "You get the feeling that what they want when they want Latins, are people who are easily identified as Latins," said Small, who's lived here 14 years.

Sandoval has recently written to President Carter, who has declared this week National Hispanic Heritage Week, and congratulated him for appointing more than 100 Hispanics to policy-making positions, but complaining that the president "has forgotten that some blacks are Hispanics, too."

Sandoval, who has worked at Manpower and the Department of Commerce, and is now active in the National Alliance of Spanish Speaking People, says that more than 250 Hispanics are working as employment program coordinators in federal agencies, but only a handful are black.

Washington Hispanics do say, however, that in recent years, there have been some improvements in the dialogue between American blacks and Hispanics. Sandoval points to the two-year-old National Working Consent Committee of Blacks and Hispanics, whose members include several national Latino and black leaders. In addition, a Washington group, the Local Latino, Hispanic and Black Coalition has also been formed.

"We are beginning to understand we have to get together on issues," said Sandoval. "But it takes time. You know, there is no complete unity even within the Hispanic community."