'Black dollars' campaign will point up black buying power in 28 cities

''Let your dollars march for you,'' declared Benjamin L. Hooks as Black Dollar Days began Sept. 1 throughout the nation. The ''black dollar'' represents black people's buying power in the form of $2 bills and Susan B. Anthony $1 coins. The National Association for the Advancement of Colored People (NAACP) launched the five-day campaign Sept. 1 to encourage American enterprise to help black Americans through hiring them, promoting them, and negotiating contracts with minority enterprises.

''Money can do more for us than pay our bills,'' says Mr. Hooks, the NAACP's executive director. ''Our black dollars can be our tool for better jobs, for getting business to utilize black professionals, black service firms, and black producers. They tell business we will spend our money with people who give us a fair share of their expenditures.''

Throughout the nation, NAACP branches in 28 cities are taking varied approaches:

* Black Bostonians will offer $2 bills or Susan B. Anthony $1 coins every time they use public transportation over the Labor Day weekend. And they will also shop downtown with the same bills and coins.

* Throughout New Jersey, black businesses have pledged to pay their employees with $2 bills and Susan B. Anthony dollars.

* Churches will encourage congregations to contribute only $2 bills and Anthony dollars in collection plates.

Minority-owned banks and other cooperating banks have extra $2 bills and Anthony coins to exchange for other currency, says L. R. Byrd, the man who conceived the black-dollar-day idea.

''Public transportation and downtown businesses show black people no respect when it comes to hiring and promoting them or dealing with minority firms,'' said Henry Owens Jr., president of the Boston branch of the NAACP.

''Black people are more than 30 percent of the riders of public transportation. Too many mainstream firms take our business for granted.''

Michael Lawrence, NAACP economic development specialist, summed up the ''black dollars'' mission:

''We seek to change the nation's perception of us blacks through the understanding that we will no longer spend our money where we can't work or do business.''