THE NATIONAL BROADCASTING Co. is planning, in a few weeks, to invade our living rooms with a Southern epic of the Civil War era called "Beulah Land." The six-hour mini-series has already stirred howls of protest from some writers, actors and activists.

I've just seen a script, and my reaction is: My Gawd, when will it end?

Check out this typical scene from the drama, which is about a white family's life on a plantation over a half century. Four of their slaves -- Ezra, Lovely, Floyd and Paulina -- are given their freedom after the Civil War.

The four, in their "Sunday best," according to the script, stand before the master's "massive desk in his somber, booklined office."

They unanimously decide to stay on in Beulah Land. "Freedom? Do that means we gots to leave Beulah Land?" asks Ezra. Then, lovey pleads in heart-rending fashion:

"I already was my own! I been my own all my life! How come she try to make me less than I am by given' me back to myself? I'm never gonna forgive her."

Later, according to a script, Floyd does leave the plantation -- but only because he has fallen in love with Miss Sarah. Then, after seeing the world, he returns to good old Beulah Land.

Changes wer made in one script to improve the character of Floyd and make him less motivated by his attraction to Sarah. Certain watermelon scenes also were eliminated.

How was such a script ever approved in the first place?

When are the celluloid moguls going to stop producing blacks only in negative stereotypes that are designed to make black people feel powerless and white people feel powerful? It is as if negative reinforcement in the technological age's medium for keeping blacks in their place.

Veteran television producer David Berger has lebeled protests against the show as "an ad hoc thing by a few malcontents."

"We're not doing 'Roots' or "Mandingo,'" he said last week. "I'm doing a romantic novel with a lot of commercial appeal."

But I have yet another concern about the role of television programming like this . I think it is a wedge that drives deeper a generation gap between some black parents and their children.

It's like this: A the hard-won gains of the 1960s have been -nternalized into the mainstream, some under-25 blacks can't appreciate the price their parents paid to get the limited benefits they have achieved. They see progress, but they can't understand the pains or the cautions of their parents.

Transmitting black heritage, it seems to me, is the key to closing this gap. Families can do this through stories, biographies and discussions of their history. But by continuing to distort black heritage, television tears down the self-esteem of blacks of all ages.

White Americans rarely know about the culture and heritage of this country's other groups, although minorities are forced to know a great deal about the dominant culture in order to live, work and get an education.

Television is the powerful medium that partly fills this void, and mainly it fills it disastrously.Television is passive, status-quo pap for all its viewers, but it needs to apply higher standards to black shows than it applies to white show in order to reverse the years of damage already done.

But what do the great purveyors of the wasteland do? They bring us "Beulah Land," which a coalition of blacks found "demeaning. . . . degrading . . . and dangerous."

"Roots" and "Roots "II" showed us that good drama could also be good box office. That should have signaled the networks that there is an endless audience of black drama, but not suprisingly, it did not.

Meanwhile, shouting in anger against television's stereotyping has become almost an historical role. It's one I, for one, am weary of. I'd rather control the images.