"Bob Johnson," said Gil Lucas as he looked across the Gold Room of the Rayburn Building at the person he had just named "could be successful selling aluminum siding."

Well, Lucas should know, since the company he represents -- Telecommunications Inc., the third largest cable television company in the country -- was impressed enough to buy a 20-percent interest in Johnson's Black Entertainment Television (BET), which debuts tonight on cables across the country.

Johnson owns the other 80 percent of his baby -- a landmark cable network specializing in black-oriented programming -- which he has successfully marked to cable TV companies.

The guests who came to congratulate the proud father were the likes of Del. Walter Fauntroy, Mayor Marion Barry, Rep. Lionel Van Deerlin (D-Calif.), and the sales representative Johnson had hired, who just happened to be former New York Knicks forward Dave deBusschere, who happened to bring along his friend, former Knicks player Sen. Bill Bradley (D-N.J.).

And the executives from Sears, Roebuck and Co. (which signed on as an advertiser on BET), smiled, locked arms, and posed for pictures. They were across the room from the executive from Anheuser-Busch (the first company to become an advertiser).

"Looks like you've got a winner here," said Van Deerlin to Johnson. Then, the congressman added, "All I know is that 10 percent of the TV viewers in Knoxville are black and 90 percent of them have cable."

Johnson chuckled. "I should have you talk to the advertisers."

Later, Fauntroy said to the crowd, "Tomorrow morning I'm gonna eat some Kellogg's Corn Flakes; I'm gonna join the Pepsi generation, and I'm gonna read Time." All three are advertisers on the network.

Johnson, all of 33 and the consumate businessman, has just begun. "I want to read something from someone which describes how I feel about starting out with BET," he said to the group, and quoted, "'My friends in Hollywood would laugh and chortle over our early efforts. They told us we didn't know how to light, we didn't know how to apply makeup properly, the writing was wrong. I would always reply . . . we've got to teach ourselves . . . in time we'll be okay. And in time we did just that.' That statement was made by William S. Paley, chairman of CBS, in his memoirs."

The party guests laughed and then some applauded.

"I'm not saying we're going to be like CBS," said Johnson, who has read Paley's memoirs carefully. "We're going to be better."

For Johnson, this is network pioneering, and it might as well be CBS back in 1949 when they told Paley the writing was all wrong.

"I want to provide a showcase for black enterprise that would be attractive to blacks and whites," said Johnson. "There's no reason why Grambling College football can't be seen all over the country as well as programs showing blacks as lawyers and doctors."

Gil Lucas smiled when asked about any difficulty selling BET to the viewers. "A movie's a movie," he said.

The first week's offering -- the movie "Visit to the Chief's Son" -- was on display on one television set in the room. Another television set played the BET promo. Guests, wearing buttons proclaiming "Bet on IT!" wandered by, gazing at the sets.

"You see that," said Rob Gettinger, pointing out the promo to friends. "I want to tell you how much work went into that. We spent five days . . ." (His agency put it together.)

Of course, Johnson was not content just to rake in the compliments and congratulations. He was still working.

"I'm glad we could play a small role in all this," said Fritz Attaway, vice president of the Motion Picture Association, shaking Johnson's hand.

"You still can," said Johnson energetically. "I need more film products . . ."