Reuven Frank never wanted or accepted the car and driver NBC offered him the last time he was president of NBC News. "I always thought it would ruin my breakfast," he grumps. "I'd be worried about that guy standing out there in my driveway with the motor running."

But now Reuven Frank is president of NBC News again, and, again, abruptly. The last time, from 1968 to 1973, it was because the fondly remembered William McAndrew died, and Frank was entreated to replace him. This time, the respected yet unpopular William J. Small has resigned, and Frank, now 61, has taken the presidency again--and, this time, the car and the driver, too. They show up each morning at Frank's home in Tenafly, N.J.

On Wednesday night, Frank was in Washington to have dinner at the Four Seasons Hotel with, as he said half-jokingly, "my stars," Tom Brokaw and Roger Mudd, who are to take over anchorship of the "NBC Nightly News" early in April. Among the glories of Frank's 30-year career at NBC is the fact that he brought together Chet Huntley and David Brinkley for the "Huntley-Brinkley Report" (NBC would like nothing better than to repeat that feat with Mudd and Brokaw) and later produced "Weekend," still probably the best, and without question the most amusingly cranky, of all TV magazine shows.

"Huntley-Brinkley" used to close with the second movement of Beethoven's Ninth Symphony. "Weekend" would open with host Lloyd See FRANK, B6, Col. 1 FRANK, From B1 Dobyns telling viewers just how many commercials and station breaks they would have to sit through during the ensuing 90 minutes, and it included such observations on the passing scene as, "Cloning is the genetic equivalent of television programming." Frank himself wrote most of the "Verbals" on the show--little sayings on the title cards that separated the program from the ads--and one of them was "Only Solemnity Is Frivolous."

In recent years Frank cooled his heels on the periphery of the fray. He produced two outstanding documentaries on American productivity, "If Japan Can, Why Can't We?" and "America Works When America Works," both of which made seemingly stiff and untelevisable subjects manageable and fascinating. But he was bored. He didn't want to write a book about television because, he repeatedly said, if he did, "it would be the first book on television I ever finished reading." But on Feb. 1, when NBC president Robert Mulholland approached Frank about replacing the cantankerous Small, he was intrigued. Besides, he says, his wife of 36 years, Beatrice, told him it was driving her crazy having him around the house.

TV journalism is not overpopulated with either gentlemen or scholars. Frank would duck the scholar moniker and give it a harumph, but in fact, both labels fit him. There are those who have worked with him who would tolerate no less an estimate of Frank than that he is brilliant--a wry, dry, wiry, witty, classy, crabby old genius.

"Happy? No, I'm not happy," said "Weekend's" Dobyns when asked for his reaction to Frank's reascendancy. "I'm totally ecstatic."

That doesn't quite describe Frank's own response. "The job is kind of frightening," he concedes. "Somehow or other I've got to coax almost 1,000 people to pull in the same direction." But producing those two documentaries have made him an expert on productivity, right? "No, I'm an expert on what doesn't work. I'm a real journalist; all I know is what's wrong. I don't know how to fix it.

"I have no first priority," he says bluntly. "I have no plan." He assumes the presidency when network news is more competitive than ever, and as NBC is about to launch its new nightly initiative against top-rated Dan Rather on CBS and the troublesome, bubblesome Roone Arledge production on ABC. Some would say NBC News is not ready for the fight, that morale is low, internal friction high, ratings of programs like "Today" not so hot. Frank says, "It isn't that bad. It's not a disaster. Not an embarrassment. Not an emergency in terms of what's going on the air."

Frank would have to be lumped with the loftiest figures in broadcast journalism, but he doesn't like lumping and he bristles at loftiness. He says, however, that he does feel up to a fight, and he does want to cream the competition. "I'm used to creaming the other guys," he says. "I've done it before. Creaming people is good for the blood. It's the soul of journalism. It means beating them and doing it better. In the days of 'Huntley-Brinkley,' we rarely watched the competition. We said, 'Let them watch us,' and they did.

"I have watched the other guys in recent weeks. They do a pretty good news show. But I see very little flair anywhere--editorial flair." Last year, asked to size up the three network nightly news shows, Frank said, "They're all the same, and they're all dull."

One of the weakest productions of NBC News is its pathetically low-rated and enervated "NBC Magazine," ironically an offshoot, several generations removed, of Frank's "Weekend," which Fred Silverman first praised, then destroyed. Frank says he is not ready to dump the magazine show yet. "I want to think if we should do a magazine show. Not 'Weekend,' because there's no sense looking back. Although I'd be happier doing that producing 'Weekend' again than anything--but so what?"

Television news now is a different jungle than when Frank last ran NBC News. He's aware of that, perhaps painfully. "The most affecting phone call I got was from Irene McAndrew, Bill's widow. She just thought it was marvelous, she said that it would be as of old. It really can't be as of old, but it was awfully good to hear her voice." The equipment has changed, among other things; "you go into an e-j electronic journalism room now, and it's like being in a video games arcade," Frank says. "It's just like Pac-Man."

ABC News and Sports president Roone Arledge is widely credited with, or blamed for, popularizing glitz and blitz. Frank says, "I think Roone Arledge has been in some ways a healthy influence," and "I think he demonstrated ways of using the equipment. On the one hand, you should not shut your mind to new tools. On the other, tools are not purposes."

During the past few years, Frank was occasionally available for chats about the sometimes wacky world of broadcast journalism and about the just plain wacky world. During one session, he grumbled, "I think that generally, television news as an institution has become so mannered that its very wide acceptability has eroded." He abhors "the rise of the reporter as institution," a trend he thinks reached its deplorable worst ("I was outraged") when Dan Rather sassed back President Nixon during a Dallas press conference.

The trouble with the network news staffs now, Frank said, is that "they don't go out and seek. There are reasons for this and they're easy to understand, and part of it is they're undertaking the burden of being the prime source of information. I'm not sure they're entitled to it. But the Roper Polls say you're it and you walk around like you're it and it's a little like holy orders.

"And in my time, you didn't go into news for that. It was not holy orders. We thought it might be fun. . . . Now, it's so deadly. And when it is leavened, it is so self-conscious and so obvious--'Hey, folks, we got a funny one.' A lot of things are interesting that are not important. A lot of things are important that are not solemn. And it's not that they cry the end of the world all the time; it is, somehow, 'I am Sir Oracle, and when I speak, let no dog bark.' And I don't like it. I'm as smart as those guys."

Now he is one of Those Guys again. "My biggest problem," Frank says, "is that I am, in fact, much more ignorant of the procedures and institutional structure than people expect." For now, Frank is making no grandiose predictions; he says there will be "a lot of waiting" for his moves. "It's a revolutionary change in my life," Reuven Frank says, "not a revolutionary change for NBC News."