NBC Regains Its Luster With Potent Shows : Television: The revved-up network is challenging No. 1 ABC with adult fare that also appeals to younger viewers.

Guess who’s back.

NBC.

The titan of 1980s television, following a ratings nose-dive after the decline of the Bill Cosby era, is suddenly setting off fireworks in the 1990s.

No, it’s not the No. 1 network. ABC is still on top, and Fox continues to progress. But what NBC has is the buzz. It’s the talk of the industry and the hot network on Madison Avenue as it challenges ABC for the prime-time lead.

In the last two seasons, NBC has introduced a pair of powerful hits that have helped turn the network around. First came the comedy “Frasier” and then, last fall, “ER,” a drama about a hospital emergency room that took off like a rocket and has been the top-rated show five of the last six weeks.

Not since “Charlie’s Angels” in 1977 has a freshman drama managed the same five-week coup, according to NBC.

A bold stroke, typical of NBC’s new aggressiveness, also came up roses when the network bet that ABC’s “Roseanne” was ready to be taken.

NBC challenged “Roseanne” head-on with “Frasier” on Tuesdays. ABC blinked, moved “Roseanne” to another night, switched its franchise show, “Home Improvement,” to checkmate “Frasier,” and thus was forced to shake up two of its successful program blocks.

“Looking back,” says Joel Segal of the McCann-Erickson ad agency in New York, “the move of ‘Frasier’ to Tuesday was brilliant. It forced ‘Home Improvement’ to move. ABC realized ‘Roseanne’ would have died opposite ‘Frasier.’ ”

That we’ll never know for sure, because the switch gave “Roseanne,” at least temporarily, a chance to continue as a winner against lesser competition on Wednesdays. However, after a lengthy run at 9 p.m., the series reportedly may be moved again, to 8 p.m.

As for NBC, its two big nights--Thursdays, with “Seinfeld,” “ER” and “Mad About You,” and Tuesdays, with “Frasier,” “Wings” and “The John Larroquette Show”--are not only carrying the network but defining it.

“It’s quite obviously a network on the rebound,” says Audrey Steele, research executive of the Saatchi & Saatchi ad agency in New York. “It’s a strong growth story and a strong demographic story.”

Although trailing ABC for the season by six-tenths of a point in total households, NBC has made tremendous strides in the 18-to-49-year-old category favored by advertisers.

And in the current, pivotal February ratings sweeps--which helps set ad rates--NBC actually now leads all networks in both total homes and the 18-to-49 demographic.

“They went back to what worked in the past--adult, sophisticated comedy,” says Steele. “I remember when they used to describe themselves to Madison Avenue with the phrase ‘mass with class.’

“ ‘Mad About You’ was a great show from the beginning, but sometimes in television it takes time. Look at what ‘Frasier’ is doing against what was the No. 1 show on TV, ‘Home Improvement.’ ”

While “Home Improvement” is still a powerhouse, “Frasier” has been more than holding its own against it. And a guest shot by former “Cheers” star Ted Danson this week helped “Frasier” come within one-tenth of a point of “Home Improvement” in the ratings.

ABC’s audience, notes Steele, is different from NBC’s--with its comedies generally emphasizing young families with children. NBC, she adds, goes more for adult viewers.

This NBC approach, often with a touch of quality carried over from the “Cheers” era, “is a great signal for broadcasters,” says NBC Entertainment President Warren Littlefield. “It shows quality entertainment doesn’t have to mean low ratings.”

During the final season of “Cheers,” says Littlefield, NBC learned a lesson. Besides original episodes of “Cheers” at 9 p.m., it also ran reruns of the series at 8 p.m., and they did pretty well. Says Littlefield:

“Out of that, we found we can offer smart, funny, adult entertainment at 8 p.m., and that’s what led us to putting on ‘Mad About You’ at 8.”

NBC still has a far piece to go to match the day-in, day-out muscle with which it dominated network TV for six consecutive seasons starting in the ‘80s. On Sundays, for instance, two futuristic dramas, “Earth 2” and “seaQuest DSV,” are struggling in total household ratings but, according to NBC, are doing well with the 18-to-49 audience.

Nonetheless, says Segal, NBC is perceived on Madison Avenue as “comers, guys willing to take chances--and they are producing some of the best dramas on the air.”

NBC’s hope that it is being noticed gets a boost when the New York Museum of Television & Radio’s 12th annual Los Angeles festival opens Wednesday at the Directors Guild Theater. Five of the 18 sessions during the 2 1/2-week festival are devoted to NBC series from this season’s schedule--”Frasier,” “ER,” “Sisters,” “Law & Order” and “Homicide: Life on the Street.”

Four of those series are dramas. And NBC got an added lift in its sweeps performance in recent days when, in addition to the Danson appearance on “Frasier,” another drama--the six-hour miniseries “A Woman of Independent Means,” starring Sally Field--pulled a respectable audience in its three nights, averaging a 16.6 rating and 25% of viewers.

For McCann-Erickson’s Segal, however, “The big story of the season is that ABC’s ratings with young adults has gone down and NBC’s has gone up.”

On the program front, he thinks that Sam Waterston’s addition to the cast of “Law & Order” is a major reason that the show’s ratings have picked up.

Success on a network is catching, because you have bigger audiences with which to promote other programs.

The solid ratings of NBC’s morning “Today” show in recent months may well be partly attributable to the carry-over viewing of the network from the night before. And Jay Leno’s NBC “Tonight” series, with stronger lead-ins, is a bit more of a threat to CBS’ late-night king, David Letterman.

CBS, in deep trouble with sponsors because of its older image, has fallen from No. 1 to third in households and is dead last, trailing even upstart Fox, with viewers 18-to-49.

Howard Stringer, president of the CBS Broadcast Group, and Jeff Sagansky, president of CBS Entertainment, have both left the network after leading it to three years as No. 1.

It is an irony, because CBS’ success helped revive and stabilize network television. But TV is a cyclical business. At the moment, ABC is rich, fat and comfortable and not nearly as interesting as when it exploded enormous miniseries and other specials onto the TV scene. Fox, meanwhile, is delivering with such shows as “Melrose Place.”

But this season, NBC is where the action is.