TELEVISION : Why’d NBC Pick Thursdays? : The network has owned the night for a dozen seasons. Can other networks ever hope to get a piece?

Thursday nights on NBC are a lot like automatic teller machines. Both have been created within our lifetime, but it’s nearly impossible to remember a time when they didn’t exist.

There was an era when getting cash meant standing in a long line at the teller window and NBC Thursday nights meant “Lewis & Clark” and “Harper Valley PTA.” Somewhere along the line, though, cash became available on every street corner and watching NBC’s Thursday shows became almost like a job requirement.

If you can’t discuss Matt LeBlanc’s encounter with a randy tailor on “Friends” or Jerry’s encounter with the Soup Nazi on “Seinfeld,” you won’t be able to keep up with the water-cooler conversation at work on Friday. A lot of people may watch ABC’s “Home Improvement,” but it’s the state of Anthony Edwards’ marriage on “ER” that has lunch tables buzzing the next day.

“The evening is like a national town meeting,” says Cheri Steinkellner, a former producer for NBC’s Thursday night staple, “Cheers,” who co-created another former Thursday night show, “Hope & Gloria.” “You don’t want to be the one person the next day who didn’t see that funny gag on Thursday night.”

For a dozen seasons now, NBC has dominated Thursday nights, going back to the fall of 1984, when it introduced a lineup of “The Cosby Show,” “Family Ties,” “Cheers,” “Night Court” and “Hill Street Blues.”

There have been plenty of changes through the years. Some worked well, like “Hill Street” giving way to “L.A. Law,” which in turn was replaced by “ER.” Others did not. (Raise your hand if you remember “Rhythm & Blues” or “Grand.”) Through it all, though, NBC has continued to be the channel of choice on Thursdays.

It’s not unusual for a network to rule a night of programming for an extended period. ABC has owned Tuesday night since the mid-’70s, starting with “Happy Days” and continuing with “Who’s the Boss?,” “Moonlighting,” “Full House” and “Roseanne.” And CBS’ mid-’70s Saturday night lineup of “All in the Family,” “MASH,” “The Mary Tyler Moore Show,” “The Bob Newhart Show” and “The Carol Burnett Show” is considered a high-water mark for quality television.

But never has one night of programming so dominated the nation’s weekly viewing habits.

“One of the key differences between NBC’s Thursday night and other big nights for networks is that three of the consistent top shows in television--’Friends,’ ‘Seinfeld’ and ‘ER’--are all on the same night. That’s pretty unusual,” says Steve Grubbs, senior vice president for national television buying at the advertising agency BBDO.

So far this season, the five NBC Thursday shows, including freshman sitcoms “The Single Guy” and “Caroline in the City,” are among television’s six top-rated shows, with only ABC’s “Home Improvement” (at No. 5) breaking up the clean sweep. About 30 million people watch them each week. Even more significant, while 59.8% of the country’s homes are watching TV on an average night during the rest of the week, that figure grows to 63.1% on Thursday nights.

As NBC Entertainment President Warren Littlefield puts it: “Our Thursday night schedule holds a mirror up to a large number of Americans. Single, married, young, old--pick a category, pick a type, and they’re watching.”

I n 1981, NBC might as well have been airing a three-hour docu mentary on the history of toast for all the ratings heat the network was generating. It had come up with one critical hit that spring, “Hill Street Blues,” which aired at 10 p.m. Thursdays, but the show wasn’t producing big ratings and the network was getting clobbered for the evening by a CBS lineup that included “Magnum, P.I.” and “Knots Landing.”

“We were stumbling around in the dark,” recalls Brandon Tartikoff, who was NBC Entertainment president at the time. “I’d be lying if I said we had this great vision of what to do. We were just going up against a powerhouse in CBS and just wanted to come in second.”

In the fall of 1982, the network came up with a lineup that included “Fame” at 8 p.m., followed at 9 p.m. by a new sitcom called “Cheers.” “Taxi,” which ABC had let go, went on at 9:30, and the evening ended with “Hill Street.” Critics began calling it the best night of programming on TV, but the ratings gains were modest at best.

So much for quality television. When the next season rolled around, the network led off the night with three routine sitcoms in “Gimme a Break,” “Mama’s Family” and “We Got It Made,” followed by “Cheers” at 9:30 and “Hill Street” at 10.

“We wanted to build the schedule backwards, and ‘Cheers’ gained an audience when it came directly before ‘Hill Street,’ ” says Tartikoff, who now is chairman of New World Entertainment.

Says Littlefield, then one of Tartikoff’s programming lieutenants: “Once we had ‘Hill Street’ and ‘Cheers’ in place, a signature started to emerge. It was ‘Smart Thursday.’ We saw the viewers who had left network TV starting to come back to watch these shows.”

Then came 1984, when “The Cosby Show,” which Tartikoff refers to as “the balloon that inflated the whole night,” premiered at 8 p.m. It was followed by the already well-regarded “Family Ties,” moving over from the Wednesday schedule. “Cheers” settled in at 9 p.m., followed by a new show, “Night Court,” and then “Hill Street Blues.”

The network had smacked a home run, critically and commercially. Littlefield witnessed NBC’s success firsthand: “I’d be in a grocery store on a Thursday night and see people racing out to be home by 8. That’s when I knew we had something.”

That something was a financial bonanza. By airing the sort of critically acclaimed programming that lured young urban professionals back to television, NBC roped in more advertising dollars.

“During the zenith of NBC’s Thursday night reign, Part 1, the movie studios were lining up to get into the night while, conversely, our programming kept people from going to the movies on that evening,” Tartikoff says.

Explains BBDO’s Grubbs: “The night has long been the home of NBC’s more sophisticated shows. That attracts a younger, more affluent audience, which advertisers will pay a premium to be associated with.”

B eing good proved to be both a blessing and a curse for the network. It helped build Thursday night and then nearly destroyed it. The first hint of trouble came in 1987. The move from one Steven Bochco-produced show, “Hill Street Blues,” to another, “L.A. Law,” had gone smoothly enough, but “Family Ties” moved to Sunday and was replaced by the “Cosby” spinoff “A Different World,” which wasn’t nearly as well-received by the critics. It got strong ratings but didn’t measure up in terms of sophistication.

In 1990, when “Grand,” created by “Cosby” producers Carsey-Werner Productions, went on at 9:30, it looked like the beginning of the end.

“With the success of the night, we began to see certain parts of our real estate being demanded contractually,” says Tartikoff, who left the network in 1991. In other words, when the network signed “The Cosby Show” to a two-season deal, it agreed to give “Grand” the coveted time slot behind it. A similar situation occurred with “Wings,” produced by Paramount Television, the same company that supplied NBC with “Cheers,” which took over the 9:30 showcase in 1991.

“Grand” was a quickly forgotten flop, and “Wings” struggled for respect and ratings. When “Cosby” itself went to syndication heaven in 1992, Littlefield realized that “we had bobbled the ball.” “Rhythym & Blues” was a dud.

The only show left from the glory days of the mid-1980s was “Cheers,” so NBC began airing reruns of the show at 8 p.m. and new episodes at 9 p.m. Then, in early 1993, Littlefield experienced “the darkest hour of my professional career.” The cast of “Cheers” was calling it quits.

“We were close to losing our night,” he says. “Thank God for ‘Seinfeld.’ ”

That show had been languishing on Wednesday nights, along with “Mad About You.” NBC slipped “Seinfeld” into the post-”Cheers” slot in February and it took off--quickly establishing itself as the logical successor to the 9 p.m. “Cheers” slot come fall. Not coincidentally, the network then gave the “Cheers” spinoff “Frasier” the 9:30 spot for the 1993-94 season, and it also turned into a hit.

The magic wasn’t flawless. “Madman of the People” was introduced at 9:30 last season and, though it was a Top 20 show, wound up getting canceled at mid-season because it neither held onto the “Seinfeld” audience nor won critical favor.

“The Single Guy” and “Caroline in the City,” this season’s new Thursday entries, haven’t won critical plaudits either, but they seem more comfortably hammocked between “Friends,” “Seinfeld” and “ER.”

Littlefield acknowledges that he was apprehensive when the season began.

“I was in New York for the first Thursday of this season and I couldn’t sit still,” he recalls. “I finally left my hotel and started walking the streets, peeking in windows to see what people were watching. Finally, I went into a restaurant and saw all these people there. I panicked, and all I could think was ‘They’re not home watching our shows!’ ”

But plenty of other people were.

“They’ve reseeded the forest,” Tartikoff says. “The way to keep things going is just the way they’ve done it. Gain control of your real estate and come up with shows that appeal to the same mix of sensibilities.”

David Crane still savors the moment he got the news the sitcom he helped create and produce, “Friends,” had landed a Thursday night spot.

“It was like winning the lottery,” he says. “We knew what Thursday night is. It’s the best possible shot you’re going to have with a show.”

That’s the upside of being a part of what NBC calls “Must-See TV.”

“You’re handed the key to the city,” explains Marco Pennette, co-creator of “Caroline in the City.” “People don’t have to search for your show.”

But landing a spot on Thursday is “a double-edged sword,” explains Pennette’s partner, Fred Barron. “Now you know that if it isn’t your best, 18 million people will see you with your pants down.”

Says Steinkellner: “You’re expected to keep pace with ‘Seinfeld’ and ‘Friends,’ so a show has less time to prove itself.”

The success of the evening, then, dictates what goes on. Steinkellner admits that when she and her husband, Bill, came up with the idea for “Hope & Gloria,” which aired at 8:30 p.m. Thursdays last season before moving to Sunday this year, the show had “a far different mood, flavor and message” than it did when they learned it might wind up on Thursday nights.

“The opportunity to be on Thursdays was irresistible, so you do what you have to do to get it on then,” she says. “Thursday shows seem much lighter and faster-paced. You’re juggling many story-lines in one episode. Non sequiturs abound.”

Then there’s that other not-so-secret ingredient.

“The shows have to be smart and feel original in some way, but there also is something sexy about them,” Crane says. “Ultimately, while there were funny things about ‘Madman,’ it wasn’t sexy. And that hurt its chances.”

I t’s become a familiar refrain to Brandon Tartikoff. These days, he’s going into network offices to pitch New World shows, and “the situation I often find myself in is having people say, ‘Look, you helped design Thursday nights for NBC. What can you do for us?’ ”

The other networks have tried counter-programming. CBS tried to go for an older audience by moving “Murder, She Wrote” to Thursday this season. ABC tried to go upscale by pitting Bochco’s “Murder One” against “ER.” So far, nothing has worked.

Tartikoff advises that while it’s unlikely anyone can end NBC’s Thursday night tradition anytime soon, the competition would be wise to counter the network by “coming up with cross-forms of television that viewers can’t find anywhere else, like ‘Real People’ or ‘That’s Incredible’ or ‘In Living Color.’ ”

“The reality is that if you present programming that’s more conventional, you’ll fail dismally,” he adds. “But when I propose outlandish ideas, the people who spend their lives programming and reprogramming on Thursday nights tend to get a little shy.”

The Fox network has taken another approach. By programming shows like “Living Single” and “New York Undercover” on Thursdays, says network entertainment chief John Matoian, “we’ve been incredibly successful in comparison. We have a large, urban, ethnic-skewing audience.”

This approach may never win the night or become a cultural tradition like NBC’s Thursday, but Matoian figures it is “a salvageable alternative--realistically, we feel that if we finish a strong second, we’ve done as well as we can do.”

It must be nice to know the competition is shooting for the silver instead of the gold, but Littlefield insists that NBC never takes the night for granted.

“We know we must bring change. The mistake we made in the ‘80s was letting our shows just sit there, and by the time a show got old, we couldn’t move it,” he says.

So, like a basketball team trading its star players while they still have some value, the network has been shipping its Thursday night shows off to Tuesdays (“Wings,” “Frasier”) and Sundays (“Mad About You,” “Hope & Gloria”). The goal is to make those other nights into what Thursday night has already become while keeping Thursdays fresh.

“Because of the network’s long tradition of success on Thursdays, NBC now sees the evening as its night to build new shows,” says BBDO’s Grubbs.

Because NBC Thursdays are such an institution, being moved from the night could be seen as a demotion. Paul Reiser of “Mad About You” and Kelsey Grammer of “Frasier” were both reportedly miffed when their shows were shipped out.

“Would they move us? God, I hope not! Would we care? Tremendously!” says “Friends” producer Crane.

Still, nothing lasts forever on TV (unless you count PBS pledge drives). NBC may have to worry about a shake-up sooner rather than later if the persistent rumors are true that both executive producer Larry David and Jerry Seinfeld may be ditching “Seinfeld” after this season. Meanwhile, every member of the “Friends” cast seems to be making movies and, Grubbs says, the popularity of “Single Guy” and “Caroline” “may not be as strong if they went to any other night.”

Could the tradition of NBC’s Thursday night be toppled? While Fox’s Matoian thinks there’s a chance “it might waver, as the tent-pole shows like ‘Seinfeld’ soften,” nobody is predicting a return to “Harper Valley PTA.”

Says Littlefield: “Ten years ago, the average household had 10 channels to choose from. Now it’s 40 channels, and the number is getting higher all the time. The notion that you can count on us on Thursday nights is a huge advantage. Some things you just don’t screw around with.”