"Knots Landing," which returns as a two-part, four-hour miniseries tonight and Friday, went off the air in 1993.

But the show wasn't so much canceled as it was put out of business.The ratings were still pretty good, but it was increasingly expensive to produce. And CBS paid a higher license fee (what a network pays the production company for the show) for "Knots" than for anything else it had on the air at the time.

"We didn't have to end it when we ended it," said creator/exec-utive producer David Jacobs. "What was happening, though, was a process of attrition. . . . We were amputating characters every year because the show was getting more and more expensive."

Increased costs are common for any sort of TV show. As the years pass, the actors get annual pay hikes - as do members of the production staff - and the costs spiral upwards. Despite the increased costs to the production company, Jacobs said the show was actually operating with a reduced license fee from CBS in its later years.

So "Knots," which had prospered opposite shows like "Hill Street Blues" and "L.A. Law," fell victim to the accountants.

To combat costs, some characters were written out. Others - even those who had been with the show since the beginning of its 14-year run - appeared in a reduced number of episodes.

"I think we all felt that rather than continue to amputate limbs, which is really what we were doing, that it was just time to stop," Jacobs said.

The death of Laura (Constance McCashin) was driven by the need to cut costs, not by the storyline.

"We couldn't afford to keep Julie Harris," co-star William Devane said in amazement. (The award-winning actress played Lilimae Clements from 1981-87.)

Jacobs said he agonized over losing characters "through attrition . . . to save money."

"It wasn't fun to do that. And it was harder to keep the show's texture," he said.

And his partner, executive producer Michael Filerman, agreed.

"Though it boils down to the bottom line - economics - you really are losing members of your family," Filerman said. "So that really took a lot of the joy out of it."

So how could the producers afford to make "Back to the Cul-de-Sac?" The actors worked for less than their usual fees because of their affection for the show.

"If they'd said, `You can stay on for another 10 years,' I would have stayed on for another 10 years - in a heartbeat," said Ted Shackelford (who played Gary Ewing), one of two actors who was with the show throughout its 14-year run.

As for the other actor who made it from beginning to end, Michelle Lee (Karen Fairgate MacKenzie) said she would have remained indefinitely as well. "I was just hitting my stride," she joked.

VIDBITS: Although everyone is expecting "Seinfeld" to return next season, it's not a done deal yet. The Los Angeles Times is reporting that while Jerry Seinfeld has agreed to a new contract - he'll reportedly make $1 million an episode - co-stars Jason Alexander, Julia Louis-Dreyfus and Michael Richards have not yet come to terms.

They reportedly want a two-year commitment and a big raise. (They're currently struggling to make ends meet on only $150,000 per episode.)

- Mary Hart is celebrating her 15th anniversary as co-host of "Entertainment Tonight."

Imagine - a decade and a half of smarmy gushing.

- Cable's USA Network is certainly a study in contrasts. The home of low-budget original programming and sleazy movies, the channel just donated another $1 million to PBS's "Charlie Rose."

USA is the only cable or broadcast network to underwrite a PBS program.

- NBC anchorman Tom Brokaw is splitting the cost with his network to fund a pair of $10,000-a-year college scholarships.

Most of us need not apply, however. The grants will go to children of full-time NBC employees.

- Candice Bergen will make an appearance as Murphy Brown in an upcoming episode of "Ink." The episode reveals that Murphy has had a decade-long "same time, next year" relationship with Mike Logan (Ted Danson).

"Ink" is executive produced by Diane English, the creator and longtime executive producer of "Murphy Brown."