Threats to cut down or even cut off federal money for public broadcasting are nothing new. But as raised this past week by Newt Ging-rich, they are casting a chill across the landscape of noncommercial radio and television, for they are generally assumed to be more than mere rhetoric.

Gingrich, who is well on his way to becoming the most powerful speaker of the House in this century, said he planned to "zero out" financing for the Corporation for Public Broadcasting. CPB, which Congress created in 1967, provides $285 million in public money a year, or about 17 percent of the financing for public broadcasting stations.We hear increasingly from the new Republican majority in Congress that we will never be able to get a handle on the budget unless we eliminate the least essential or nonessential items. That's the same line of argument that leads officials to kill off music and art programs in the public schools as frills at budget crunch time.

- GINGRICH ALSO resurrects the old complaint that public television is politically slanted and argues that the public ought not to be subsidizing biased TV involuntarily, through taxes.

Complaints that public television airs "indecent" material also are heard from time to time. (The National Endowment for the Arts, which channels federal money into the arts, has been similarly embattled, especially on the issue of "decency," and now is mounting a counteroffensive although forbidden by law from lobbying.)

Two of the Utahns who are abundantly familiar with, and have dealt with, the complaints for years and are committed to public broadcasting are Bruce Christensen and Fred Esplin.

Christensen is dean of the BYU College of Fine Arts and Communications, was for 10 years president of the Public Broadcasting System in Washington, D.C., and before that was general manager of KBYU and later of KUED. Esplin has been KUED station manager for the past dozen years.

I asked both to address the Gingrich concerns, whether the service can justify the need, the matter of bias, and other questions that have been tossed into the hopper as the new debate over the future of public broadcasting gets under way.

Esplin says that the judgment of "leftist bias" depends on where one is sitting. A number of studies nationally and three locally in the past nine years have asked viewers whether they saw public TV as fair and balanced or as loaded.

- UNEQUIVOCALLY, THEY "regard us as fair, balanced and reasonable," Esplin says. Most of the complaints deal with a few shows, like the remorselessly avant-garde "Point of View" series. "Some of our shows are left-leaning, no question about it. But the conservative critics berate us for carrying Bill Moyers while ignoring that Bill Buckley also is on the air."

Esplin regards "the attempts by some to stifle a free exchange of ideas" as the worst form of censorship.

Christensen says that part of the perception that public TV has a liberal bias stems from the fact that journalists focus most tightly on what is not functioning well and question the status quo. But he says that there is no more fair or accurate TV news program anywhere than the nightly MacNeil-Lehrer Newshour. "So if you are looking for balance, public TV provides it."

The elimination of federal funding would be a devastating blow, Esplin says, with $2.8 million a year coming into the state for KUED, KBYU and the six public radio stations.

- THE MONEY goes directly into programs as "community service grants," in the case of KUED into such fare as "Civic Dialogue" and the statehood documentary the station is completing, and election services. The state public learning channel also would be affected.

Christensen says the first question in the debate over the future of public TV is whether our society wants to have all its media driven by market forces. "I think that is the issue that most often gets blurred. Public use of the airwaves is very much like use of the national parks - a public resource is set aside for public uses that would not otherwise be met by the marketplace."

Critics have suggested that public TV is no longer needed because cable television provides the same services. Christensen responds that the cable argument ignores that people have to pay for it. Furthermore, what kind of cable fare is available depends a lot on where you live. "And cable doesn't take up the slack except in the most popular program genres, like mystery dramas, and then these are interrupted any number of times with commercials, whereas in public TV they are aired commercial-free."

Esplin says that people who carp that public television reaches an elite audience just haven't done their homework. "Nationally and locally the audience is a mirror image of the public. It is true that the most visible programs are those that appeal to an upscale audience, but some like `Sesame Street' draw larger audiences from low-income groups.

"Compared to the networks, our audience is small. But in comparison with cable, we are enormous," Esplin says. KUED reaches 600,000 people a week.

- "THERE ARE FINE PROGRAMS on cable, but you don't find `The Civil War' there, or `MacNeil-Lehrer' or `Sesame Street.' The reason is that they have a profit motive. That's not necessarily bad, but some things just don't play well in the market that are of value, and public TV does and will continue to do them. We need public TV for the same reason we need public schools or public libraries or public museums."

Esplin and his staff met with Sen. Robert Bennett, R-Utah, and aides to the other members of the congressional delegation last week to describe what the University of Utah public station is doing with its federal money. Bennett was a cosponsor of the CPB reauthorization bill and Sen. Orrin Hatch, R-Utah, also has been a consistent supporter of public broadcasting.

Christensen says he would be surprised if the CPB were axed, but thinks it likely some changes will be made in its scope and mandate. "It would be a shame if the federal government were to back out of what has been an extraordinarily successful partnership with states and corporations," he says.