The National Association of Broadcasters is floating a proposal on Capitol Hill to apply a special tax of 1.5 or 2 percent to sales of television sets, videocassette recorders and radios to help finance public broadcasting.

It is the powerful lobby's response to provisions in a Senate spending package that would raise the money by taxing the sale of radio and television stations, many of which are owned by association members.

"It's certainly a more equitable way to do it than to target one particular industry and say 'You should pay for public television,' " said Edward O. Fritts, president of the NAB. "Clearly consumers should pay the costs of this."

"We're talking about $7.50 to $10 for large-sized sets," Fritts said. "I don't think that's enough to be a deterrent to any family who's purchasing a major television set." In 1988, he said, a 1.5 percent tax would raise $264 million and a 2 percent tax $351 million.

Fritts said the NAB was not necessarily backing the plan, only offering it as something to consider. The association will later this week suggest two other options for raising the money -- auctioning spectrum space to business radio users or putting fees on applicants for cellular radio franchises.

Many countries tax television owners. According to "World Broadcasting Systems: A Comparative Analysis," a book by University of Miami professor Sydney W. Head, about two-thirds of Europe's systems depend primarily on television-set license fees for revenue. About half of African and Asian systems license receivers, but only about 10 percent of the systems in the Western Hemisphere do.

In 1986, French households with color sets for private use paid annual licensing fees of about $103 at current exchange rates. In Britain, the annual rate was about $97.

The NAB noted that a television tax for public broadcasting, which includes both television and radio, was proposed in a report by the Carnegie Commission in 1967. It also notes that from 1950 to 1965, television sets were subject to a special federal excise tax of 10 percent.

The station transfer tax is contained in a budget reconciliation measure reported out on Oct. 21 by the Senate Commerce, Science and Transportation Committee. It would apply a 2 percent tax to sales of television or radio stations if they had been owned more than three years, and 4 percent if the sale took place less than three years after purchase.

For the first two years, the money would go to the U.S. Treasury, and thereafter to public broadcasting. Those fees would rise by 1 percentage point if stations are found to have violated the Fairness Doctrine, the concept that stations must offer equal time to the different sides on controversial issues.

That makes the measure doubly objectionable to the broadcasters because it would place the doctrine in law for the first time.

Earlier this year, the Federal Communications Commission abolished the doctrine as unworkable. Congress fought back by putting it into law, only to have President Reagan veto the bill. Now Congress is trying again.

Sen. Ernest F. Hollings (D-S.C.), chairman of the Senate committee, said through a spokesman yesterday that he continues to believe in the station-transfer tax but is willing to consider the NAB's proposal. Rep. Edward J. Markey (D-Mass.), chairman of the House telecommunications and finance subcommittee, gave a similar response through a spokesman.

Rep. Al Swift (D-Wash.), a House subcommittee member, said that he might agree in principle with the NAB's idea, but that it should be more broadly based. He suggested that there be a tax on equipment manufacturers, cable operators and broadcasters to fund an endowment for public broadcasting. That way, he said, "you could put public broadcasting in a more stable position ... insulated even more from government and congressional interference."

The Media Access Project, a public-interest law firm dealing with media-access issues, condemned the NAB's idea. "Broadcasters have been freeloading for more than 50 years," said Andrew Schwartzman, the group's executive director. "Finally the bill is coming due and they're asking consumers to pick it up for them."