A New York company that shipped hard-core pornographic movies to Utah for satellite transmission to 30,000 homes pleaded guilty to a federal obscenity charge Thursday and will pay a $150,000 fine.

Federal obscenity charges were filed in Salt Lake City against Home Dish Only Satellite Networks Inc. Similar charges were filed against the company in Buffalo, N.Y. The company entered a guilty plea in a New York federal court.HDO began operating in 1986 on its American Exxxtasy Channel. The company used U.S. Satellite Inc. of Murray, Utah, to electronically transmit the broadcast signal to a GTE Spacenet Corp. satellite.

"They broadcast from Murray 12 hours a day, 365 days a year for several years," said Richard Lambert, assistant U.S. attorney.

The Murray company was not prosecuted because it cooperated with the investigation and shut down the transmissions last March, said Dee V. Benson, U.S. attorney in Utah. U.S. Satellite Inc. is a subsidiary of the Utah-based Skaggs Telecommunications Services Inc.

The satellite beamed the broadcast to individual subscribers throughout the continental United States, Lambert said. HDO charged $260 a year for subscription to the channel.

HDO's American Exxxtasy channel broadcast hard-core feature-length movies such as "Ramb-Ohh Sex Platoon" and "Hard-core Girlfriends."

The company's films and short movies were scrambled so they could only be received by subscribers. But the company advertised subscriptions to its American Exxxtasy Channel every night from 6 to 8 using commercials that displayed the explicit nature of the films available on the channel.

Those commercials were not scrambled and could be received by any satellite dish owner, Benson said.

In Buffalo, the company pleaded guilty to one felony count of transmitting an obscene promotional movie, "Hot Shorts," on Feb. 25, 1990, from Buffalo. It also agreed to plead guilty to a separate felony charge in Salt Lake City of transmitting the movie "Hard-core Girlfriends" the next day.

The "Hot Shorts" promotional films were beamed in the early evening to owners of satellite dish receivers to advertise the explicit nature of the films available from American Exxxtasy, the U.S. Department of Justice said.

Federal officials in Utah did not realize the hardcore movies were being transmitted to the satellite from Utah until a Montgomery, Ala., district attorney brought charges against HDO. U.S. Satellite Inc. and GTE, Lambert said. "After the Alabama investigation, we initiated our investigation."

Last month, HDO pleaded guilty to a state obscenity charge in Montgomery, Ala., and was fined $5,000.

HDO went out of business in March after a grand jury issued subpoenas that signaled a federal investigation, Benson said.

The investigation of HDO was the first conducted under a 1988 federal law prohibiting satellite and cable broadcasting of obscenity, Attorney General Dick Thornburgh said in a press statement Thursday.

HDO's two principal officers have agreed to refrain from distributing pornography in the future and will turn all pornographic tapes over to the Department of Justice for destruction, the statement said.