Television viewers watching Channel 50 soon will see images that reflect changes in the Washington-area broadcasting industry.

As of Jan. 1, Channel 50 no longer will split its broadcast time between daytime commercial programming and nighttime subscription TV, called Super TV. Instead, the station will offer free commercial programming all the time, and subscribers to Super TV programs will have to tune into Channel 54, which broadcasts from Baltimore.

The changes reflect the end of one local broadcaster's dream, the sale of Channel 50 to a growing Dallas-based television company, and Super TV's adaptation to an evolving television market.

Washington entrepreneur Theodore Ledbetter launched station WCQR-TV, broadcasting over UHF Channel 50, in 1981 as one of a "new generation of television stations."

Ledbetter, an engineer, filmmaker and one-time station operator in the Virgin Islands, planned to use pay-TV to finance his own broadcasting dream.

Ledbetter, the station's majority owner, leased its prime-time hours to Subscription Television of Greater Washington, which broadcasts movies, concerts and special events via a scrambled picture signal. Viewers pay $49.95 for a decoding device to unscramble the signal and a monthly subscription fee of $19.95 for the basic service and $5.95 a month for late-night adult fare.

The subscription service, marketed as Super TV, is broadcast Monday through Friday from 7 p.m. to 2 a.m., and on weekends from 5 p.m. to 2 a.m.

Super TV also broadcasts from Channel 54 in Baltimore under a similar lease agreement.

Ledbetter hoped to fill the daytime hours with a variety of programming, broadcast without scrambling the signal. He promised to broadcast "free-form video," an eclectic mix of programs created by independent producers who have difficulty selling their works to conventional commercial stations.

At the time the station was launched, he said, "I'm not in it for the money. I'm a communicator who has had a difficult time getting stations to show my programs. We will see what people in the area come up with."

But the promises did not materialize into programs, and by late last year the station's daytime hours were dominated by Financial News Network reports.

Ledbetter's operation did not lose money, said Nolanda Hill, chairman of the Dallas-based media holding company that bought the station earlier this year for about $15 million.

But Ledbetter lacked the capital to accomplish his goals, said Hill and other local media analysts. "Given the resources he had, Ted did a phenomenal job," said Hill, chairman of Hill Broadcasting Inc. "But he started without much money, and without the ability to get money . . . and you need money to make money in this business."

Ledbetter, once the only black television-station operator in the local area, has since moved to Austin, Texas, where he has an unlisted number and could not be reached.

A Hill broadcasting subsidiary, once called Independent American Broadcasters of Washington, D.C., now owns the station. IAB has changed its name to WFTY Inc. and has changed the station's call letters to WFTY-TV.

The company paid about $7 million to the station owners and another $8 million to Super TV for its contractual rights to buy the station, Hill said.

After Jan. 1, Channel 50 will be a full-time commercial, independent station, offering movies, syndicated TV series and locally produced programs. Allen Ginsberg, former vice president and general manager of WTTG, Channel 5, has been hired to supervise programming and promotion. Robert D. Squier, the media consultant, is working with Hill to develop locally produced programs, she said.

"There is a lot of opportunity in Washington," Hill said. "This is one of the most glamorous and influential markets there is."

Hill Broadcasting was created last spring as a holding company for Nolanda Hill's growing string of television properties. A company she controls, Central Massachusetts Television, owns Channel 27 in Boston and is in the process of becoming a subsidiary of Hill Broadcasting. Hill also is general partner and majority owner of Dallas Women's Media Investors, a partnership that is applying for the license for Channel 55 in Dallas and plans to turn it into the only Spanish-language TV station in that city.

Hill Broadcasting hopes to buy three other stations in the next two years, and now has an appraised value of $80 million -- double the value 10 months ago, she said. The company is now in the red because of its acquisition and heavy investments in programming, personnel and equipment. But the company hopes to break even within two years, she said.

"We hope to dispel some myths," said Hill, whose company has actively sought to place women and members of minority groups in management positions. "We want to bring into the mainstream the idea that women can be financed, can bring in investors, can own and operate a television chain, and can do it in the market that is the most influential."

Super TV, meanwhile, will be available to Washington-area residents on Channel 54, said Thomas C. Thompson, president of Subscription Television of the Greater Washington Area, a joint venture between Field Communications Inc., a subsidiary of Field Enterprises Inc., the media conglomerate, and Subscription Television of America, controlled by Texas businessman Clinton W. Murchison Jr.

Super TV is sending technicians to local subscribers' homes to adjust antennas and replace the old decoder boxes with new ones that will unscramble Channel 54's signal.

About 20 percent, or 1,100 of Washington-area subscribers, will not be able to get the Channel 54 signal, Thompson said. Subscribers living in the far areas of Virginia, in hilly terrain or in buildings facing the wrong way will be unable to convert, he said.

Super TV is "quite a success" for an interim service with a declining subscriber base, Thompson said. About 28,000 viewers in Baltimore and Washington now subscribe, down from a peak of 78,000 in late 1983.

Locally, Super TV is profitable and plans to stay in business for at least five years, said Thompson. "Subscription television is an interim technology. . . . It was never intended to be a 40-year business."

Subscription television was conceived as a way to provide viewers with extra programming until cable, microwave transmission, and other new technologies were available.

"It was always seen as a transition service, to serve during the window of time while the nation was getting cable," said Andrew J. Schwartzman, executive director of the Media Access Project, a public-interest law firm.