For years, the newspaper and the television set have been competitors, each striving to exploit its natural advantages in order to become consumers' main source of news.

Within two weeks, these competing media will merge, in a small way, when The Washington Post becomes part of an experiment in which news and other information will be broadcast over the airwaves and available on television sets in 40 homes and 10 public places specially equipped with keypads and decoders.

The broadcast won't be a typical television news program, with anchor persons, reporters, cameras and sound. Instead, it will be a broadcast of words, in text form, that will appear on the television screen in as many as 15 different colors.

The experiment is called Teletext, and is sponsored by New York University's Alternate Media Center. The television sets, decoders and keypads are being placed in homes in Chevy Chase, Adams-Morgan and Anacostia, and in public places that include the Martin Luther King Library in Washington, the Jewish Community Center in Rockville, the National Press Club, Walt Whitman High School in Bethesda, the Children's Museum, and the Smithsonian's Museum of Science and Technology.

News from The Post, and other information supplied by the New York Daily News, the D.C. Public Library, the National Weather Service, the Washington Consumser Checkbook and several other organizations, will be fed to WETA's broadcasting facility in Shirlington via a computer hookup.

Simultaneous with its regular television broadcasts, WETA will broadcast the Teletext service in a section of the broadcast spectrum called the vertical blanking interval. The Vbi exists in every television broadcasting operation. It is that horizontal black band you see between frmes on your television set when you're trying to use the vertical hold button to stop your picture from rolling. More technically, the VBI is a part of the broadcast band that is not used in normal broadcasts, but it used, for example, to provide closed captioning for the deaf.

Pat Quarles, the Alternate Media Center's site manager for the Teletext project, explained that its purpose is "to examine the user issues, to try to see in what ways the service is good for the general public. We want to know what kind of information is of use to the people in this kind of mode, what factors in design and important, how much this all costs, and what kinds of people use it the most."

Post stories sent over the Teletext system will not be the full-length versions of the stores that appear in the daily newsapaper. The Post instead will provide specially edited synnopses of up to 10 different stories each day, and information about them. The Post also will provide sports scores and a weekly feature of the system.

Teletext is the Post's second experiment in delivering its information to people's homes by means other than newsprint. The first is CompuServe, an Ohio-based news and information service through their home computers. While CompuServe and Teletext both will bring news to the home electronically, there are significant differences between them. First, information form CompuServe is sent out over telephone lines and received on home computer screens, while Teletext is broadcast over the airways and received on television sets.