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Background and Initial Audience Characteristics of the Closed-Caption Television System Carl Jensema and Molly Fitzgerald Over the past four decades, television has become an important feature of the American culture. In this country there are more than 1,000 television stations broadcasting to well over 100 million television receivers . This network forms a massive system of entertainment and education for the American public. Unfortunately, many programs are meaningless without full audio comprehension , and the hearing impaired have been severely limited in the benefits they receive from television. This problem was recognized, and in 1973 the Bureau of Education for the Handicapped (BEH) began funding research through the Public Broadcasting Service (PBS) to develop a system for closed-captioning television programs . The goal was to create a system which would make hidden subtitles (closed captions) a part of regular television broadcasts. The captions would be visible only on those television receivers equipped with a special adapter. To understand how the system developed by PBS accomplishes closed captioning, it is necessary to have a basic understanding of how a television picture is generated. In the American system, a television picture consists of 525 lines flashed on the screen 30 times per second. The first few and the last few of the 525 lines are not used as part of the regular picture. They appear as the familiar black bar seen on a television receiver which needs adjustment. The PBS system involves broadcasting binarilycoded data on Line 21. An adapter hooked to a viewer's television receiver interprets the Line 21 signals and generates visible characters on the screen. By March 1979 the system was nearly ready. The United States Department of Health, EduBoth authors are associated with Gallaudet College in Washington, D. C. Carl Jensema is the Director of Research and Standards. cation, and Welfare (HEW) held a major press conference to announce that three national television networks (PBS, ABC, NBC) agreed to pay for and broadcast closed-captioned television programs beginning in 1980. HEW also announced that it was providing seed money to establish a nonprofit corporation, the National Captioning Institute (NCI), to caption programs. During the summer of 1979 NCI became a visible, functioning corporation. In September of that year it moved into its permanent home in Falls Church, Virginia. A Los Angeles office was opened in October 1979. John E. D. Ball, who had directed the closed-caption development at PBS as Vice President of Engineering, became President of NCI at the beginning of January 1980. On March 16,1980, the three networks began broadcasting a total of 16 hours of closedcaptioned programs each week. By the fall of 1980 this number had grown to 22V2 hours and was expected to keep expanding rapidly. Closed-caption adapters and television receivers with built-in closed-caption circuitry are assembled by Sanyo using Texas Instrument computer chips. The units are marketed by Sears, Roebuck and Co. Sears started accepting orders for adapters in January 1980 and began delivery in March. By the end of June nearly 21,000 adapters had been sold. Television receivers with closed-caption circuitry went on the market in July. With the exception of the first 3,700 adapters, every closed-caption adapter and integrated receiver manufactured has included a questionnaire postcard from NCI. This postcard contains various items relating to where the equipment will be used, who will watch, and what kinds of programs are preferred. The remainder of this report is concerned with a brief descriptive summary of the initial closed32 A.A.D. I February 1981 Background and Initial Audience Characteristics caption audience based on data from early questionnaire returns. Discounting the 3,700 adapters without postcards , roughly 17,000 questionnaires were distributed by the end of June 1980, exactly 6,182 of these were returned, approximately a 36% response rate. AU of the questionnaires represent add-on adapters, since the television receivers with built-in circuitry did not go on the market until July. Among the 6,182 questionnaires returned, 6,173 gave the home state of the adapter purchaser . Table 1 provides data on the number of questionnaires returned from each state. California leads with 702 questionnaires (11% of the total...

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