RCA researchers have developed a new form...

RCA researchers have developed a new form of so-called high-definition television that they say is comparable in quality to the Japanese system but could be used by broadcasters with existing equipment, RCA and NBC officials announced. The system, developed at the David Sarnoff Research Center, still requires at least several years more development work, researchers said. But they said it offers new hope to U.S. broadcasters who have feared that the advent of a Japanese technology called “Muse” will make current television pictures look low-quality by comparison.