Participants in the high definition TV “grand alliance” told Congress Thursday that their decision to join forces should hasten HDTV delivery to U.S. consumers and that HDTV sets will easily “interoperate” with computers.The upbeat comments from representatives of AT&T, the David Sarnoff Research Center and General Instrument Corp. came at a hearing before Rep. Ed Markey’s (D-Mass.) House telecommunications subcommittee. Markey called the hearing to review the HDTV alliance’s impact on job creation in the U.S., and to explore whether HDTV sets will be compatible with computers. AT&T veepee Robert Graves called formation of the alliance “good news for everyone — consumers, broadcasters, cable operators, the computer and telecommunications industries, and the U.S. job market in general.” He said the alliance “can save a year or more in the implementation of HDTV” because it avoids “the risk of ambiguous test results” and also lessens the chance of lawsuits challenging the FCC’s final decision on whether to accept the alliance proposal. Graves said he expects the FCC will adopt a single HDTV standard by the end of 1994. The combined system will be promoted as the single HDTV standard throughout the world, according to Graves. Graves’ remarks were echoed by Sarnoff prez Dr. James Carnes and General Instrument VP Dr. Robert Rast. Carnes called the alliance “an exciting new model for corporate cooperation.” Not all of the witnesses were as bullish on the HDTV alliance. Prof. Nicholas Negroponte of the Massachusetts Institute of Technology claimed the U.S. is “about to make a terrible mistake” by not developing an international standard. Markey questioned the validity of Negroponte’s argument, however, claiming that the U.S. HDTV standard will likely be embraced by the world because it employs cutting-edge digital technology. Markey recalled that about six years ago, the U.S. was “woefully behind” the Japanese and others in the race to develop an HDTV standard. The all-digital HDTV format is a “tribute to American ingenuity” and “one of the great late-inning comebacks of all time,” Markey said. Also voicing skepticism over the HDTV alliance was John Abel, exec VP at the National Assn. of Broadcasters. Abel noted that broadcasters face a $ 10 million to $ 14 million price tag for converting to HDTV, and that advertisers won’t be paying more for their blurbs simply because they’re transmitted in HDTV. To help broadcasters offset the high cost of conversion, the FCC must permit TV stations to offer ancillary data transmission services, Abel said.