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Digital TV not ready for prime time

The esoteric issue of how to connect cable television set-top boxes to DTVs exemplifies the challenges for the new technology.

    The federal government, worried that technical and political imbroglios are stalling critical aspects of next-generation television, is calling on the consumer electronics and cable industries to ensure the transition from analog to digital technology.

    But getting the two industries to link up--literally and figuratively--is anything but easy. The seemingly esoteric issue of how to connect cable set-top boxes to digital TVs and receive the type of high-quality images that the technology affords exemplifies the many hurdles that stand before advanced digital broadcasting.

    The upshot: High-quality digital broadcasts are slated to begin in some U.S. markets this November, but its true benefits may not be available to millions of cable subscribers because feuding parties have yet to agree on a way to get those signals from the cable box to new, expensive digital TV sets.

    "It's a mess," said Gerry Kaufhold, principal digital TV analyst for Cahners In-Stat research group. "There are different industries involved. Each one has its own agenda, and none of them is moving in the same direction."

    The main problem is that new DTV sets, costing upwards of $5,000, can't directly receive digital signals from the cable set-top converter boxes now found in 65 percent of U.S. homes. As it stands, consumers will have to rely on antennas hooked up to their television sets to get DTV signals in their pristine, high-resolution state.

    Manufacturers are working on a separate "decoder" box that can translate the digital signal offered in a limited number of cable systems to a signal that the TV can understand, but this adds $1,000 to $3,000 to the purchase. A cost-effective solution for the problem is possible but faces huge obstacles.

    Federal Communications Commission chairman William Kennard recently sent a letter urging the two sides to work out how cable fits into the digital television picture. Kennard appears worried that IEEE 1394 technology for connecting cable set-top boxes to digital television sets, more commonly known as "FireWire," won't be available in the first generation of DTV.

    The move to digital television already is 11 years in the making, and government officials have grown weary of the fight over technical standards. Kennard exhorted the heads of the National Cable Television Association (NCTA) and Consumer Electronics Manufacturers Association (CEMA) to "work together to ensure that cable customers who purchase new sets this fall are able to enjoy the benefits of their investment in digital television."

    The NCTA declined to comment on Kennard's letter. A CEMA representative said the group is preparing a response but declined to comment. In an earlier response to inquiries from Congress, CEMA president Gary Shapiro said that the two industries are working on standards for "cable-ready" digital television sets, but that a variety of issues will remain unresolved by the start of DTV broadcasts this fall.

    TV format wars
    HDTV: high definition television

    1080i: Offers 1080 lines of resolution. Displays images using interlaced scanning, which first transmits all the odd lines on the TV screen and then the even lines. Supported by CBS, NBC.

    720p: Offers 720 lines of resolution. Displays images using progressive scanning, which transmits each line from top to bottom, which offers image quality close to that of 1080i. When transmitted at 24 frames per second instead of the usual 60 frames per second, cable operators can squeeze more HDTV channels into their lineup. Supported by ABC, Fox, cable operators.

    SDTV: standard definition television

    480p: Offers 480 lines of resolution scanned one after another onto the screen. Bandwidth friendly; allows for transmission of either multiple programs in the space of one channel, or data services such as Internet access. Supported by Microsoft, various computer companies.

    The problems don't end there. Analysts say the issue of connecting DTVs and set-top boxes is a sideshow compared with what are called "must-carry" rules, which would require cable operators to transmit high-definition television signals--a problem for them because this eats into allotted bandwidth set aside for regular broadcasting.

    "What happened was everyone was focusing on the more fundamental question of digital 'must carry,' then suddenly it occurred to people that even if the FCC mandated the carriage of all signals, the signals still couldn't get though because of all these compatibility issues," said Cynthia Brumfield, a cable industry analyst with Paul Kagan Associates.

    Affiliates of the four networks in the ten largest markets are slated to begin digital broadcasts no later than May next year and in the top 30 markets by November 1999. The FCC is attempting to promulgate rules that would guide the various parties through the transition from an analog to a digital-only broadcast world.

    Cable operators say that, if they are forced to carry both analog and digital broadcasts, they will have to drop many cable-only channels to make room for the multitude of signals, with the eventual result being a large loss of advertising and subscriber revenues.

    Even where cable companies such as Tele-Communications Incorporated have offered a version of digital service, the majority of set-top boxes won't have the appropriate chips to decipher the high-definition signals for at least two more years, Brumfield estimated.

    Services now marketed as "digital TV" by cable companies such as TCI are basically more channels on analog television. True digital TV, on the other hand, promises the ability to display content with greater picture quality than now possible.

    Consumer electronics manufacturers say they are working on DTV sets that can bridge the digital-analog gap. The TV would basically subsume the functions of the set-top box, except for the proprietary security functions a cable operator uses to ensure that no one can illegally copy or steal their signals. But industry standards for this technology have yet to be set.

    Despite the remaining hurdles, at least one expert in the field is hopeful. Josh Bernoff, principal digital television analyst with Forrester Research, predicts that the various parties will resolve their issues by next fall's mandated launch in the top 30 markets and have "cable-ready" sets capable of receiving the long promised high definition TV programming.

    Now, the devil is in the details.