Existing Home Antennas Suffice for DTV Converter Boxes

The program will fund 37.5 million coupons, each worth $40 toward a “certified” bare-bones converter box, pegged at costing $50 or less when analog service goes dark in less than 3 years. A household may qualify for 2 coupons by certifying it relies exclusively on over-the-air TV reception -- no FiOS, no cable, no satellite, no IPTV. NTIA’s rulemaking assumes the converter boxes will work with existing antennas, but said a GAO report last year cautioned there may be exceptions. The coupons are redeemable for a converter box but not an antenna upgrade.

The 37.5 million figure fits CEA estimates that only 13% of TV households -- 35 million sets -- are over-the-air only, requiring converter boxes, Jeff Joseph, CEA vp-communications & strategic relationships, said. CEA is confident few if any boxes will need special antennas, he said: “I pick up local DTV stations with a simple indoor antenna -- nothing fancy. As a rule of thumb, I push consumers to our antennaweb.org site to find the appropriate antenna.” The site, which makes recommendations based on geographical maps of signal strength, only addresses outdoor antennas -- not rabbit-ears or other indoor antennas. “Indoor antennas are not included in this mapping system because many variables determine the quality of reception in a specific location,” CEA said.

Despite that caveat, LG and Thomson maintain most over- the-air analog households won’t need to change antennas upon redeeming an NTIA coupon for a converter box or buying a step-up box without subsidy, they said. “Consumers who can receive terrestrial analog signals today can, in most cases, also receive digital TV signals without a significant change to their setup,” Thomson Vp Dave Arland said: “If a consumer has a rabbit-ears antenna arrangement today, then that same method of signal reception will likely work fine.”

Optimal DTV reception depends heavily on stations sending at full power, he said. “As more broadcasters have gone to full-power transmissions, it’s now easier to receive DTV signals in most cases,” Arland said: :Receiving digital signals is no more difficult than receiving analog signals, but there are obvious variances in power levels and even the locations of transmission antennas. Some broadcasters do not transmit digital signals from the same towers where they transmit analog signals.” In such cases, he said, households may need to reorient rooftop or set-top antennas, or upgrade to amplified models if transmitters are distant -- especially if the signal is UHF.

Multipath “ghosting” that marred early DTV reception no longer is a concern thanks to better tuner-chip knowhow, said LG Vp John Taylor. He agrees with Thomson, he said: “If you get a watchable NTSC analog picture now you should be able to get a crystal-clear digital picture with the same antenna. The same holds for the antenna farms on multiple dwelling units. If you're receiving only VHF signals now, you may have to go to a UHF bowtie, if the local broadcasters are using UHF to transmit.” Taylor, like others, noted a key difference between poor analog reception and its digital counterpart. A weak analog signal produces a snowy picture, but digital is an either/or -- “ perfect reception or none at all,” Taylor said. Like Arland, Taylor said DTV signal strength still is an issue, but much less than in the past. “Most broadcasters are at full power now,” he said, conceding that, for indoor antennas, “variables such as signal attenuation in the home, from aluminum siding and the like,” can influence antenna performance and require an upgrade.

Viewers with especially poor reception might consider the “SmartAntenna,” LG and Thomson said. “MSTV and NAB anticipated this, since their spec calls for use of the SmartAntenna interface,” Arland said: “This is a new feature that allows a set-top box to electronically steer a special external antenna, either on top of the TV or on the rooftop, without the need for manual rotors.” As defined by the IEC, “smart antenna” systems combine multiple antenna elements with digital signal-processing capability to optimize radiation or reception.

NTIA proposes including only a single RF Type-F antenna input on converter boxes certified for subsidy. Thomson and LG will include the SmartAntenna interface in their reference designs for MSTV-NAB. “While Thomson has incorporated that feature in the set-top boxes we will soon deliver to MSTV and NAB -- again, at their request -- it’s unknown whether or not those consumers who rely on terrestrial broadcasts will necessarily need this feature,” Arland said: “This feature requires a special interface on the set-top box, and a special antenna that responds to the commands.” The SmartAntenna cost isn’t known yet, but “it may be pricier than the set-top,” Arland said.

New antennas and upgrades will vary in price by type. We surveyed the Best Buy, RadioShack and Wal-Mart sites, finding amplified indoor antennas for $25-$70; passive models cost $10-$20. Amplified rooftop antennas ran $50- $150, passives $25-$40, not including installation. Best Buy’s site has a tutorial on DTV reception issues and highlights antennas for that purpose.

Terrestrial DTV reception problems seem more acute in the U.K., whose DTV switchover begins regionally in 2008, with final analog cutoff set for 2012. About of U.K. homes can’t get cable, and about 30% may need to upgrade their over-air antennas for DTV at an average cost of $235, authorities said. Factors: (1) Most U.K. homes have no rooftop antenna, making do with snowy pictures from set-tops. Poor analog reception could augur no DTV reception. (2) Elements on the indoor antennas might not be the right size to tune into DTV channel frequencies. Outdoor antenna elements might be aimed incorrectly for new DTV transmitter sites. (3) Coax down-leads may be corroded, further impeding reception of DTV at the set-top if transmission power is low. In the U.K., signal strength was a more serious problem when DTV launched there. Its COFDM transmission system since has made DTV signals more robust, but problems will persist there until full-power transmissions occur after analog cutoff.