Moving Stations to Lower Channels Seen Not Working for Mobile DTV

Going to VHF would work only for stations that don’t want to pursue mobile DTV, many industry officials said. Some were skeptical that moving even those stations not doing mobile DTV from the UHF to the VHF part of the TV band will work out well technically. For stations that want to send signals to mobile devices, the antenna size and power level that would be required for the consumer electronics gear to receive mobile DTV on VHF would be impractical, many said. The FCC said it doesn’t plan to force anyone to repack.

Stations fled the VHF band in the months after the 2009 DTV transition for all full-power broadcasters. Many stations that had been moved by the FCC to broadcast in the VHF band in digital, after the analog cutoff, received permission from the regulator to return to UHF. Currently, industry officials estimated there are about 40 TV stations operating in the low part of the VHF band, between channels 2 and 6. That’s said to be the worst part of the TV band for broadcasters. About 400 stations broadcast in the upper part of VHF, channels 7-13. The rest of the 1,781 full-power TV stations in the U.S. as of year’s end are in UHF.

It cost some stations millions of dollars to move back to UHF from VHF following the digital transition, executives estimated. Gray Television moved WKYT Lexington, Ky., and KKTV Colorado Springs, Colo., to UHF after the DTV transition, spending about $2 million in equipment costs at the Colorado station, said Technology Vice President James Ocon. The company now operates 43 stations. Sinclair Broadcast Group moved four of the 58 stations it owns or runs to UHF, said Advanced Technology Director Mark Aitken. They were among the TV station-group executives, whose companies collectively run more than 150 stations, to express some concern about broadcasting on VHF, and especially the lower part of that band.

"If a broadcaster’s got little intention of making mobile a big part of their future, then high V might be adequate to serve homes with,” said Aitken. “When it comes to mobile DTV and small handheld devices and tablets, etc., the physics of VHF just don’t work at all well for mobile DTV.” Portable devices that can be carried around by consumers need small antennas, and with the power levels that VHF stations can reasonably use in major markets, the antennas would have to be big because the power levels couldn’t be too high, Aitken and others said. In major markets on the coasts, the amount of interference created by a VHF station transmitting at a power level that’s sufficiently high for the broadcasts to be received on portable devices indoors would be too great, they said. Some proponents of moving to VHF, including at the FCC, have said higher power levels might help.

"Not so fast when you say raising power is the magic” pill, because you may not be allowed to because of an adjacent market where stations on similar channels might receive interference, Ocon said. “The metropolitan areas and areas that are adjacent and medium-sized markets, I think you are going to have trouble.” Upping power would “have minimal effect -- mobile performance suffers” and that could hurt the commercialization of the service, he added: “Raising power I think is a feeble attempt by the FCC to placate VHF performance” worries.

The FCC envisions that TV stations will be able to move voluntarily from UHF to VHF “in exchange for compensation” and “if they decide on their own that it makes good business sense for them to do so,” an agency spokesman said. “We have proposed to compensate stations for the direct costs of changing channels in a realignment of the band. This would be limited to stations moving from UHF to VHF. We are not contemplating changes in a station’s contour or viewer coverage area, unless they seek one."

Broadcasters that don’t want to move won’t need to, the spokesman said. And they can specify they want to go only to the upper part of the VHF band, he said. “Any station that offers to do that could specify if it is only willing to move into the upper VHF band. This is all predicated on whether Congress grants the commission the authority to go forward with incentive auctions. And even then, any legislation passed and signed into law may have specific parameters for the FCC to follow."

Broadcasting in the upper part of the VHF band ought to pose no problem for regular broadcasting operations, some industry executives and technical consultants said. “Moving back to the low band is unacceptable, but moving back to the high-band Vs is acceptable” as long as a station’s coverage area isn’t unduly limited by going to VHF, said a station-group executive. “In Boston it is a bad idea because there may not be space for it” given many frequencies are already used by TV stations, the executive said: In other, large markets, “you may have to protect too much from interference to others to do it at sufficient power.” Channels 7-13 are the best for traditional DTV, the executive said.

Cox Media Group “certainly” is “concerned about any of the proposals” in an FCC rulemaking notice “that would negatively impact the ability of our viewers to receive high-quality over-the-air signals,” such as repacking UHF stations to the VHF band, a spokesman said. Others in the industry have more forcefully spoken out against repacking’s potential harms. “We don’t want to be moved into a band that is lower power, so we lose viewership,” NAB President Gordon Smith said recently. FCC Commissioner Robert McDowell said Smith’s concerns were all “legitimate,” speaking at a recent NAB gathering, where the two were on stage. Smith then worried aloud about a station that didn’t want to volunteer to sell its spectrum in the mobile futures auction envisioned by FCC Chairman Julius Genachowski and others. “Does he get pushed into the VHF band?” And “is the signal strength what it was, can he still do mobile” broadcasting, Smith also asked.

For mobile DTV, the high part of the VHF band isn’t an option, agreed several technical consultants to TV-station groups. “High V isn’t going to work for mobile DTV,” said Vice President Richard Mertz of Cavell Mertz. That requires a larger antenna than most devices can handle, “and trying to fit a larger antenna into a handheld isn’t easy,” he added. “It’s not impossible, but it’s difficult.”

Mobile DTV on high-band VHF would work on devices installed in autos, not portable ones, said broadcast technical consultant Merrill Weiss, who played a major role in developing systems to distribute digital signals throughout a service area. A device in a car or truck is “rather limiting in where and how it can be used,” he said. “In terms of providing mobile and handheld together, high VHF is still problematic.”