Led by the NAB and the MSTV, broadcasters today launched a lobbying blitz in Washington aimed at keeping the broadcast spectrum free of unlicensed wireless devices that they claim would interfere with their broadcast of HD and other digital services.

At a press conference at NAB headquarters this morning, a contingent of broadcasters and their Washington reps said they would visit FCC Chairman Kevin Martin and the other FCC commissioners this afternoon to press their case.

The broadcasters also said that they would begin airing spots on all Washington, D.C,, TV stations and running ads in Capitol Hill newspapers to influence the growing debate. The TV spots urge viewers to "tell Congress not to allow unlicensed devices on digital TV channels."

“The future of our business depends on our viewers receiving interference-free signals,” said Liz Burns of Morgan Murphy Stations and chair of the MSTV.

“The idea that low-grade interference is not a problem is just goofy,” said Alan Frank, of Post-Newsweek and chairman of the NAB TV board. “This interference will cause a consumer revolt; it will cause chaos.”

Blocking the unlicensed devices is now a top priority of NAB, said President David Rehr. NAB will “spend what it takes to achieve success.”

Joining the broadcasters in their campaign is the Sports Technology Alliance represented at the press conference by Jeff Willis of ESPN Productions. Sports and other event producers use the spectrum for licensed wireless microphones and, like broadcasters, fear interference.

The issue pits broadcasters against leading computer and Internet firms like Google, Microsoft, Dell, HP and Intel, now organized as the White Spaces Coalition.

The coalition contend that the white space—unused guard bands between broadcast channels—can be put to good use especially in rural areas as spectrum for laptops, PDAs and other unlicensed wireless devices that coalition members would sell or support.

Sensing technology in the devices will automatically detect broadcast signals it may interfere with and switch to signals it will not, the coalition claims.

The coalition suffered a setback in August when the FCC’s Office of Engineering and Technology issued the results of testing of white space prototypes and found them wanting.

The prototypes “do not consistently sense or detect TV broadcast or wireless microphone signals,” the FCC says in its report. “Our tests also found that the transmitter in the prototype device is capable of causing interference…”

Microsoft, which built the prototypes, asked the FCC to retest them, saying that they worked well during in-house tests and were malfunctioning during the FCC tests.

Not so fast, the broadcasters shot back. Microsoft is not entitled to an FCC do-over, they said

“If you can’t detect, you must reject,” said MSTV’s David Donovan at the press conference.

In addition to Rehr, Donovan, Frank and Burns, broadcasters on hand for the press conference and expected to visit the FCC include Jack Sander, Belo; Anne Sweeney, ABC; Jack Abernethy, Fox; John Wallace, NBC; Marci Burdick, Schurz; Scott Blumenthal, LIN Television; Vincent Sadusky, LIN Television; Mike Fiorile, Dispatch Broadcast; and Rob Hubbard, Hubbard Broadcasting.

"It is disingenuous for companies like Microsoft and Intel to insinuate that broadcasters oppose new technology," Rehr told reporters. "Broadcasters support rural broadband through a fixed service. The issue is whether these not-yet-invented devices should be deployed at the expense of broadcast television. We think such a move would be wrongheaded."