NAB and the Association for Maximum Service Television (MSTV) sent a new video to Capitol Hill last Thursday demonstrating the potential interference that could result from introducing unlicensed mobile devices into broadcast television spectrum.

The video, which includes highlights from recent sporting events, shows the interference viewers would encounter if broadcast television spectrum is not afforded adequate protections.

"Despite what some high tech companies might tell you, this is what you can expect if unlicensed mobile devices are allowed to operate in the TV spectrum without adequate protections. These devices can't sense when spectrum is in use -- and we can't risk uncontrollable TV interference," the video reads.

The video is available at www.interferencezones.com/whitespaces.wmv.

Joining television broadcasters in expressing concern over the interference-causing devices are sports leagues, Broadway theater groups, cable operators and networks, wireless microphone manufacturers and religious groups.

A July 2007 FCC report concluded that sample prototype 'white space' devices did not accurately detect broadcast signals and caused interference to TV broadcasting and wireless microphones. That setback was followed by a February 2008 power failure, in which a Microsoft representative admitted that their prototype device "just stopped working." In March, another Microsoft device "unexpectedly shut down," according to a Microsoft press release.

To date, 70 lawmakers have expressed concern over the use of unlicensed personal-portable devices in the broadcast spectrum.