Lawyers for NAB and the Media Access Project, representing the Prometheus Radio Project, faced off this week in oral arguments in a federal appeals court; the topic was low-power FM.

The National Association of Broadcasters is appealing a 2007 decision by the Federal Communications Commission to grant waivers to allow some LPFMs to remain on the air despite move-ins or power increases by full-power FMs. Granting the waivers violated the Radio Broadcasting Preservation Act, according to NAB.

In 2007, the commission allowed LPFMs to use a more accurate form of engineering criteria for predicting interference, according to the Prometheus Radio Project.

After the hearing, MAP Vice President Parul Desai said the agency was complying with the act when it granted the waivers.

In other LPFM news, a bill (S. 592) has been introduced in the Senate that would eliminate third-adjacent channel protection for full-power FMs to allow more LPFMs in the band; this is a companion bill to one already introduced in the House, as we've reported. Sen. Maria Cantwell, D-Wash., sponsors the Senate bill. This measure, too, creates a carve-out to exempt FMs carrying radio reading services.