What Happened to My Station?
It’s been good season for tropospheric ducting along the New England shore. You might not be familiar with the term “tropospheric ducting,” but you just might have experienced it and not known why.
We’re all familiar with the way that AM signals bounce at night and come down far from their point of origin. Anyone who has listened to the big 50,000 Watt clear channel AMs knows the thrill of hearing a distant AM on a regular radio. I was once surprised to hear WBZ from Boston while in a traffic jam one night in Atlanta, Georgia. An AM station’s “skywave” component reflects off the ionosphere as it cools down at night and the usually transparent-to-AM layer turns reflective and the AM signal comes back to earth far from it’s transmitter. Frequency and tower height influence the degree of skywave along with seasonal differences and weather conditions.
As is well known by now, the FCC at last has finalized its plan to address the backlog of about 6,500 FM translator applications that still linger from a March 2003 filing window and to open a new filing opportunity for Low Power FM (“LPFM”) stations.
The FCC’s task was both prodded and complicated by the Local Community Radio Act of 2010 (the “LCRA”), which required that it balance translator grants against the need for preserving filing opportunities for new LPFMs. In resolving the choice between the two media, the five commissioners made it clear that the FCC overwhelmingly favors LPFM as holding a promise to expand locally originated service to narrow constituencies.
The FCC recently released the latest rules changes for LPFM Radio. Recnet has provided an overview of the FCC’s Fifth Order on Reconsideration and Sixth Report and Order on Low Power FM.
Section 7(1) stations (those that do not meet the second/third adjacent spacing in 73.807) must eliminate any actual interference they may cause to the signal of any authorized station in areas where that station is “regularly used” (same rules as translators).
Section 7(3) stations (all LPFM stations) must address complaints of third adjacent channel interference within the affected station’s protected contour.
Third adjacent channel protections remain in effect in respect to foreign FM stations and assignments as well as FM stations that are operating a radio reading service for the blind.