About 86 FM stations now have increased their digital power, according to the National Association of Broadcasters.
This chart from NAB shows the distribution of the power level increases among FMs that have raised digital power. The NAB’s Radio Tech Check newsletter this week searched the FCC’s Consolidated Database System Electronic Filing System and arrived at that number. The search turned up 51 commercial and 35 noncommercial stations that have raised their HD Radio power level.
In late January the FCC authorized stations to operate with digital power levels in excess of the previous limit of 1% (–20 dBc) of analog signal power level.
After May 10, stations could simply notify the agency that they were transmitting at elevated power, rather than apply for an STA. Shortly after that date, Radio World counted some 40 FMs operating with elevated power. At that time, most had implemented increases of 6 dB, to 14 dB below carrier, or less.
The NAB figures appear to confirm that trend. The majority of stations are operating at –14 dBc, the “blanket” authorized power level for most stations.
The NAB found that seven FMs are operating in excess of –14 dBc, with six of these having increased to the maximum allowed –10 dBc. Thirty-seven percent of stations operating at elevated digital power levels are operating below the –14 dBc blanket authorization value. NAB surmises that many of those stations increased digital power only as much as their current facilities would allow.
FM stations planning to increase their digital power should refer to a Public Notice (PDF) released by the Media Bureau on May 17 for guidance.