AM radio technical rules

The FCC’s proposals for aiding AM radio have been released in a Notice of Proposed Rulemaking – one of the last actions for broadcasters under Acting FCC Chairman Mignon Clyburn (see our article here on the leftover broadcast issues with which her successor as chairman, Tom Wheeler, will have to deal).  The proposals for revitalizing the AM band that were contained in the NPRM are all ones that the Acting Chair had previewed at the NAB Radio Show, which we summarized in our article about that speech.  While the general proposals that were made in the NPRM were not surprising, in most of these areas there were a couple of surprises in the details – some of which will may be of concern to some broadcasters.

The Commission made several proposals, including the following:

  • A special FM translator window where applications would be restricted to AM licensees.
  • Reduction of both daytime and nighttime city-grade coverage obligations of existing AM stations.
  • Elimination of the ratchet rule that requires that any AM station making facilities changes do so in a way that reduces overall interference in the AM band (in many cases compelling a reduction of service if a change is proposed)
  • The potential for more liberal use of MDCL technologies, which decrease transmitter power when modulation of the station decrease, potentially saving power (though raising some questions about the robustness of the signal that will result)
  • The modification of AM efficiency standards in some way to allow for shorter towers that could be located on rooftops or in other more limited spaces – though the Commission asked for more comments on how its current rules actually limited such uses
  • A general request for other ideas that could help AM stations.

We will cover the special translator window in today’s post, and cover the other issues in more detail in the future.  Most of the other proposals deal with making facilities changes to the AM station, in some cases changes that might actually decrease service to their current service areas (e.g. were some stations to take advantage of the proposed city-coverage limitation to move further from the station’s city of license).  The translator proposal is the one most likely to bring the most relief to the most AM broadcasters in the heart of their service area – and is one that can be quickly implemented.  So below, we will look at the translator proposal in more detail. 
Continue Reading FCC Proposals For AM Improvements – Part 1 – A Restricted FM Translator Window and an End to the Mattoon Waiver?