New Rules for Activity Near AM Towers

This article summarizes proposed new FCC rules that apply to any municipality that is looking to build a new tower (such as a water tower or cell equipment tower) near an existing AM tower, to change an existing tower’s height, or to add or replace antennae or transmission lines on a tower. As of this article’s date, the rules have not yet taken effect, but it appears likely the rules will take effect very soon.  The FCC released a draft of its proposed rules. This article summarizes the draft rules.

Background

In AM radio, the tower itself is the antenna.  So, putting a new tower near an AM tower may distort the AM station’s signal. To guard against that distortion, the FCC proposed new rules to protect AM stations from distortion caused by nearby tower work. The proposed rules relate to requirements on broadcast and wireless entities, but since many municipalities own cell towers on which wireless entities locate antennae and change antennae, municipalities should be aware of the new rules, too and make sure they comply. 

Existing FCC rules on work near AM stations specify fixed distances within which work is presumed to affect the AM station.  The new rules would require notice to AM station owners and others when certain work is done within a set distance of an AM station.  Warning: some of the new rules are very technical, including the ways to measure “safe” distances from the towers.  But a municipal engineer should be familiar with these concepts and easily do the needed calculations and likely should be consulted if there is work on a municipal-owned tower that is near an AM station.

Summary of Proposed Rules

• Purpose of the Proposed Rules.  Parties proposing to build or modify a tower that is near an AM station are responsible for taking precautions to avoid distorting the AM station’s signal. 
• Proposed Rules for construction near a non-directional (single antenna) AM station.  You must give notice to the AM station owner 30 days in advance whenever there is proposed construction or significant modification of a tower that is (a) one wavelength away from the AM station, and (b) taller than 50 electrical degrees at the AM frequency.  The new rules specifically define “significant modification” and describe the type of notice to be given.
• Proposed Rules for construction near a directional (multiple antennas) AM station.  You must give notice to the AM station owner at least 30 days in advance for all proposed construction or significant modification of a tower that is (a) within the lesser of 10 wavelengths or 3 kilometers of the AM station, and (b) is taller than 36 electrical degrees at the AM frequency.
• Those proposing to build or modify a tower that falls within the distances listed above must examine the potential effects of their actions using the “moment method” analysis (yes, another area for the engineer to chime in on).     

If you have any questions about the new proposed FCC Rules, or work near an AM station tower, please contact Ron Richards at rrichards@fosterswift.com or 517.371.8154. 

• November 2013 Municipal Law News