Sec.  22.371   Disturbance of AM broadcast station antenna patterns.

   Public Mobile Service licensees that construct or modify towers in the
   immediate vicinity of AM broadcast stations are responsible for measures
   necessary to correct disturbance of the AM station antenna pattern which
   causes operation outside of the radiation parameters specified by the FCC
   for the AM station, if the disturbance occurred as a result of such
   construction or modification.

   (a) Non-directional AM stations. If tower construction or modification is
   planned within 1 kilometer (0.6 mile) of a non-directional AM broadcast
   station tower, the Public Mobile Service licensee must notify the licensee
   of the AM broadcast station in advance of the planned construction or
   modification. Measurements must be made to determine whether the
   construction or modification affected the AM station antenna pattern. The
   Public Mobile Service licensee is responsible for the installation and
   continued maintenance of any detuning apparatus necessary to restore proper
   non-directional performance of the AM station tower.

   (b) Directional AM stations. If tower construction or modification is
   planned within 3 kilometers (1.9 miles) of a directional AM broadcast
   station array, the Public Mobile Service licensee must notify the licensee
   of the AM broadcast station in advance of the planned construction or
   modification. Measurements must be made to determine whether the
   construction or modification affected the AM station antenna pattern. The
   Public Mobile Service licensee is responsible for the installation and
   continued maintenance of any detuning apparatus necessary to restore proper
   performance of the AM station array.