Sec.  73.809   Interference protection to full service FM stations.

   (a) If a full service commercial or NCE FM facility application is filed
   subsequent to the filing of an LPFM station facility application, such full
   service station is protected against any condition of interference to the
   direct reception of its signal caused by such LPFM station that operates on
   the same channel, first-adjacent channel or intermediate frequency (IF)
   channel as or to such full service station, provided that the interference
   is predicted to occur and actually occurs within:

   (1) The 3.16 mV/m (70 dBu) contour of such full service station;

   (2) The community of license of such full service station; or

   (3) Any area of the community of license of such full service station that
   is  predicted  to receive at least a 1 mV/m (60 dBu) signal. Predicted
   interference shall be calculated in accordance with the ratios set forth in
    Sec. 73.215 paragraphs (a)(1) and (a)(2). Intermediate frequency (IF) channel
   interference overlap will be determined based upon overlap of the 91 dBu
   F(50,50) contours of the FM and LPFM stations. Actual interference will be
   considered  to  occur whenever reception of a regularly used signal is
   impaired by the signal radiated by the LPFM station.

   (b)  An LPFM station will be provided an opportunity to demonstrate in
   connection with the processing of the commercial or NCE FM application that
   interference as described in paragraph (a) of this section is unlikely. If
   the LPFM station fails to so demonstrate, it will be required to cease
   operations upon the commencement of program tests by the commercial or NCE
   FM station.

   (c)  Complaints  of  actual interference by an LPFM station subject to
   paragraphs (a) and (b) of this section must be served on the LPFM licensee
   and  the  Federal  Communications Commission, attention Audio Services
   Division. The LPFM station must suspend operations within twenty-four hours
   of the receipt of such complaint unless the interference has been resolved
   to the satisfaction of the complainant on the basis of suitable techniques.
   An LPFM station may only resume operations at the direction of the Federal
   Communications Commission. If the Commission determines that the complainant
   has refused to permit the LPFM station to apply remedial techniques that
   demonstrably will eliminate the interference without impairment of the
   original reception, the licensee of the LPFM station is absolved of further
   responsibility for the complaint.

   (d) It shall be the responsibility of the licensee of an LPFM station to
   correct any condition of interference that results from the radiation of
   radio frequency energy outside its assigned channel. Upon notice by the FCC
   to the station licensee or operator that such interference is caused by
   spurious  emissions  of the station, operation of the station shall be
   immediately  suspended and not resumed until the interference has been
   eliminated. However, short test transmissions may be made during the period
   of suspended operation to check the efficacy of remedial measures.

   (e) In each instance where suspension of operation is required, the licensee
   shall submit a full report to the FCC in Washington, DC, after operation is
   resumed, containing details of the nature of the interference, the source of
   the interfering signals, and the remedial steps taken to eliminate the
   interference.

   [ 65 FR 7640 , Feb. 15, 2000, as amended at  65 FR 67302 , Nov. 9, 2000;  73 FR 3216 , Jan. 17, 2008]