Sec.  27.64   Protection from interference.

   Wireless Communications Service (WCS) stations operating in full accordance
   with applicable FCC rules and the terms and conditions of their
   authorizations are normally considered to be non-interfering. If the FCC
   determines, however, that interference which significantly interrupts or
   degrades a radio service is being caused, it may, after notice and an
   opportunity for a hearing, require modifications to any WCS station as
   necessary to eliminate such interference.

   (a) Failure to operate as authorized. Any licensee causing interference to
   the service of other stations by failing to operate its station in full
   accordance with its authorization and applicable FCC rules shall discontinue
   all transmissions, except those necessary for the immediate safety of life
   or property, until it can bring its station into full compliance with the
   authorization and rules.

   (b) Intermodulation interference. Licensees should attempt to resolve such
   interference by technical means.

   (c) Situations in which no protection is afforded. Except as provided
   elsewhere in this part, no protection from interference is afforded in the
   following situations:

   (1) Interference to base receivers from base or fixed transmitters.
   Licensees should attempt to resolve such interference by technical means or
   operating arrangements.

   (2) Interference to mobile receivers from mobile transmitters. No protection
   is provided against mobile-to-mobile interference.

   (3) Interference to base receivers from mobile transmitters. No protection
   is provided against mobile-to-base interference.

   (4) Interference to fixed stations. Licensees should attempt to resolve such
   interference by technical means or operating arrangements.

   (5) Anomalous or infrequent propagation modes. No protection is provided
   against interference caused by tropospheric and ionospheric propagation of
   signals.