Sec.  90.637   Restrictions on operational fixed stations.

   (a) Except for control stations, operational fixed operations will not be
   authorized in the 806–824 MHz, 851–869 MHz, 896–901 MHz, or 935–940 MHz
   bands. This does not preclude secondary fixed tone signaling and alarm
   operations authorized in  Sec. 90.235 or in paragraph (c) of this section.

   (b) Control stations associated with one or more mobile relay stations will
   be authorized only on the assigned frequency of the associated mobile
   station. Use of a mobile service frequency by a control station of a mobile
   relay system is subject to the condition that harmful interference shall not
   be caused to stations of licensees authorized to use the frequency for
   mobile service communications.

   (c) Trunked and conventional systems that have exclusive-use status in their
   respective geographic areas may conduct fixed ancillary signaling and data
   transmissions subject to the following requirements:

   (1) All operations must be on a secondary, non-interference basis to the
   primary mobile operation of any other licensee.

   (2) The output power at the remote site must not exceed 30 watts.

   (3) Any fixed transmitters will not count toward meeting the mobile loading
   requirements nor be considered in whole or in part as a justification for
   authorizing additional frequencies in the licensee's mobile system.

   (4) Automatic means must be provided to deactivate the remote transmitter in
   the event the carrier remains on for a period in excess of three minutes.

   (5) Operational fixed stations authorized pursuant to the provisions of
   paragraphs (c) and (d) of this section are exempt from the requirements of
    Sec.  Sec. 90.425 and 90.429.

   (d) Conventional systems that do not have exclusive-use status in their
   respective geographic areas may conduct fixed ancillary signaling and data
   transmissions only in accordance with all the provisions of  Sec. 90.235.

   [ 47 FR 41032 , Sept. 16, 1982, as amended at  48 FR 51929 , Nov. 15, 1983;  49 FR 36377 , Sept. 17, 1984;  51 FR 37405 , Oct. 22, 1986;  52 FR 1332 , Jan. 13,
   1987;  53 FR 12157 , Apr. 13, 1988;  57 FR 34693 , Aug. 6, 1992]