Sec.  90.305   Location of stations.

   (a) The transmitter site(s) for base station(s), including mobile relay
   stations, shall be located not more than 80 km. (50 mi.) from the geographic
   center of the urbanized area listed in  Sec. 90.303.

   (b)  Mobile  units  shall  be operated within 48 km. (30 mi.) of their
   associated base station or stations. Such units may not be operated aboard
   aircraft in flight except as provided for in  Sec. 90.315(i).

   (c) Control stations must be located within the area of operation of the
   mobile units.

   (d) Base and control stations shall be located a minimum of 1.6 km. (1 mi.)
   from local television stations operating on UHF TV channels separated by 2,
   3, 4, 5, 7, and 8 TV channels from the television channel in which the base
   station will operate.