Sec.  90.261   Assignment and use of the frequencies in the band 450–470 MHz for
fixed operations.

   (a) Frequencies in the 450–470 MHz band as listed in  Sec. 90.20(c)(3) and
    Sec. 90.35(b)(3) may be assigned to all eligibles for fixed use on a secondary
   basis to land mobile operations.

   (b) Fixed stations located 140 km (87 mi) or more from the center of any
   urbanized area of 600,000 or more population are limited to a transmitter
   output power of 75 watts. Fixed stations less than 140 km (87 mi) from the
   centers of these areas are limited to a transmitter output power of 20
   watts. Urbanized areas of 600,000 or more population are defined in the U.S.
   Census of Population 1970, Vol. 1, Table 20, pages 1–74. The centers of the
   urbanized areas are determined from the Appendix, page 226, of the U.S.
   Department of Commerce publication “Airline Distance Between Cities in the
   United States.”

   (c) All fixed systems are limited to one frequency pair with 5 MHz spacing
   and must employ directional antennas with a front-to-back ratio of 15 dB,
   except that omnidirectional antennas having unity gain may be employed by
   stations communicating with a minimum of three receiving locations
   encompassed in a sector of at least 160 ° in azimuth. Stations authorized for
   secondary fixed operations prior to (effective date of the rules) may
   continue to operate under the conditions of their initial authorization.

   (d)–(e) [Reserved]

   (f) Secondary fixed operations pursuant to paragraph (a) of this section
   will not be authorized on the following frequencies or on frequencies
   subject to  Sec. 90.267:

   Frequencies (MHz)
   451.800/456.800
   451.80625/456.80625
   451.8125/456.8125
   451.81875/456.81875
   452.525
   452.53125
   452.5375
   452.54375
   452.550
   452.55625
   452.5625
   452.56875
   452.575
   452.58125
   452.5875
   452.59375
   452.600
   452.60625
   452.6125
   452.61875
   452.925/457.925
   452.93125/457.93125
   452.9375/457.9375
   452.94375/457.94375
   452.950/457.950
   452.95625/457.95625
   452.9625/457.9625
   452.96875/457.96875
   453.025/458.025
   453.03125/458.03125
   453.0375/458.0375
   453.04375/458.04375
   453.075/458.075
   453.08125/458.08125
   453.0875/458.0875
   453.09375/458.09375
   453.125/458.125
   453.13125/458.13125
   453.1375/458.1375
   453.14375/458.14375
   453.175/458.175
   453.18125/458.18125
   453.1875/458.1875
   453.19375/458.19375
   454.000/459.000
   454.00625/459.00625
   454.0125/459.0125
   454.01875/459.01875
   462.950/467.950
   462.95625/467.95625
   462.9625/467.9625
   462.96875/467.96875
   462.975/467.975
   462.98125/467.98125
   462.9875/467.9875
   462.99375/467.99375
   463.000/468.000
   463.00625/468.00625
   463.0125/468.0125
   463.01875/468.01875
   463.025/468.025
   463.03125/468.03125
   463.0375/468.0375
   463.04375/468.04375
   463.050/468.050
   463.05625/468.05625
   463.0625/468.0625
   463.06875/468.06875
   463.075/468.075
   463.08125/468.08125
   463.0875/468.0875
   463.09375/468.09375
   463.100/468.100
   463.10625/468.10625
   463.1125/468.1125
   463.11875/468.11875
   463.125/468.125
   463.13125/468.13125
   463.1375/468.1375
   463.14375/468.14375
   463.150/468.150
   463.15625/468.15625
   463.1625/468.1625
   463.16875/468.16875
   463.175/468.175
   463.18125/468.18125
   463.1875/468.1875
   463.19375/468.19375

   [ 57 FR 24992 , June 12, 1992, as amended at  58 FR 33212 , June 16, 1993;  60 FR 37268 , July 19, 1995;  62 FR 18928 , Apr. 17, 1997;  68 FR 19461 , Apr. 21,
   2003]