Sec.  90.729   Limitations on power and antenna height.

   (a) The permissible effective radiated power (ERP) with respect to antenna
   heights for land mobile, paging, or fixed stations transmitting on
   frequencies in the 220–221 MHz band shall be determined from the following
   Table. These are maximum values and applicants are required to justify power
   levels requested.

                    ERP vs. Antenna Height Table \2\
------------------------------------------------------------------------
                                                               Effective
                                                                radiated
     Antenna height above average terrain (HAAT), meters         power,
                                                               watts \1\
------------------------------------------------------------------------
Up to 150....................................................        500
150 to 225...................................................        250
225 to 300...................................................        125
300 to 450...................................................         60
450 to 600...................................................         30
600 to 750...................................................         20
750 to 900...................................................         15
900 to 1050..................................................         10
Above 1050...................................................          5
------------------------------------------------------------------------
\1\ Transmitter PEP shall be used to determine ERP.
\2\ These power levels apply to stations used for land mobile, paging,
  and fixed operations.

   (b) The maximum permissible ERP for mobile units is 50 watts. Portable units
   are considered as mobile units. Licensees operating fixed stations or paging
   base stations transmitting on frequencies in the 221–222 MHz band may not
   operate such fixed stations or paging base stations at power levels greater
   than 50 watts ERP, and may not transmit from antennas that are higher than 7
   meters above average terrain, except that transmissions from antennas that
   are higher than 7 meters above average terrain will be permitted if the
   effective radiated power of such transmissions is reduced below 50 watts ERP
   by 20 log[10](h/7) dB, where h is the height above average terrain (HAAT),
   in meters.

   (c) Base station and fixed station transmissions on base station transmit
   Channels 196–200 are limited to 2 watts ERP and a maximum antenna HAAT of
   6.1 meters (20 ft). Licensees authorized on these channels may operate at
   power levels above 2 watts ERP or with a maximum antenna HAAT greater than
   6.1 meters (20 ft) if:

   (1) They obtain the concurrence of all Phase I and Phase II licensees with
   base stations or fixed stations receiving on base station receive Channels
   1–40 and located within 6 km of their base station or fixed station; and

   (2) Their base station or fixed station is not located in the United
   States/Mexico or United States/Canada border areas.

   [ 62 FR 15996 , Apr. 3, 1997, as amended at  63 FR 32590 , June 12, 1998]