§ 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
   Antenna height above average terrain (HAAT), meters Effective radiated
   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

   ^1Transmitter PEP shall be used to determine ERP.

   ^2These 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 log10(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]

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