§ 74.1235   Power limitations and antenna systems.

   (a) An application for an FM translator station filed by the licensee or
   permittee of the primary station to provide fill-in service within the
   primary  station's coverage area will not be accepted for filing if it
   specifies an effective radiated power (ERP) which exceeds 250 watts.

   (b) An application for an FM translator station, other than one for fill-in
   service which is covered in paragraph (a) of this section, will not be
   accepted for filing if it specifies an effective radiated power (ERP) which
   exceeds the maximum ERP (MERP) value determined in accordance with this
   paragraph.  The  antenna  height above average terrain (HAAT) shall be
   determined in accordance with § 73.313(d) of this chapter for each of 12
   distinct radials, with each radial spaced 30 degrees apart and with the
   bearing of the first radial bearing true north. Each raidal HAAT value shall
   be rounded to the nearest meter. For each of the 12 radial directions, the
   MERP is the value corresponding to the calculated HAAT in the following
   tables  that is appropriate for the location of the translator. For an
   application specifying a nondirectional transmitting antenna, the specified
   ERP  must not exceed the smallest of the 12 MERP's. For an application
   specifying a directional transmitting antenna, the ERP in each azimuthal
   direction  must  not  exceed the MERP for the closest of the 12 radial
   directions.

   (1) For FM translators located east of the Mississippi River or in Zone I-A
   as described in § 73.205(b) of this chapter:
       Radial HAAT (meters)     Maximum ERP (MERP in watts)
   Less than or equal to 32                             250
   33 to 39                                             170
   40 to 47                                             120
   48 to 57                                              80
   58 to 68                                              55
   69 to 82                                              38
   83 to 96                                              27
   97 to 115                                             19
   116 to 140                                            13
   Greater than or equal to 141                          10

   (2) For FM translators located in all other areas:
       Radial HAAT (meters)     Maximum ERP (MERP in watts)
   Less than or equal to 107                            250
   108 to 118                                           205
   119 to 130                                           170
   131 to 144                                           140
   145 to 157                                           115
   158 to 173                                            92
   174 to 192                                            75
   193 to 212                                            62
   213 to 235                                            50
   236 to 260                                            41
   261 to 285                                            34
   286 to 310                                            28
   311 to 345                                            23
   346 to 380                                            19
   381 to 425                                          15.5
   426 to 480                                            13
   481 to 540                                            11
   Greater than or equal to 541                          10

   (c) The effective radiated power of FM booster stations shall be limited
   such that the predicted service contour of the booster station, computed in
   accordance with § 73.313 paragraphs (a) through (d) of this chapter, may not
   extend beyond the corresponding service contour of the primary FM station
   that the booster rebroadcasts. In no event shall the ERP of the booster
   station exceed 20% of the maximum allowable ERP for the primary station's
   class.

   (d) Applications for FM translator stations located within 320 km of the
   Canadian border will not be accepted if they specify more than 50 watts
   effective radiated power in any direction or have a 34 dBu interference
   contour, calculated in accordance with § 74.1204 of this part, that exceeds
   32 km. FM translator stations located within 320 kilometers of the Mexican
   border  must  be  separated from Mexican allotments and assignments in
   accordance  with  § 73.207(b)(3)  of  this chapter and are limited to a
   transmitter power output of 10 watts or less. For purposes of compliance
   with that section, FM translators will be considered as Class D FM stations.

   (1) Translator stations located within 125 kilometers of the Mexican border
   may operate with an ERP up to 50 watts (0.050 kW) ERP. A booster station may
   not  produce  a 34 dBu interfering contour in excess of 32 km from the
   transmitter site in the direction of the Mexican border, nor may the 60 dBu
   service contour of the booster station exceed 8.7 km from the transmitter
   site in the direction of the Mexican border.

   (2) Translator stations located between 125 kilometers and 320 kilometers
   from the Mexican border may operate with an ERP in excess of 50 watts, up to
   the maximum permitted ERP of 250 watts per § 74.1235(b)(2). However, in no
   event shall the location of the 60 dBu contour lie within 116.3 km of the
   Mexican border.

   (3) Applications for translator or booster stations within 320 km of the
   Canadian border may employ an ERP up to a maximum of 250 watts, as specified
   in § 74.1235(a) and (b). The distance to the 34 dBu interfering contour may
   not exceed 60 km in any direction.

   (e) In no event shall a station authorized under this subpart be operated
   with  a  transmitter  power  output (TPO) in excess of the transmitter
   certificated rating. A station authorized under this subpart for a TPO that
   is less than its transmitter certificated rating shall determine its TPO in
   accordance with § 73.267 of this chapter and its TPO shall not be more than
   105 percent of the authorized TPO.

   (f) Composite antennas and antenna arrays may be used where the total ERP
   does not exceed the maximum determined in accordance with paragraphs (a),
   (b) or (c) of this section.

   (g) Either horizontal, vertical, circular or elliptical polarization may be
   used provided that the supplemental vertically polarized ERP required for
   circular  or elliptical polarization does not exceed the ERP otherwise
   authorized. Either clockwise or counterclockwise rotation may be used.
   Separate transmitting antennas are permitted if both horizontal and vertical
   polarization is to be provided.

   (h) All applications must comply with § 73.316, paragraphs (d) and (e) of
   this chapter.

   (i) An application that specifies use of a directional antenna must comply
   with § 73.316, paragraphs (c)(1) through (c)(3) of this chapter. Prior to
   issuance of a license, the applicant must: (1) Certify that the antenna is
   mounted in accordance with the specific instructions provided by the antenna
   manufacturer; and (2) certify that the antenna is mounted in the proper
   orientation. In instances where a directional antenna is proposed for the
   purpose of providing protection to another facility, a condition may be
   included in the construction permit requiring that before program tests are
   authorized,  a  permittee:  (1)  Must submit the results of a complete
   proof-of-performance to establish the horizontal plane radiation patterns
   for both the horizontally and vertically polarized radiation components;
   and,  (2) must certify that the relative field strength of neither the
   measured horizontally nor vertically polarized radiation component shall
   exceed at any azimuth the value indicated on the composite radiation pattern
   authorized by the construction permit.

   Note: Existing licensees and permittees that do not furnish data sufficient
   to calculate the contours in conformance with § 74.1204 will be assigned
   protected contours having the following radii:

   Up to 10 watts—1 mile (1.6 km) from transmitter site.

   Up to 100 watts—2 miles (3.2 km) from transmitter site.

   Up to 250 watts—4 miles (6.5 km) from transmitter site.

   (j) FM translator stations authorized prior to June 1, 1991, with facilities
   that do not comply with the ERP limitation of paragraph (a) or (b) of this
   section, as appropriate, may continue to operate, provided that operation is
   in conformance with § 74.1203 regarding interference. Applications for major
   changes in FM translator stations must specify facilities that comply with
   paragraph (a) or (b) of this section, as appropriate.

   [ 55 FR 50697 , Dec. 10, 1990, as amended at  56 FR 56170 , Nov. 1, 1991;  58 FR 42026 , Aug. 6, 1993;  62 FR 51063 , Sept. 30, 1997;  63 FR 33879 , June 22,
   1998;  63 FR 36605 , July 7, 1998]

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