§  73.807   Minimum distance separation between stations.

   Minimum separation requirements for LP100 and LP10 stations, as defined
   in § §  73.811 and 73.853, are listed in the following paragraphs. An
   LPFM station will not be authorized unless the co-channel, first- and
   second-adjacent and IF channel separations are met. An LPFM station
   need not satisfy the third-adjacent channel separations listed in
   paragraphs (a) through (d) in order to be authorized. Minimum distances
   for co-channel and first-adjacent channel are separated into two
   columns. The left-hand column lists the required minimum separation to
   protect other stations and the right-hand column lists (for
   informational purposes only) the minimum distance necessary for the
   LPFM station to receive no interference from other stations assumed to
   be operating at the maximum permitted facilities for the station class.
   For second-adjacent channel and I.F. channels, the required minimum
   distance separation is sufficient to avoid interference received from
   other stations.

   (a)(1) An LP100 station will not be authorized initially unless the
   minimum distance separations in the following table are met with
   respect to authorized FM stations, applications for new and existing FM
   stations filed prior to the release of the public notice announcing an
   LPFM window period for LP100 stations, authorized LP100 stations, LP100
   station applications that were timely-filed within a previous window,
   and vacant FM allotments. LP100 stations are not required to protect
   LP10 stations. LPFM modification applications must either meet the
   distance separations in the following table or, if short-spaced, not
   lessen the spacing to subsequently authorized stations.
   Station class protected by LP100 Co-channel minimum
   separation (km) First-adjacent channel
   minimum separation (km) Second- and third-adjacent channel minimum
   separation (km) I.F. channel minimum separations
   Required For no interference received from max. class facility Required
   For no interference received from max. class facility Required 10.6 or
   10.8 MHz
   LP100 24 24 14 14 None None
   D 24 24 13 13 6 3
   A 67 92 56 56 29 6
   B1 87 119 74 74 46 9
   B 112 143 97 97 67 12
   C3 78 119 67 67 40 9
   C2 91 143 80 84 53 12
   C1 111 178 100 111 73 20
   C0 122 193 111 130 84 22
   C 130 203 120 142 93 28

   (2) LP100 stations must satisfy the second-adjacent channel minimum
   distance separation requirements of paragraph (a)(1) of this section
   with respect to any third-adjacent channel FM station that, as of
   September 20, 2000 (the adoption date of this MO&O ) broadcasts a radio
   reading service via a subcarrier frequency.

   (b)(1) An LP10 station will not be authorized unless the minimum
   distance separations in the following table are met with respect to
   authorized FM stations, applications for new and existing FM stations
   filed prior to the release of the public notice announcing an LPFM
   window period for LP10 stations, vacant FM allotments, or LPFM
   stations.
   Station class protected by LP10 Co-channel minimum
   separation (km) First-adjacent channel
   minimum separation
   (km) Second- and third-adjacent channel minimum separation (km) I.F.
   Channel minimum separations
   Required For no interference received from max. class facility Required
   For no interference received from max. class facility Required 10.6 or
   10.8 MHz
   LP100 16 22 10 11 None None
   LP10 13 13 8 8 None None
   D 16 21 10 11 6 2
   A 59 90 53 53 29 5
   B1 77 117 70 70 45 8
   B 99 141 91 91 66 11
   C3 69 117 64 64 39 8
   C2 82 141 77 81 52 11
   C1 103 175 97 108 73 18
   C0 114 190 99 127 84 21
   C 122 201 116 140 92 26

   (2) LP10 stations must satisfy the second-adjacent channel minimum
   distance separation requirements of paragraph (b)(1) of this section
   with respect to any third-adjacent channel FM station that, as of
   September 20, 2000 (the adoption date of this MO&O ) broadcasts a radio
   reading service via a subcarrier frequency.

   (c) In addition to meeting or exceeding the minimum separations for
   Class LP100 and Class LP10 stations in paragraphs (a) and (b) of this
   section, new LP100 and LP10 stations will not be authorized in Puerto
   Rico or the Virgin Islands unless the minimum distance separations in
   the following tables are met with respect to authorized or proposed FM
   stations:

   (1) LP100 stations in Puerto Rico and the Virgin Islands:
   Station class protected by LP100 Co-channel minimum
   separation (km) First-adjacent channel
   minimum separation (km) Second- and third-adjacent channel minimum
   separation (km)—required I.F. channel minimum separations—10.6 or 10.8
   MHz
   Required For no interference received from max. class facility Required
   For no interference received from max. class facility
   A 80 111 70 70 42 9
   B1 95 128 82 82 53 11
   B 138 179 123 123 92 19

   (2) LP10 stations in Puerto Rico and the Virgin Islands:
   Station class protected by LP100 Co-channel minimum
   separation (km) First-adjacent channel
   minimum separation (km) Second- and third-adjacent channel minimum
   separation (km)—required I.F. channel minimum separations—10.6 or 10.8
   MHz
   Required For no interference received from max. class facility Required
   For no interference received from max. class facility
   A 72 108 66 66 42 8
   B1 84 125 78 78 53 9
   B 126 177 118 118 92 18

   Note to paragraphs ( a ), ( b ), and ( c ): Minimum distance
   separations towards “grandfathered” superpowered Reserved Band stations
   are as specified.

   Full service FM stations operating within the reserved band (Channels
   201-220) with facilities in excess of those permitted in §  73.211(b)(1)
   or §  73.211(b)(3) shall be protected by LPFM stations in accordance
   with the minimum distance separations for the nearest class as
   determined under §  73.211. For example, a Class B1 station operating
   with facilities that result in a 60 dBu contour that exceeds 39
   kilometers but is less than 52 kilometers would be protected by the
   Class B minimum distance separations. Class D stations with 60 dBu
   contours that exceed 5 kilometers will be protected by the Class A
   minimum distance separations. Class B stations with 60 dBu contours
   that exceed 52 kilometers will be protected as Class C1 or Class C
   stations depending upon the distance to the 60 dBu contour. No stations
   will be protected beyond Class C separations.

   (d) In addition to meeting the separations (a) through (c), LPFM
   applications must meet the minimum separation requirements with respect
   to authorized FM translator stations, cutoff FM translator
   applications, and FM translator applications filed prior to the release
   of the Public Notice announcing the LPFM window period:

   (1) LP100 stations:
   Distance to FM translator 60 dBu contour Co-channel minimum separation
   (km) First-adjacent channel minimum
   separation (km) Second- and third-adjacent channel minimum
   separation (km)
   required I.F . Channel minimum
   separation (km)
   10.6 or 10.8 MHz
   Required For no
   interference
   received Required For no
   interference
   received
   13.3 km or greater 39 67 28 35 21 5
   Greater than 7.3 km, but less than 13.3 km 32 51 21 26 14 5
   7.3 km or less 26 30 15 16 8 5

   (2) LP10 Stations:
   Distance to FM translator 60 dBu contour Co-channel minimum separation
   (km) First-adjacent channel minimum
   separation (km) Second- and third-adjacent channel minimum
   separation (km)
   required I.F . Channel minimum
   separation (km)
   10.6 or 10.8 MHz
   Required For no
   interference
   received Required For no
   interference
   received
   13.3 km or greater 30 65 25 33 20 3
   Greater than 7.3 km, but less than 13.3 km 24 49 18 23 14 3
   7.3 km or less 18 28 12 14 8 3

   (e) Existing Class LP100 and LP10 stations which do not meet the
   separations in paragraphs (a) through (e) of this section may be
   relocated provided that the separation to any short-spaced station is
   not reduced.

   (f) Commercial and noncommercial educational stations authorized under
   subparts B and C of this part, as well as new or modified commercial FM
   allotments, are not required to adhere to the separations specified in
   this rule section, even where new or increased interference would be
   created.

   (g) International considerations within the border zones. (1) Within
   320 km of the Canadian border, LP100 stations must meet the following
   minimum separations with respect to any Canadian stations:
   Canadian station class Co-channel (km) First-adjacent channel (km)
   Second-adjacent channel (km) Third-adjacent channel (km) Intermediate
   frequency (IF) channel (km)
   A1 & Low Power 45 30 21 20 4
   A 66 50 41 40 7
   B1 78 62 53 52 9
   B 92 76 68 66 12
   C1 113 98 89 88 19
   C 124 108 99 98 28

   (2) Within 320 km of the Mexican border, LP100 stations must meet the
   following separations with respect to any Mexican stations:
   Mexican station class Co-channel (km) First-adjacent channel (km)
   Second-third adjacent channel (km) Intermediate frequency (IF) channel
   (km)
   Low Power 27 17 9 3
   A 43 32 25 5
   AA 47 36 29 6
   B1 67 54 45 8
   B 91 76 66 11
   C1 91 80 73 19
   C 110 100 92 27

   (3) Within 320 km of the Canadian border, LP10 stations must meet the
   following minimum separations with respect to any Canadian stations:
   Canadian station class Co-channel (km) First-adjacent channel (km)
   Second-adjacent channel (km) Third-adjacent channel (km) Intermediate
   frequency (IF) channel (km)
   A1 & Low Power 33 25 20 19 3
   A 53 45 40 39 5
   B1 65 57 52 51 8
   B 79 71 67 66 11
   C1 101 93 88 87 18
   C 111 103 98 97 26

   (4) Within 320 km of the Mexican border, LP10 stations must meet the
   following separations with respect to any Mexican stations:
   Mexican station class Co-channel (km) First-adjacent channel (km)
   Second-third adjacent channel (km) Intermediate frequency (IF) channel
   (km)
   Low Power 19 13 9 2
   A 34 29 24 5
   AA 39 33 29 5
   B1 57 50 45 8
   B 79 71 66 11
   C1 83 77 73 18
   C 102 96 92 26

   (5) The Commission will notify the International Telecommunications
   Union (ITU) of any LPFM authorizations in the US Virgin Islands. Any
   authorization issued for a US Virgin Islands LPFM station will include
   a condition that permits the Commission to modify, suspend or terminate
   without right to a hearing if found by the Commission to be necessary
   to conform to any international regulations or agreements.

   (6) The Commission will initiate international coordination of a LPFM
   proposal even where the above Canadian and Mexican spacing tables are
   met, if it appears that such coordination is necessary to maintain
   compliance with international agreements.

   [ 65 FR 7640 , Feb. 15, 2000, as amended at  65 FR 67299 , Nov. 9, 2000;  65 FR 79779 , Dec. 20, 2000;  66 FR 23863 , May 10, 2001;  77 FR 20558 , Apr.
   5, 2012]

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