§  1.924   Quiet zones.

   Areas implicated by this paragraph are those in which it is necessary
   to restrict radiation so as to minimize possible impact on the
   operations of radio astronomy or other facilities that are highly
   sensitive to interference. Consent throughout this paragraph means
   written consent from the quiet zone, radio astronomy, research, and
   receiving installation entity. The areas involved and procedures
   required are as follows:

   (a) NRAO, NRRO. The requirements of this paragraph are intended to
   minimize possible interference at the National Radio Astronomy
   Observatory site located at Green Bank, Pocahontas County, West
   Virginia, and at the Naval Radio Research Observatory site at Sugar
   Grove, Pendleton County, West Virginia.

   (1) Applicants and licensees planning to construct and operate a new or
   modified station at a permanent fixed location within the area bounded
   by N 39°15′0.4″ on the north, W 78°29′59.0″ on the east, N 37°30′0.4″
   on the south, and W 80°29′59.2″ on the west must notify the Director,
   National Radio Astronomy Observatory, Post Office Box No. 2, Green
   Bank, West Virginia 24944, in writing, of the technical details of the
   proposed operation. The notification must include the geographical
   coordinates of the antenna location, the antenna height, antenna
   directivity (if any), the channel, the emission type and power.

   (2) When an application for authority to operate a station is filed
   with the FCC, the notification required in paragraph (a)(1) of this
   section may be made prior to, or simultaneously with the application.
   The application must state the date that notification in accordance
   with paragraph (a)(1) of this section was made. After receipt of such
   applications, the FCC will allow a period of 20 days for comments or
   objections in response to the notifications indicated. If an applicant
   submits written consent from the National Radio Astronomy Observatory
   for itself or on behalf of the Naval Radio Research Observatory, the
   FCC will process the application without awaiting the conclusion of the
   20-day period. For services that do not require individual station
   authorization, entities that have obtained written consent from the
   National Radio Astronomy Observatory for itself or on behalf of the
   Naval Radio Research Observatory may begin to operate new or modified
   facilities prior to the end of the 20-day period. In instances in which
   notification has been made to the National Radio Astronomy Observatory
   prior to application filing, the applicant must also provide notice to
   the quiet zone entity upon actual filing of the application with the
   FCC. Such notice will be made simultaneous with the filing of the
   application and shall comply with the requirements of paragraph (a)(1)
   of this section.

   (3) If an objection is received during the 20-day period from the
   National Radio Astronomy Observatory for itself or on behalf of the
   Naval Radio Research Observatory, the FCC will, after consideration of
   the record, take whatever action is deemed appropriate.

   (b) Table Mountain. The requirements of this paragraph are intended to
   minimize possible interference at the Table Mountain Radio Receiving
   Zone of the Research Laboratories of the Department of Commerce located
   in Boulder County, Colorado.

   (1) Licensees and applicants planning to construct and operate a new or
   modified station at a permanent fixed location in the vicinity of
   Boulder County, Colorado are advised to give consideration, prior to
   filing applications, to the need to protect the Table Mountain Radio
   Receiving Zone from interference. To prevent degradation of the present
   ambient radio signal level at the site, the Department of Commerce
   seeks to ensure that the field strengths of any radiated signals
   (excluding reflected signals) received on this 1800 acre site (in the
   vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West
   Longitude) resulting from new assignments (other than mobile stations)
   or from the modification or relocation of existing facilities do not
   exceed the values given in the following table:

   Field Strength Limits for Table Mountain ^1
   Frequency range Field strength
   (mV/m) Power flux density
   (dBW/m ^2)
   Below 540 kHz 10 −65.8
   540 to 1600 kHz 20 −59.8
   1.6 to 470 MHz 10 −65.8
   470 to 890 MHz 30 −56.2
   890 MHz and above 1 −85.8

   ^1 Note: Equivalent values of power flux density are calculated
   assuming free space characteristic impedance of 376.7Ω (120πΩ).

   (2) Advance consultation is recommended, particularly for applicants
   that have no reliable data to indicate whether the field strength or
   power flux density figures in the above table would be exceeded by
   their proposed radio facilities. In general, coordination is
   recommended for:

   (i) Stations located within 2.4 kilometers (1.5 miles) of the Table
   Mountain Radio Receiving Zone;

   (ii) Stations located within 4.8 kilometers (3 miles) transmitting with
   50 watts or more effective radiated power (ERP) in the primary plane of
   polarization in the azimuthal direction of the Table Mountain Radio
   Receiving Zone;

   (iii) Stations located with 16 kilometers (10 miles) transmitting with
   1 kW or more ERP in the primary plane of polarization in the azimuthal
   direction of Table Mountain Radio Receiving Zone;

   (iv) Stations located within 80 kilometers (50 miles) transmitting with
   25 kW or more ERP in the primary plane of polarization in the azimuthal
   direction of Table Mountain Receiving Zone.

   (3) Applicants concerned are urged to communicate with the Radio
   Frequency Manager, Department of Commerce, 325 Broadway, Boulder, CO
   80305; Telephone: 303-497-4619, Fax: 303-497-6982, E-mail:
   frequencymanager@its.bldrdoc.gov, in advance of filing their
   applications with the Commission.

   (4) The FCC will not screen applications to determine whether advance
   consultation has taken place. However, such consultation may avoid the
   filing of objections from the Department of Commerce or institution of
   proceedings to modify the authorizations of stations that radiate
   signals with a field strength or power flux density at the site in
   excess of those specified herein.

   (c) Federal Communications Commission protected field offices. The
   requirements of this paragraph are intended to minimize possible
   interference to FCC monitoring activities.

   (1) Licensees and applicants planning to construct and operate a new or
   modified station at a permanent fixed location in the vicinity of an
   FCC protected field office are advised to give consideration, prior to
   filing applications, to the need to avoid interfering with the
   monitoring activities of that office. FCC protected field offices are
   listed in §  0.121 of this chapter.

   (2) Applications for stations (except mobile stations) that could
   produce on any channel a direct wave fundamental field strength of
   greater than 10 mV/m (−65.8 dBW/m2 power flux density assuming a free
   space characteristic impedance of 120π Ω) in the authorized bandwidth
   at the protected field office may be examined to determine the
   potential for interference with monitoring activities. After
   consideration of the effects of the predicted field strength of the
   proposed station, including the cumulative effects of the signal from
   the proposed station with other ambient radio field strength levels at
   the protected field office, the FCC may add a condition restricting
   radiation toward the protected field office to the station
   authorization.

   (3) In the event that the calculated field strength exceeds 10 mV/m at
   the protected field office site, or if there is any question whether
   field strength levels might exceed that level, advance consultation
   with the FCC to discuss possible measures to avoid interference to
   monitoring activities should be considered. Prospective applicants may
   communicate with: Chief, Enforcement Bureau, Federal Communications
   Commission, Washington, DC 20554.

   (4) Advance consultation is recommended for applicants that have no
   reliable data to indicate whether the field strength or power flux
   density figure indicated would be exceeded by their proposed radio
   facilities. In general, coordination is recommended for:

   (i) Stations located within 2.4 kilometers (1.5 miles) of the protected
   field office;

   (ii) Stations located within 4.8 kilometers (3 miles) with 50 watts or
   more average effective radiated power (ERP) in the primary plane of
   polarization in the azimuthal direction of the protected field offices.

   (iii) Stations located within 16 kilometers (10 miles) with 1 kw or
   more average ERP in the primary plane of polarization in the azimuthal
   direction of the protected field office;

   (iv) Stations located within 80 kilometers (50 miles) with 25 kw or
   more average ERP in the primary plane of polarization in the azimuthal
   direction of the protected field office;

   (v) Advance coordination for stations transmitting on channels above
   1000 MHz is recommended only if the proposed station is in the vicinity
   of a protected field office designated as a satellite monitoring
   facility in §  0.121 of this chapter.

   (vi) The FCC will not screen applications to determine whether advance
   consultation has taken place. However, such consultation may serve to
   avoid the need for later modification of the authorizations of stations
   that interfere with monitoring activities at protected field offices.

   (d) Notification to the Arecibo Observatory. The requirements in this
   section are intended to minimize possible interference at the Arecibo
   Observatory in Puerto Rico. Licensees must make reasonable efforts to
   protect the Observatory from interference. Licensees planning to
   construct and operate a new station at a permanent fixed location on
   the islands of Puerto Rico, Desecheo, Mona, Vieques or Culebra in
   services in which individual station licenses are issued by the FCC;
   planning to construct and operate a new station at a permanent fixed
   location on these islands that may cause interference to the operations
   of the Arecibo Observatory in services in which individual station
   licenses are not issued by the FCC; or planning a modification of any
   existing station at a permanent fixed location on these islands that
   would increase the likelihood of causing interference to the operations
   of the Arecibo Observatory must notify the Interference Office, Arecibo
   Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, in writing or
   electronically (e-mail address: prcz@naic.edu ), of the technical
   parameters of the planned operation. Carriers may wish to use the
   interference guidelines provided by Cornell University as guidance in
   designing facilities to avoid interference to the Observatory. The
   notification must include identification of the geographical
   coordinates of the antenna location (NAD-83 datum), the antenna height,
   antenna directivity (if any), proposed channel and FCC Rule Part, type
   of emission, and effective isotropic radiated power.

   (1) In the Amateur radio service:

   (i) The provisions of paragraph (d) of this section do not apply to
   repeaters that transmit on the 1.2 cm or shorter wavelength bands; and

   (ii) The coordination provision of paragraph (d) of this section does
   not apply to repeaters that are located 16 km or more from the Arecibo
   observatory.

   (2) In services in which individual station licenses are issued by the
   FCC, the notification required in paragraph (d) of this section may be
   made prior to, or simultaneously with, the filing of the application
   with the FCC, and at least 20 days in advance of the applicant's
   planned operation. The application must state the date that
   notification in accordance with paragraph (d) of this section was made.
   In services in which individual station licenses are not issued by the
   FCC, the notification required in paragraph (d) of this section should
   be sent at least 45 days in advance of the applicant's planned
   operation. In the latter services, the Interference Office must inform
   the FCC of a notification by an applicant within 20 days if the Office
   plans to file comments or objections to the notification. After the FCC
   receives an application from a service applicant or is informed by the
   Interference Office of a notification from a service applicant, the FCC
   will allow the Interference Office a period of 20 days for comments or
   objections in response to the application or notification. If an
   applicant submits written consent from the Interference Office, the FCC
   will process the application without awaiting the conclusion of the
   20-day period. For services that do not require individual station
   authorization, entities that have obtained written consent from the
   Interference Office may begin to operate new or modified facilities
   prior to the end of the 20-day period. In instances in which
   notification has been made to the Interference Office prior to
   application filing, the applicant must also provide notice to the
   Interference Office upon actual filing of the application with the FCC.
   Such notice will be made simultaneous with the filing of the
   application and shall comply with the requirements of paragraph (d) of
   this section.

   (3) If an objection to any planned service operation is received during
   the 20-day period from the Interference Office, the FCC will take
   whatever action is deemed appropriate.

   (4) The provisions of paragraph (d) of this section do not apply to
   operations that transmit on frequencies above 15 GHz.

   (e) Government satellite earth stations. (1) To minimize or avoid
   harmful interference to Government Satellite Earth Stations located in
   the Denver, Colorado and Washington, DC areas, any application for a
   new station license to operate in the 17.8-19.7 GHz band (except for
   low power operations governed by §  101.147(r)(10) of this chapter), or
   for modification of an existing station license in this band which
   would change the frequency, power, emission, modulation, polarization,
   antenna height or directivity, or location of such a station, must be
   coordinated with the Federal Government by the Commission before an
   authorization will be issued, if the station or proposed station is
   located in whole or in part within any of the areas defined by the
   following rectangles or circles:

Denver, CO Area

   Rectangle 1:

   41°30′00″ N. Lat. on the north

   103°10′00″ W. Long. on the east

   38°30′00″ N. Lat. on the south

   106°30′00″ W. Long. on the west

   Rectangle 2:

   38°30′00″ N. Lat. on the north

   105°00′00″ W. Long. on the east

   37°30′00″ N. Lat. on the south

   105°50′00″ W. Long. on the west

   Rectangle 3:

   40°08′00″ N. Lat. on the north

   107°00′00″ W. Long. on the east

   39°56′00″ N. Lat. on the south

   107°15′00″ W. Long. on the west

Washington, DC Area

   Rectangle

   38°40′00″ N. Lat. on the north

   78°50′00″ W. Long. on the east

   38°10′00″ N. Lat. on the south

   79°20′00″ W. Long. on the west; or

   (2) Within a radius of 178 km of 38°48′00″ N. Lat./76°52′00″ W. Long.

   (3) In addition, no application seeking authority to operate in the
   17.8-19.7 GHz band will be accepted for filing if the proposed station
   is located within 20 km (or within 55 km if the application is for an
   outdoor low power operation pursuant to §  101.147(r)(10) of this
   chapter) of the following coordinated:

   Denver, CO area: 39°43′00″ N. Lat./104°46′00″ W. Long.

   Washington, DC area: 38°48′00″ N. Lat./76°52′00″ W. Long.

   (4) In the band 17.7-17.8 GHz, fixed service applications, under parts
   74, 78, or 101 of this chapter, supporting Multichannel Video
   Programming Distributors shall be coordinated with the Federal
   Government by the Commission before an authorization will be issued if
   the station or proposed station is located in whole or in part within
   any of the areas defined in paragraphs (e)(1) or (e)(2) of this
   section.

   (f) 420-450 MHz band. (1) In the band 420-450 MHz, applicants should
   not expect to be accommodated if their area of service is within 160
   kilometers (100 miles) of the following locations:

   (i) 41°45′00.2″ N, 70°30′58.3″ W.,

   (ii) 64°17′00.0″ N., 149°10′00.0″ W.,

   Note to: Paragraph (f)(ii) is referenced to NAD27.

   (iii) 48°43′00.0″ N., 97°54′01.4″ W.;

   (2) Within 200 kilometers (124 miles) of the following locations:

   (i) 32°38′00.5″ N., 83°34′59.7″ W.,

   (ii) 31°25′00.6″ N., 100°24′01.3″ W.;

   (3) Within 240 kilometers (150 miles) of the following location:

   (i) 39°07′59.6″ N., 121°26′03.9″ W.;

   (ii) [Reserved]

   (4) Within 320 kilometers (200 miles) of the following locations:

   (i) 28°21′01.0″ N., 80°42′59.2″ W.,

   (ii) 30°30′00.7″ N., 86°29′59.8″ W.,

   (iii) 34°08′59.6″ N, 119°11′03.8″ W;

   (5) Or in the following locations:

   (i) The state of Arizona,

   (ii) The state of Florida,

   (iii) Portions of California and Nevada south of 37°10′ N.,

   (iv) And portions of Texas and New Mexico bounded by 31°45′ N., 34°30′
   N., 104°00′ W., and 107°30′ W.

   (g) GOES. The requirements of this paragraph are intended to minimize
   harmful interference to Geostationary Operational Environmental
   Satellite earth stations receiving in the band 1670-1675 MHz, which are
   located at Wallops Island, Virginia; Fairbanks, Alaska; and Greenbelt,
   Maryland.

   (1) Applicants and licensees planning to construct and operate a new or
   modified station within the area bounded by a circle with a radius of
   100 kilometers (62.1 miles) that is centered on 37°56′44″ N, 75°27′37″
   W (Wallops Island) or 64°58′22″ N, 147°30′04″ W (Fairbanks) or within
   the area bounded by a circle with a radius of 65 kilometers (40.4
   miles) that is centered on 39°00′02″ N, 76°50′29″ W (Greenbelt) must
   notify the National Oceanic and Atmospheric Administration (NOAA) of
   the proposed operation. For this purpose, NOAA maintains the GOES
   coordination Web page at http://www.osd.noaa.gov/radio/frequency.htm,
   which provides the technical parameters of the earth stations and the
   point-of-contact for the notification. The notification shall include
   the following information: Requested frequency, geographical
   coordinates of the antenna location, antenna height above mean sea
   level, antenna directivity, emission type, equivalent isotropically
   radiated power, antenna make and model, and transmitter make and model.

   (2) Protection. (i) Wallops Island and Fairbanks. Licensees are
   required to protect the Wallops Island and Fairbanks sites at all
   times.

   (ii) Greenbelt. Licensees are required to protect the Greenbelt site
   only when it is active. Licensees should coordinate appropriate
   procedures directly with NOAA for receiving notification of times when
   this site is active.

   (3) When an application for authority to operate a station is filed
   with the FCC, the notification required in paragraph (f)(1) of this
   section should be sent at the same time. The application must state the
   date that notification in accordance with paragraph (f)(1) of this
   section was made. After receipt of such an application, the FCC will
   allow a period of 20 days for comments or objections in response to the
   notification.

   (4) If an objection is received during the 20-day period from NOAA, the
   FCC will, after consideration of the record, take whatever action is
   deemed appropriate.

   Note to §  1.924: Unless otherwise noted, all coordinates cited in this
   section are specified in terms of the North American Datum of 1983 (NAD
   83).

   [ 63 FR 68924 , Dec. 14, 1998, as amended at  67 FR 6182 , Feb. 11, 2002;
    67 FR 13224 , Mar. 21, 2002;  67 FR 41852 , June 20, 2002;  67 FR 71111 ,
   Nov. 29, 2002;  69 FR 17957 , Apr. 6, 2004;  70 FR 31372 , June 1, 2005;  71 FR 69046 , Nov. 29, 2006;  73 FR 25420 , May 6, 2008;  75 FR 62932 , Oct.
   13, 2010]

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