Sec.  2.102   Assignment of frequencies.

   (a) Except as otherwise provided in this section, the assignment of
   frequencies and bands of frequencies to all stations and classes of stations
   and the licensing and authorizing of the use of all such frequencies between
   9 kHz and 275 GHz, and the actual use of such frequencies for
   radiocommunication or for any other purpose, including the transfer of
   energy by radio, shall be in accordance with the Table of Frequency
   Allocations in  Sec. 2.106.

   (b) On the condition that harmful interference will not be caused to
   services operating in accordance with the Table of Frequency Allocations the
   following exceptions to paragraph (a) of this section may be authorized:

   (1) In individual cases the Commission may, without rule making proceedings,
   authorize on a temporary basis only, the use of frequencies not in
   accordance with the Table of Frequency Allocations for projects of short
   duration or emergencies where the Commission finds that important or
   exceptional circumstances require such utilization. Such authorizations are
   not intended to develop a service to be operated on frequencies other than
   those allocated such service.

   (2) A station for the development of techniques or equipment to be employed
   by services set forth in column 5 of the Table of Frequency Allocations may
   be authorized the use of frequencies allocated to those services or classes
   of stations.

   (3) Experimental stations, pursuant to part 5 of this chapter, may be
   authorized the use of any frequency or frequency band not exclusively
   allocated to the passive services (including the radio astronomy service).

   (4) In the event a band is reallocated so as to delete its availability for
   use by a particular service, the Commission may provide for the further
   interim use of the band by stations in that service for a temporary,
   specific period of time.

   (c) Non-Federal stations may be authorized to use Federal frequencies in the
   bands above 25 MHz if the Commission finds, after consultations with the
   appropriate Federal agency or agencies, that such use is necessary for
   coordination of Federal and non-Federal activities: Provided, however, that:

   (1) Non-Federal operation on Federal frequencies shall conform with the
   conditions agreed upon by the Commission and NTIA (the more important of
   which are contained in paragraphs (c)(2), (c)(3), and (c)(4) of this
   section);

   (2) Such operations shall be in accordance with NTIA rules governing the
   service to which the frequencies involved are allocated;

   (3) Such operations shall not cause harmful interference to Federal stations
   and, should harmful interference result, that the interfering non-Federal
   operation shall immediately terminate; and

   (4) Non-Federal operation has been certified as necessary by the Federal
   agency involved and this certification has been furnished, in writing, to
   the non-Federal licensee with which communication is required.

   (d) Aircraft stations may communicate with stations of the maritime mobile
   service. They shall then conform to those provisions of the international
   Radio Regulations which relate to the maritime mobile service. For this
   purpose aircraft stations should use the frequencies allocated to the
   maritime mobile service. However, having regard to interference which may be
   caused by aircraft stations at high altitudes, maritime mobile frequencies
   in the bands above 30 MHz shall not be used by aircraft stations in any
   specific area without the prior agreement of all administrations of the area
   in which interference is likely to be caused. In particular, aircraft
   stations operating in Region 1 should not use frequencies in the bands above
   30 MHz allocated to the maritime mobile service by virtue of any agreement
   between administrations in that Region.

   (e) Non-Federal services operating on frequencies in the band 25–50 MHz must
   recognize that it is shared with various services of other countries; that
   harmful interference may be caused by skywave signals received from distant
   stations of all services of the United States and other countries radiating
   power on frequencies in this band; and that no protection from such harmful
   interference generally can be expected. Persons desiring to avoid such
   harmful interference should consider operation on available frequencies
   higher in the radio spectrum not generally subject to this type of
   difficulty.

   (f) The stations of a service shall use frequencies so separated from the
   limits of a band allocated to that service as not to cause harmful
   interference to allocated services in immediately adjoining frequency bands.

   (g) In the bands above 25 MHz which are allocated to the non-Federal land
   mobile service, fixed stations may be authorized on the following
   conditions:

   (1) That such stations are authorized in the service shown in Column 5 of
   the Table of Frequency Allocations in the band in question;

   (2) That harmful interference will not be caused to services operating in
   accordance with the Table of Frequency Allocations.

   (h) Special provisions regarding the use of spectrum allocated to the fixed
   and land mobile services below 25 MHz by non-Federal stations.

   (1) Only in the following circumstances will authority be extended to
   stations in the fixed service to operate on frequencies below 25 MHz.

   (i) With respect to aeronautical fixed stations, only when a showing can be
   made that more suitable facilities are not available.

   (ii) With respect to fixed stations, except aeronautical fixed stations,
   only to:

   (A) Provide communication circuits in emergency and/or disaster situations,
   where safety of life and property are concerned;

   (B) Provide standby and/or backup facilities to satellite and cable circuits
   used for international public correspondence;

   (C) Provide standby and/or backup communications circuits to regular
   domestic communication circuits which have been disrupted by disasters
   and/or emergencies;

   (D) Provide communication circuits wholly within the State of Alaska and the
   United States insular areas in the Pacific; and

   (E) Provide communication circuits to support operations which are highly
   important to the national interest and where other means of
   telecommunication are unavailable.

   (2) Only in the following circumstances will authority be extended to
   stations in the land mobile service to operate below 25 MHz.

   (i) Provide communication circuits in emergency and/or disaster situations,
   where safety of life and property are concerned;

   (ii) Provide standby and/or backup communications circuits to regular
   domestic communication circuits which have been disrupted by disasters
   and/or emergencies;

   (iii) Provide communication circuits wholly within the State of Alaska and
   the United States insular areas in the Pacific; and

   (iv) Provide communication circuits to support operations which are highly
   important to the national interest and where other means of
   telecommunication are unavailable.

   (3) Except in the State of Alaska and the United States Pacific insular
   areas, the Commission does not intend to seek international protection for
   assignments made pursuant to paragraphs (h) (1)(ii) and (2) of this section;
   this results in the following constraints upon the circuits/assignments.

   (i) The Commission will not accept responsibility for protection of the
   circuits from harmful interference caused by foreign operations.

   (ii) In the event that a complaint of harmful interference resulting from
   operation of these circuits is received from a foreign source, the offending
   circuit(s) must cease operation on the particular frequency concerned.

   (iii) In order to accommodate the situations described in paragraphs (h)(3)
   (i) and (ii) of this section, equipments shall be capable of transmitting
   and receiving on any frequency in the bands assigned to the particular
   operation and capable of immediate change among the frequencies.

   [ 49 FR 2373 , Jan. 19, 1984,  70 FR 46585 , Aug. 10, 2005]