47 CFR § 73.28 - Assignment of stations to channels.
(a) The Commission will not make an AM station assignment that does not conform with international requirements and restrictions on spectrum use that the United States has accepted as a signatory to treaties, conventions, and other international agreements. See § 73.1650 for a list of pertinent treaties, conventions and agreements, and § 73.23 for procedural provisions relating to compliance with them.
(b) Engineering standards now in force domestically differ in some respects from those specified for international purposes. The engineering standards specified for international purposes (see § 73.1650, International Agreements) will be used to determine:
(1) The extent to which interference might be caused by a proposed station in the United States to a station in another country; and
(2) whether the United States should register an objection to any new or changed assignment notified by another country. The domestic standards in effect in the United States will be used to determine the extent to which interference exists or would exist from a foreign station where the value of such interference enters into a calculation of:
(i) The service to be rendered by a proposed operation in the United States; or
(ii) the permissible interfering signal from one station in the United States to another United States station.