{"data":{"id":"us/47-cfr-87.137","jurisdiction":"us","citation":"47 CFR 87.137","heading":"Types of emission.","body":"(a) The assignable emissions, corresponding emission designators and authorized bandwidths are as follows:\nClass of emission Emission designator Authorized bandwidth (kilohertz)\nBelow 50 MHz Above 50 MHz Frequency deviation\nA1A 1 100HA1A 0.25\nA1N 300HA1N 0.75\nA2A 2K04A2A 2.74 50\nA2D 6K0A2D 50\nA2D 5 13K0A2D 50\nA3E 2 6K00A3E 50 3\nA3E 5K6A3E 8.33 kHz 17\nA3X 4 3K20A3X 25\nA9W 5 13K0A9W 25\nF1B 1 1K70F1B 1.7\nF1B 1 2K40F1B 2.5\nF1D 18 1M30F1D 1300 kHz 312.5 kHz\nF2D 5M0F2D (9)\nF3E 6 16K0F3E 20 5\nF3E 7 36K0F3E 40 15\nF7D 8 5M0F7D 9\nF9D 5M0F9D 9\nG1D 16K0G1D 20 kHz\nG1D 16 21K0G1D 25\nG1D 14K0G1D 25\nF9D 5M0F9D 9\nG1D 16K0G1D 20 kHz\nG3E 6 16K0G3E 20 5\nG7D 14K0G7D 25\nH2B 10 11 2K80H2B 3.0\nH3E 11 12 2K80H3E 3.0\nJ2A 1 100HJ2A 0.25\nJ2B 1 1K70J2B 1.7\n2K40J2B 2.5\nJ3E 11 12 2K80J3E 3.0\nJ7B 11 2K80J7B 3.0\nJ7D 5M0J7D 9\nJ9W 11 2K80J9W 3.0\nM1A 620HM1A\nM1D 14M0M1D 14.0\nNON NON None 15\nPON 13 9 9\nR3E 11 12 2K80R3E 3.0\nXXA 14 1K12XXA 2.74\nNotes:\n1 A1A, F1B, J2A and J2B are permitted provided they do not cause harmful interference to H2B, J3E, J7B and J9W.\n2 For use with an authorized bandwidth of 8.0 kilohertz at radiobeacon stations. A3E will not be authorized:\n(i) At existing radiobeacon stations that are not authorized to use A3 and at new radiobeacon stations unless specifically recommended by the FAA for safety purposes.\n(ii) At existing radiobeacon stations currently authorized to use A3, subsequent to January 1, 1990, unless specifically recommended by the FAA for safety purposes.\n3 In the band 117.975-136 MHz, the authorized bandwidth is 25 kHz for transmitters approved after January 1, 1974.\n4 Applicable only to Survival Craft Stations and to the emergency locator transmitters and emergency locator transmitter test stations employing modulation in accordance with that specified in § 87.141 of the Rules. The specified bandwidth and modulation requirements shall apply to emergency locator transmitters for which approval is granted after October 21, 1973.\n5 This emission may be authorized for audio frequency shift keying and phase shift keying for digital data links on any frequency listed in § 87.263(a)(1), § 87.263(a)(3) or § 87.263(a)(5). 13K0A2D emission may be authorized on frequencies not used for voice communications. If the channel is used for voice communications, 13K0A9W emission may be authorized, provided the data is multiplexed on the voice carrier without derogating voice communications.\n6 Applicable to operational fixed stations in the bands 72.0-73.0 MHz and 75.4-76.0 MHz and to CAP stations using F3 on 143.900 MHz and 148.150 MHz.\n7 Applicable to operational fixed stations presently authorized in the band 73.0-74.6 MHz.\n8 The authorized bandwidth is equal to the necessary bandwidth for frequency or digitally modulated transmitters used in aeronautical telemetering and associated aeronautical telemetry or telecommand stations that operate in the 1435-1525 MHz, 2345-2395 MHz, or 5091-5150 MHz band. The necessary bandwidth must be computed in accordance with part 2 of this chapter.\n9 To be specified on license.\n10 H2B must be used by stations employing digital selective calling.\n11 For A1A, F1B and single sideband emissions, except H2B, the assigned frequency must be 1400 Hz above the carrier frequency.\n12 R3E, H3E, and J3E will be authorized only below 25000 kHz. Only H2B, J3E, J7B, and J9W are authorized, except that A3E and H3E may be used only on 3023 kHz and 5680 kHz for search and rescue operations.\n13 The letters “K, L, M, Q, V, W, and X” may also be used in place of the letter “P” for pulsed radars.\n14 Authorized for use at radiobeacon stations.\n15 Applicable only to transmitters of survival craft stations, emergency locator transmitter stations and emergency locator transmitter test stations approved after October 21, 1973.\n16 Authorized for use by aircraft earth stations. Lower values of necessary and authorized bandwidth are permitted.\n17 In the band 117.975-137 MHz, the Commission will not authorize any 8.33 kHz channel spaced transmissions or the use of their associated emission designator within the U.S. National Airspace System, except, on an optional basis, by Aeronautical Enroute Stations and Flight Test Stations, or by avionics equipment manufacturers which are required to perform installation and checkout of such radio systems prior to delivery to their customers. For transmitters certificated to tune to 8.33 kHz channel spacing as well as 25 kHz channel spacing, the authorized bandwidth is 8.33 kHz when tuned to an 8.33 kHz channel.\n18 Authorized only for Universal Access Transceiver use at 978 MHz.\n(b) For other emissions, an applicant must determine the emission designator by using part 2 of this chapter.\n(c) A license to use radiotelephony includes the use of tone signals or signaling devices whose sole function is to establish or maintain voice communications.","path":["Title 47—Telecommunication","CHAPTER I—FEDERAL COMMUNICATIONS COMMISSION","SUBCHAPTER D—SAFETY AND SPECIAL RADIO SERVICES","PART 87—AVIATION SERVICES","Subpart D—Technical Requirements"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-47.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:28Z","sha256":"17f19df73d041af14024a0e0f565f4ebab13637dacf4a9beae7531f1751c32be","source_id":"us-cfr","stale":true,"prev":"us/47-cfr-87.135","next":"us/47-cfr-87.139"},"notice":"GroundRules: Original legal text. Not legal advice."}