U.S. Non-Federal-Government Allocations
435 - 495 kHz

U.S. Federal Government Allocations
435 - 495 kHz
Aeronautical radionavigation

ITU Region 1 Allocations
479 - 495 kHz
Aeronautical radionavigation 5.77

ITU Region 2 Allocations
479 - 495 kHz
Aeronautical radionavigation 5.77 5.80

ITU Region 3 Allocations
479 - 495 kHz
Aeronautical radionavigation 5.77 5.80



5.77 Different category of service: in Australia, China, the French overseas communities of Region 3, India, Iran (Islamic Republic of), Japan, Pakistan, Papua New Guinea and Sri Lanka, the allocation of the band 415-495 kHz to the aeronautical radionavigation service is on a primary basis. Administrations in these countries shall take all practical steps necessary to ensure that aeronautical radionavigation stations in the band 435-495 kHz do not cause interference to reception by coast stations of ship stations transmitting on frequencies designated for ship stations on a worldwide basis (see No. 52.39). (WRC-07)

5.79 The use of the bands 415-495 kHz and 505-526.5 kHz (505-510 kHz in Region 2) by the maritime mobile service is limited to radiotelegraphy.

5.79A When establishing coast stations in the NAVTEX service on the frequencies 490 kHz, 518 kHz and 4209.5 kHz, administrations are strongly recommended to coordinate the operating characteristics in accordance with the procedures of the International Maritime Organization (IMO) (see Resolution 339 (Rev.WRC-07)).

5.80 In Region 2, the use of the band 435-495 kHz by the aeronautical radionavigation service is limited to non-directional beacons not employing voice transmission.

5.82 In the maritime mobile service, the frequency 490 kHz is to be used exclusively for the transmission by coast stations of navigational and meteorological warnings and urgent information to ships, by means of narrow-band direct-printing telegraphy. The conditions for use of the frequency 490 kHz are prescribed in Articles 31 and 52. In using the band 415-495 kHz for the aeronautical radionavigation service, administrations are requested to ensure that no harmful interference is caused to the frequency 490 kHz. (WRC-07)

US2 In the band 9-490 kHz, electric utilities operate Power Line Carrier (PLC) systems on power transmission lines for communications important to the reliability and security of electric service to the public. These PLC systems operate under the provisions of 47 CFR part 15, or Chapter 8 of the NTIA Manual, on an unprotected and non-interference basis with respect to authorized radio users. Notification of intent to place new or revised radio frequency assignments or PLC frequency uses in the band 9-490 kHz is to be made in accordance with the Rules and Regulations of the FCC and NTIA, and users are urged to minimize potential interference to the extent practicable. This footnote does not provide any allocation status to PLC radio frequency uses.

US231 When an assignment cannot be obtained in the bands between 200 kHz and 525 kHz, which are allocated to aeronautical radionavigation, assignments may be made to aeronautical radiobeacons in the maritime mobile band 435-490 kHz, on a secondary basis, subject to the coordination and agreement of those agencies having assignments within the maritime mobile band which may be affected. Assignments to Federal aeronautical radionavigation radiobeacons in the band 435-490 kHz shall not be a bar to any required changes to the maritime mobile radio service and shall be limited to non-voice emissions.


Amateur Radio Secondary Allocation Adopted at WRC-12
Avalanche transceivers
Amateur Radio 630-meter Band

Related Documents, Links, and Multimedia:
FCC Proceeding (2)

Engineering Data

Lower Frequency Center Frequency Upper Frequency
Frequency 435 kHz 465 kHz 495 kHz
Wavelength 689.2 m 644.7 m 605.6 m
Band designator(s) MF MF MF
Isotropic collecting area 37,796.6 m2 33,077.0 m2 29,189.1 m2
Free space loss (1 m) N/A (near field) N/A (near field) N/A (near field)
Free space loss (1 km) 26.1 dB 25.8 dB 26.3 dB
Free space loss (10 km) 46.1 dB 45.8 dB 46.3 dB
Free space loss (100 km) 66.1 dB 65.8 dB 66.3 dB
Free space loss (1000 km) 86.1 dB 85.8 dB 86.3 dB
Free space loss
(35,786 km = GEO orbit)
117.1 dB 116.9 dB 117.4 dB
Free space loss (378,370 km = Moon) 137.6 dB 137.4 dB 137.9 dB