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Source: http://www.iaru.org/ac-spec.html The International Amateur Radio Union IARU Administrative Council, Revised March 1999 Spectrum Requirements of the Amateur and Amateur-Satellite Services
Where possible, country footnotes for additional
or alternative allocations in bands that are listed in the international Table
of Frequency Allocations as Amateur or Amateur-Satellite allocations, should be
deleted. Efforts to add the names of countries to such footnotes should be
opposed.
The Amateur Service seeks a shared LF allocation. At the present time, there is no global or regional allocation to the Amateur Service in the low-frequency (LF) band. This frequency range has characteristics quite unlike those of higher frequencies, and there is considerable interest in LF propagation and antenna experimentation by individuals. IARU Region 1 (Tel-Aviv, 1996) recommends that member societies in Region 1 seek access to a segment, preferably in the vicinity of 136 kHz, on a secondary, non-interference basis. Coordinated efforts by IARU Region 1 have led to the adoption by the CEPT European Radiocommunications Committee of Recommendation 62-01, that the band 135.7 - 137.8 kHz may be used with a maximum ERP of 1 watt on a secondary basis by the Amateur Service in the 42 CEPT countries. This recommendation came into force in May 1997 and has already been implemented by several CEPT countries, either with the specified ERP limit or with a transmitter power limit of 100 watts. It could serve as the basis for an allocation in other geographical areas. In May 1996, through RSGB efforts, amateurs in the UK obtained access to the band 71.6-74.4 kHz with up to 1 watt ERP. In the year 2000 this allocation will be phased out. The CEPT recommended allocation became available to UK amateurs in January 1998. Some administrations issue experimental licenses to amateurs or otherwise permit LF low-power operation; for example, in the band 160-190 kHz in the USA and 165-190 kHz in Australia and New Zealand. In a spectrum study, the USA administration approved, in principle, an ARRL requirement for a shared allocation in the vicinity of 160--190 kHz. Subsequently, the ARRL decided to petition the FCC for domestic allocations in the bands 135.7--137.8 kHz and 160--190 kHz. Although a worldwide harmonized allocation at LF
would facilitate propagation experimentation and antenna design, it may be
necessary to accept regional allocations in order to be compatible with existing
users, including broadcasting.
In the vicinity of 1800 kHz, the Amateur Service requires an exclusive worldwide allocation of 100 kHz and an additional shared worldwide allocation of 100 kHz. This band presently is the lowest-frequency amateur allocation, and is the only medium-frequency (MF) allocation to the Amateur Service. Its propagation characteristics allow short range communications during the daytime hours and medium and long range communications during the night-time hours. This band is particularly useful during sunspot minima, when the maximum usable frequency (MUF) is below 3500 kHz. There is reason to believe that the growing use of GNSS (GPS and GLONASS) positioning systems will render obsolete radiolocation systems operating in the band 1900-2000 kHz. |
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