600-meter amateur radio band

The 600 meter (or 630 meter) amateur radio band is a frequency band allocated by the International Telecommunication Union (ITU) to amateur radio operators, and it ranges from 472 to 479 kHz, or equivalently 625.9 to 635.1 meters wavelength. It was formally allocated to amateurs at the 2012 World Radiocommunication Conference (WRC-12). The band is available on a secondary basis in all ITU regions with the limitation that amateur stations have maximum radiated power of 1 Watt effective isotropic radiated power (EIRP); however, stations more than 800 km from certain countries may be permitted to use 5 Watts EIRP.

The new WRC-12 allocation did not take formal effect until 1 January 2013. However, several countries previously allocated the WRC-12 band to amateurs domestically. Previously, several other countries have authorized temporary allocations or experimental operations on nearby frequencies.

The band is in the Medium Frequency (MF) region, within the greater 415–526.5 kHz maritime band.

With maritime traffic largely displaced from 500 kHz band, some countries had taken steps prior to 2012 to allocate frequencies at or near 500 kHz to amateur radio use.

During the 2012 World Radiocommunication Conference (WRC-12) of the International Telecommunication Union, a 15 kHz allocation to the amateur radio service was considered on a secondary use basis. The frequencies studied were between 415 kHz and 526.5 kHz. The result was that 472–479 kHz was identified as agreeable for all three ITU Regions, except for some countries such as Russia, China and Arab states. WRC-12 re-allocated the original 500 kHz frequency back to exclusive maritime mobile use for new navigation systems. On 14 February 2012, the delegates at WRC-12 formally approved allocating 472–479 kHz to the amateur radio service; however, this new allocation will not take effect until it is entered into the ITU's Radio Regulations. Following that, individual regulatory authorities need to implement the change nationally in order to make the allocation available to radio amateurs under their jurisdiction.

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