40-meter band

The 40-meter or 7-MHz band is an amateur radio frequency band, spanning 7000-7300 kHz in ITU Region-2, and 7000-7200 kHz in Regions 1 & 3. It is allocated to radio amateurs worldwide on a primary basis; however, only 7000-7100 kHz is exclusively allocated to amateur radio worldwide. Shortwave broadcasters and land mobile users also have primary allocations in some countries, and amateur stations must share the band with these users.

40 meters is considered one of the most reliable all-season long distance communication (DX) bands.

The 40-meter band was made available to amateurs in the United States by the Third National Radio Conference on October 10, 1924, and allocated on a worldwide basis by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927.

For many years the portion of the band from 7100–7300 kHz has been allocated to short wave broadcasters outside the Americas, and not available to radio amateurs outside of ITU Region 2. At the World Radio Conference WRC-03 in 2003 it was agreed that the broadcast stations would move out of the section 7100–7200 kHz on 29 March 2009 and that portion would become a worldwide exclusive amateur allocation afterwards. Releasing the remaining 100 kHz of the band to amateurs at a later date is an IARU aim for future conferences.

This band supports both long distance (DX) communications between late afternoon and a few hours after sunrise, and short distance NVIS contacts during most daylight hours.

With its unique combination of intra- and intercontinental communications possibilities, 40 meters is considered a key band in building a winning HF contesting score during any part of the sunspot cycle.

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