10 meters

The 10-meter band is a portion of the shortwave radio spectrum internationally allocated to amateur radio and amateur satellite use on a primary basis. The band consists of frequencies stretching from 28.000 to 29.700 MHz.

The 10-meter band was allocated on a worldwide basis by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927. Its frequency allocation was then 28000-30000 kc.

A 300 kHz segment, from 29.700 MHz to 30.000 MHz, was removed from the amateur radio allocation by the 1947 International Radio Conference of Atlantic City.

In the late 1970s, the impending ban by the FCC of the sale of older 23-channel CB equipment that did not meet more stringent restrictions on newer, 40-channel units, meant that a surplus of 23-channel CB gear was on the market. This was a windfall for amateur radio enthusiasts, allowing access to fairly inexpensive radios which could easily be modified for use in the 10-meter band.

American Novice- and Technician-class licensees were granted CW and SSB segments on the 10-meter band as of 0001 UTC March 21, 1987.

With the elimination of Morse code testing requirements for U.S. amateurs in February 2007, Technician-class licensees who have not passed a code test may operate with up to 200 watts PEP using CW and SSB modes in a portion of the 10-meter band.

Being a very wide band in HF terms, many different transmission modes can be found on 10 meters. Morse code and other narrowband modes are found toward the bottom portion of the band, SSB from 28.300 MHz up, and wideband modes (AM and FM) are found near the upper part of the bottom portion of the band. Digital modes, such as PSK-31, are also allowed in the upper portion of the band, with 28.120 being a popular PSK-31 frequency.

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