10-meter band

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

History

The 10-meter band was created by the [http://www.twiar.org/aaarchives/WB008.txt Washington International Radiotelegraph Conference] on November 25, 1927.

A 300 kHz segment, from 29.700 MHz to 30.000 MHz, was removed from the amateur radio allocation in 1947.Fact|date=May 2008

OSCAR-5, built at the University of Melbourne, Australia, and launched in 1970 on a NASA flight, was the first OSCAR to transmit on the 10-meter band.Fact|date=May 2008

In the late 1970s, with 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 on March 20, 1987.Fact|date=May 2008

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.

Operating

Being a very wide band in HF terms, many different transmission modes can be found on 10 meters. Morse Code and other Narrowband modes found toward the bottom portion of the band, Single-sideband modulation (SSB) from 28.300 MHz and above, Wideband modes such as Amplitude Modulation (AM) and Frequency Modulation (FM) are found near the top portion of the band.

Propagation characteristics

*Radio propagationDue to its unique spot in the spectrum, 10 meters can be fascinating, if not occasionally challenging, to work. At peak times of the solar cycle when many sunspots appear on the Sun's surface, 10 meters can be alive with extremely long-distance signals, refracting from the F2 layer in the ionosphere. Primarily a daytime band, 10 meters will come alive during high solar periods soon after sunrise, and often remain "open" until several hours after sunset.

Long distance opportunities via F2 seem to follow the Sun across the globe. In North America, for instance, F2 might bring Europe and Western Asia in the morning, The Americas during midday, and the Pacific and East Asia in late afternoon and early evening.

Even in times of solar minimum, when F2 is rarely available, 10 meters still has some long distance possibilities. Sporadic E propagation can bring in signals from a hundreds to many thousands of miles away. Sporadic E on 10 meters is mainly a seasonal event, with late Spring and early Summer being prime time for the mode. A shorter, less-intense period occurs during mid-Winter, often between Christmas and New Year. Other, off-peak openings may be seen almost anytime. Even during solar minimum, F2 openings often occur on transequatorial paths, for example between Europe and Southern Africa or between Pacific North America and the Eastern Pacific islands.

In tropical latitudes 10 metres is open throughout the sunspot cycle, although propagation is often confined to other areas lying along the equator. For example, a good path from West Africa to the Caribbean exists on 10 metres even at solar minimum.

10-meter sub-bands

Although 10 meters has a worldwide amateur radio allocation, in some countries the use of portions of 10 meters is allocated by the government by license class, by signal mode and/or signal bandwidth. Beyond these regulations there is also a general voluntary band plan adhered to by amateurs throughout the world.

Worldwide frequency allocations

Worldwide 10 meter frequency allocations are [http://life.itu.int/radioclub/rr/hfband.htm specified by the ITU] .

Allocations in the United States are shown in the table below:

Key

Novice sub-bands

Named for the segment of 10 meters granted for use to old American Novice Class Amateur Radio license holders the Novice sub-bands consist of two frequency ranges; one for CW and Data operation the other for SSB phone operation.

Novice CW

28.000 MHz - 28.300 MHz Is a very active part of 10 meters for CW operation.

Novice Phone

28.300 MHz - 28.500 MHz is probably the most active part of the 10 meter band. Operation in this segment is almost exclusively SSB world wide.

The Beacon Sub-Bands

Because the propagation on 10 meters can vary drastically throughout the day, propagation beacons are very important to gauge the current conditions of the band. With some differences in each ITU Regions and also from country to country, the beacon sub-bands fall between 28.100 MHz and 28.300 MHz. ITU Region 1 is generally 28.190 MHz - 28.225 MHz and ITU Region 2 is generally 28.200 MHz - 28.300 MHz.

The AM Sub-Band

From 29.000 MHz to 29.200 MHz. Formerly-common practice was to use the band in 10 kHz steps: e.g. 29.010, 29.020, 29.030,... etc. This has not been the case since the 1970s, which saw an influx of surplus 23-channel CB equipment modified for use on the 10-meter amateur band. The surplus equipment would land in 10 kHz steps on the 5 kHz step such as: 29.015, 29.025, 29.035,... etc. Users of the surplus equipment also inherited those radios' odd channel spacing, which on the CB band skipped channels that were not used there, because they were set aside for remote control operations.

The Satellite Sub-Band

From 29.300 MHz to 29.510 MHz the satellite sub band allows amateur radio operaters to communicate with orbiting OSCARs.

atellite Operation on 10 Meters

Many OSCARs have either an uplink or a downlink in the 29 MHz range. Information about particular satellites and operational modes is available from [http://www.amsat.org/ AMSAT] .

As of the current writing, most if not all of the satellites actually using the sub band are non functional [http://www.amsat.org/amsat-new/satellites/status.php]

The FM Sub-Band

From 29.510 MHz to 29.700, The FM sub-band is usually channelized into repeater and simplex frequencies. The channels are commonly grouped into repeater inputs, simplex, and repeater output frequencies.

Repeater Input Channels:29.520, 29.540, 29.560, and 29.580 MHz.

Simplex Channel:29.600 MHz

Repeater Output Channels:29.620, 29.640, 29.660, and 29.680 MHz.

Repeater Operation on 10 Meters

Common practice for 10 meter repeaters is to use a 100 kHz negative offset for repeater operation. Due to the very few available repeater channels "odd-splits" (Offsets differing from 100 kHz) and non-standard frequencies are not uncommon. Because 10 meters can frequently open up to propagate globally most all 10 meter repeaters use a CTCSS sub-audible access tone. 16k wide signals with 5k deviation is normal in this band. 8k Narrow with 2.5k deviation can also be found.

Other FM Simplex Channels in use

29.300MHz is a common frequency to find JA hams on. British hams commonly use the 29.400 to 29.500 MHz band for FM as well with 29.400, 29.450, and 29.500 MHz being common. USA hams can be found on FM anywhere above 29.300 MHz, commonly on the above frequencies talking to overseas hams.

Aficionados

Due to its unique nature, 10 meters has a large following of hobbyists who center most of their time on this frequency band. The major group of enthusiasts is Ten-Ten [http://www.ten-ten.org/] which has been organized since the 1960s. A new group of enthusiasts has formed called the 10m/6m club [http://10-6-club.com/] .