10 meters
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The 10 meter amateur radio band is the highest of the High Frequency or "HF" bands. It is a large band, stretching from 28.000 MHz to 29.700 MHz.
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[edit] The History of 10 Meters
The Amateur Radio 10 Meter Band was created in 1928 after the International Radiotelegraph Conference was held in Washington, DC, USA.
Ham Radio lost the 300 kHz segment from 29.700 MHz to 30.000 MHz in 1947.
Launched in 1970 on a NASA flight OSCAR-5 was the first OSCAR to transmit on the Amateur 10 meter band and was built at University of Melbourne, Australia.
In the late 1970s with the impending American FCC ban of the sale of older 23 channel Citizens' band radio equipment that did not meet the more stringent type acceptance of the 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 them 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 in 1987
With the elimination of the CW requirement in the USA (23 Feb 2007), Technician class licenses with "no code" may operate up to 200 Watts CW and Phone SSB in a 10 Meter sub band.
[edit] Operating on 10 Meters
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.
[edit] Propagation Characteristics
Due 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 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 not long after sunrise, and often remain "open" until 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 perhaps Eastern Asia in the afternoon.
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 few hundred to a few thousand miles away. Sporadic E on 10 meters is mainly a seasonal event, with Summer being prime time for the mode. A shorter, less-intense period is seen mid-Winter, often between Christmas and New Year. Other, off-peak openings may be seen almost anytime. Even in 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.
[edit] The 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.
[edit] US Allocations
| 10 Meters | 28000 – 28300 | 28300 – 28500 | 28500 – 29700 |
|---|---|---|---|
| Novice / Technician | |||
| General, Advanced, Extra |
[edit] Key
| = CW, RTTY and data (US: < 1 KHz Bandwidth; Novice/Technician 200 watts PEP only) | |
| = CW, phone and image | |
| = CW and SSB phone |
[edit] The 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.
[edit] The Novice CW Portion
28.000 MHz - 28.300 MHz Is a very active part of 10 meters for CW operation.
[edit] The Novice Phone Portion
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.
[edit] The Beacon Sub-Bands
Because the propagation on 10 meters can vary drastically on 10 meters 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.
[edit] The AM Sub-Band
From 29.000 MHz to 29.200 MHz. Common practice was to use the band in 10 kHz steps. Originally 29.010, 29.020, 29.030,... etc. This has not been the case since the 1970s influx of surplus 23 channel CB equipment. 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 radio's odd channel spacing which on the CB band skipped channels that there were meant for remote control operations.
[edit] 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. Other uses of this frequency range are strongly discouraged.
[edit] Satellite 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 AMSAT.
[edit] 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, 29.530, 29.540, 29.550, 29.560, 29.570, 29.580 and 29.590 MHz.
Simplex Channels: 29.600 and 29.610 MHz
Repeater Output Channels: 29.620 29.630, 29.640, 29.650, 29.660, 29.670, 29.680 and 29.690 MHz.
[edit] 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 repeters use a CTCSS sub-audible access tone.
[edit] 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 [1] which has been organized since the 1960s.
| Medium (MF) and High frequency (HF) Amateur radio bands for ITU Region 2 | |||||||||
| MF | HF | ||||||||
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| 160 m | 80 m | 60 m | 40 m | 30 m | 20 m | 17 m | 15 m | 12 m | 10 m |
| 1.8 MHz | 3.5 MHz | 5 MHz | 7 MHz | 10.1 MHz | 14 MHz | 18.068 MHz | 21 MHz | 24.89 MHz | 28 MHz |
| 2 MHz | 4 MHz | region | 7.3 MHz | 10.15 MHz | 14.35 MHz | 18.168 MHz | 21.45 MHz | 24.99 MHz | 29.7 MHz |
