10-meter band

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 28000 to 29700 kHz.^[1]

History

The 10-meter band was allocated on a worldwide basis by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927.^[2] 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.^[3]

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-metre band.^{[citation needed]}

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-metre band.

American Novice and Technician class licensees were granted CW and SSB segments on the 10 Metre Band as of 0001 UTC March 21, 1987.^[4]

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 metre band.

Operating

Being a very wide band in HF terms, many different transmission modes can be found on 10 metres. 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 top portion of the band.

Propagation characteristics

Due to its unique spot in the spectrum, 10 metres can occasionally be challenging to work. At peak times of the solar cycle when many sunspots appear on the Sun's surface, 10 metres can be alive with extremely long-distance signals, refracting from the F2 layer in the ionosphere. The 10 metre band is primarily a day-time band. As such, generally speaking, the most effective and efficient propagation of radio waves takes place during daylight hours, local time. During periods of increased sunspot activity, "band openings" may begin well before sunrise and continue into the night.

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 metres still has some long distance possibilities. Sporadic E propagation can bring in signals from a hundred to many thousands of miles away. Sporadic E on 10 metres 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-metre sub-bands

Although 10 metres has a worldwide amateur radio allocation, in some countries the use of portions of 10 metres 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 metre frequency allocations are specified by the ITU.^[5] The Radio Regulations of the International Telecommunication Union allow amateur radio operations in the frequency range from 28.000 to 29.700 MHz.

IARU Region 1

10 meters	28000-28070	28070-28190	28190-28225	28225-29510	29510-29520	29520-29700
IARU Region 1

IARU Region 2

10 meters	28000-28070	28070-28190	28190-28300	28300-29510	29510-29520	29520-29700
IARU Region 2

IARU Region 3

10 meters	28000-28050	28050-28150	28150-28190	28190-28200	28200-28300	28300-29700
IARU Region 3

USA

10 Metres	28000 – 28300	28300 – 28500	28500 – 29700
Novice / Technician
General, Advanced, Extra

Canada 10 metre band plan^[6]

Canada is part of region 2 and as such is subject to the IARU band plan. Radio Amateurs of Canada offers the bandplan below as a recommendation for use by radio amateurs in that country but it does not have the force of law and should only be considered a suggestion or guideline.

License class	28.000-28.070	28.070-28.120	28.120-28.1895	B	28.2005-28.225	28.225-28.300	28.300-28.320	28.320-28.670	28.670-28.690	28.690-29.300	29.300-29.510	G	29.520-29.690
Basic(+), Advanced

Key

	= CW only
	= CW, narrow band digital ( <= 500 Hz )
	= CW, narrow band digital ( <= 500 Hz ), wide band digital
	= CW, RTTY and data (US: < 1 kHz Bandwidth)
	= Beacons
	= CW, beacons
	= CW, phone, beacons
	= CW, phone
	= CW, phone, SSTV, Fax
	= CW, narrow band digital ( <= 500 Hz ), phone
	= Guard band - no transmissions allowed
	= FM, Digital Voice
	= CW, phone and image

Novice sub-bands

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

Novice CW

28.000 MHz - 28.300 MHz is a very active part of 10 metres for CW operation.

Novice Phone

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

The Beacon Sub-Bands

Because the propagation on 10 metres 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.

Ten Metre Propagation Beacons

A list of 10-metre propagation beacons is available.^[7]

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-metre 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.

Proposal: Simplex Channel, Worldwide calling AM: 29.000 MHz

The Satellite Sub-Band

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

Satellite Operation on 10 Metres

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.^[8]

As of the current writing, only AO-7´s 10m downlink is active.^[9]

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, Worldwide calling FM: 29.600 MHz

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

Repeater Operation on 10 Metres

Common practice for 10 metre 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. Since 10 metres can frequently open up to propagate globally, most 10 metre repeaters use a CTCSS sub-audible access tone. 16 kHz wide signals with 5 kHz deviation is normal in this band. 8 kHz narrow signals with 2.5 kHz deviation can also be found.

Other FM Simplex Channels in use

29.300 MHz 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 29.000 MHz, commonly on the above frequencies talking to overseas hams. 29.200 to 29.300 MHz is set aside in some area band plans for FM Simplex use.

Organizations

• Ten-Ten International
• Ham Radio Tube
• Hamwave
• Margarita & Martini 10-10 Chapter of Georgia

Aficionados

Due to its unique nature, 10 metres has a large following of hobbyists who centre most of their time on this frequency band. The major group of enthusiasts is Ten-Ten which has been organized since the 1960s.^[10]

References

v t e International amateur radio frequency allocations
Range	Band	ITU Region 1	ITU Region 2	ITU Region 3
LF	2200 m	135.7 kHz - 137.8 kHz
MF	600 m	472 kHz - 479 kHz
	160 m	1.810 MHz - 1.850 MHz	1.800 MHz - 2.000 MHz	1.800 MHz - 2.000 MHz
HF	80 / 75 m	3.500 MHz - 3.800 MHz	3.500 MHz - 4.000 MHz	3.500 MHz - 3.900 MHz
	60 m1	5.250 MHz - 5.450 MHz
	40 m	7.000 MHz - 7.200 MHz	7.000 MHz - 7.300 MHz	7.000 MHz - 7.200 MHz
	30 m2	10.100 MHz - 10.150 MHz
	20 m	14.000 MHz - 14.350 MHz
	17 m2	18.068 MHz - 18.168 MHz
	15 m	21.000 MHz - 21.450 MHz
	12 m2	24.890 MHz - 24.990 MHz
	10 m	28.000 MHz - 29.700 MHz
VHF	6 m	50.000 MHz - 52.000 MHz1	50.000 MHz - 54.000 MHz	50.000 MHz - 54.000 MHz
	4 m1	70.000 MHz - 70.500 MHz
	2 m	144.000 MHz - 146.000 MHz	144.000 MHz - 148.000 MHz	144.000 MHz - 148.000 MHz
	1.25 m		222.000 MHz - 225.000 MHz
UHF	70 cm	430.000 MHz - 440.000 MHz	420.000 MHz - 450.000 MHz3	420.000 MHz - 450.000 MHz3
	33 cm		902.000 MHz - 928.000 MHz
	23 cm	1.240 GHz - 1.300 GHz
	13 cm	2.300 GHz - 2.450 GHz
SHF	9 cm	3.400 GHz - 3.475 GHz3	3.300 GHz - 3.500 GHz	3.300 GHz - 3.500 GHz
	5 cm	5.650 GHz - 5.850 GHz	5.650 GHz - 5.925 GHz	5.650 GHz - 5.850 GHz
	3 cm	10.000 GHz - 10.500 GHz
	1.2 cm	24.000 GHz - 24.250 GHz
EHF	6 mm	47.000 GHz - 47.200 GHz
	4 mm3	75.500 GHz1 - 81.500 GHz	76.000 GHz - 81.500 GHz	76.000 GHz - 81.500 GHz
	2.5 mm	122.250 GHz - 123.000 GHz
	2 mm	134.000 GHz - 141.000 GHz
	1 mm	241.000 GHz - 250.000 GHz
THF	Sub-mm	Some administrations have authorized spectrum for amateur use in this region.
1 This is not mentioned in the ITU's Table of Frequency Allocations, but individual administrations may make allocations under Article 4.4 of the ITU Radio Regulations. See the appropriate Wiki page for further information. 2 HF allocation created at the 1979 World Administrative Radio Conference. These are commonly called the "WARC bands". 3 This includes a currently active footnote allocation mentioned in the ITU's Table of Frequency Allocations.
See also: Radio spectrum · Electromagnetic spectrum