15-meter band

The 15-meter band (also called the 21-MHz band or 15 meters) is an amateur radio frequency band spanning the shortwave spectrum from 21 to 21.45 MHz. Almost all countries permit amateur communications on the entire band.

The 15-meter band is considered a DX band (i.e., used for long-distance communications). Since signals on 15 meters propagate primarily via reflection off of the F-2 layer of the ionosphere, the band is most useful for intercontinental communication during daylight hours, especially in years close to the solar maximum. However, the band also sees long-distance openings during solar minima, and into evening hours, and does not require high-power station equipment to make contacts even at these times.

Because the 15-meter wavelength is harmonically related to that of the 40-meter band, it is often possible to use an antenna designed for 40 meters on the 15-meter band, as well.

Contents 1 History 2 Frequency allocation 2.1 United States 2.1.1 Key 2.2 Canada[2] 2.2.1 Key 3 See also 4 References

History

The 15 meter band was created by the 1947 International Radio Conference of Atlantic City in part to compensate for the loss of the 160 meter band to amateurs by the introduction of Loran during World War II. The 15 meter band opened to amateurs for CW operation only in the United States on May 1, 1952 and telephony operations were authorized above 21250 kc. on March 28, 1953 ^[1]

Frequency allocation

United States

megahertz	21.000–21.025	21.025–21.200	21.200–21.225	21.225–21.275	21.275–21.450
Novice / Technician
General
Advanced
Extra

Key

	= CW, RTTY and data (US: < 1 kHz bandwidth)
	= CW, phone and image
	= CW only (US Novice/Technician: 200 W PEP maximum TPO)

Canada^[2]

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	21.000-21.070	21.070-21.090	21.090-21.125	21.125-21.1495	B	21.1505-21.335	21.335-21.345	21.345-21.450
Basic(+), Advanced

Key

	= CW only
	= CW, narrow band digital ( <= 500 Hz )
	= CW, narrow band digital ( <= 500 Hz ), wide band digital
	= Beacons
	= CW, phone
	= CW, phone, image ( <= 2700 Hz )

See also

• Shortwave bands

References

1. ^ "We Get 21 Mc." QST, June 1952, p. 29.
2. ^ Radio Amateurs of Canada HF/MF band plan http://www.rac.ca/en/rac/services/bandplans/hf/hfplan-20080711.pdf accessed 12 January, 2011

• "ARRLWeb: US Amateur Bands". http://www.arrl.org/FandES/field/regulations/bands.html. Retrieved August 3, 2005. 

• "ARRLWeb: ARRL Band Plans". http://www.arrl.org/FandES/field/regulations/bandplan.html. Retrieved August 3, 2005. 

• "UK Amateur Radio Bandplans Band Plans". http://www.rsgb.org/spectrumforum/bandplans/RSGB%20Band%20Plan%20master.htm. Retrieved August 3, 2005.  Click the 15 Meter button at the bottom of the page

• "Ham Radio QRP". http://www.ac6v.com/qrp.htm#CALL. Retrieved August 3, 2005. 

• "IARU Region 1 Bandplan" (PDF). http://www.iaru-r2.org/wp-content/uploads/region-1-hf-bandplan-2006.pdf. Retrieved January 1, 2006. 

• "IARU Region 2 Bandplan" (PDF). http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf. Retrieved January 1, 2008. 

• "IARU Region 3 Bandplan". http://www.jarl.or.jp/iaru-r3/r3bandplan.doc. Retrieved August 3, 2005. 

Range	Band	ITU Region 1	ITU Region 2	ITU Region 3
LF	2200 m	135.7 kHz - 137.8 kHz
MF	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		220.000 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 it is a de facto international amateur radio allocation. 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