The 15-meter band is an amateur radio

Amateur radio

Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...

 frequency band spanning the shortwave

Shortwave

Shortwave radio refers to the upper MF and all of the HF portion of the radio spectrum, between 1,800–30,000 kHz. Shortwave radio received its name because the wavelengths in this band are shorter than 200 m which marked the original upper limit of the medium frequency band first used...

 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

DXing

DXing is the hobby of tuning in and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications. Many DXers also attempt to receive written verifications of reception from the...

 band (i.e., used for long-distance communications). Since signals on 15 meters propagate primarily via reflection off of the F-2

Ionosphere

The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...

 layer of the ionosphere, the band is most useful for intercontinental communication during daylight hours, especially in years close to the solar maximum

Solar maximum

Solar maximum or solar max is the period of greatest solar activity in the solar cycle of the sun. During solar maximum, sunspots appear....

. 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 harmonic

Harmonic

A harmonic of a wave is a component frequency of the signal that is an integer multiple of the fundamental frequency, i.e. if the fundamental frequency is f, the harmonics have frequencies 2f, 3f, 4f, . . . etc. The harmonics have the property that they are all periodic at the fundamental...

ally related to that of the 40-meter band, it is often possible to use an antenna

Antenna (radio)

An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...

 designed for 40 meters on the 15-meter band, as well.

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

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 Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , RTTY Radioteletype Radioteletype is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations, later superseded by personal computers running software to emulate teleprinters, connected by radio rather than a wired link.The term radioteletype is used to...  and data (US: < 1 kHz bandwidth)
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , phone and image
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...  only (US Novice/Technician: 200 W PEP maximum TPO)

Canada

Canada is part of region 2 and as such is subject to the IARU band plan. Radio Amateurs of Canada

Radio Amateurs of Canada

Radio Amateurs of Canada , known in French as Radio Amateurs du Canada, is a member-based, non-profit organization of amateur radio enthusiasts in 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 Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...  only
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , narrow band digital ( <= 500 Hz )
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , narrow band digital ( <= 500 Hz ), wide band digital
	= Beacons
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , phone
	= CW Continuous wave A continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off... , phone, image ( <= 2700 Hz )