15 meters

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In telecommunications, 15 meters is a shortwave radio band used by amateur radio operators. The band is located at 21 MHz, and most countries permit amateur radio activity on at least the lower portion of the band.

Contents 1 Summary 2 Frequency allocation 2.1 United States 2.1.1 Key 3 Band plan 3.1 United States 4 See also 5 References

[edit] Summary

The 15 meter or 21 MHz band is a core amateur radio frequency band, which spans 21 to 21.45 MHz and is allocated to radio amateurs as primary users worldwide. 15 meters is considered a DX band, most useful for inter-continental communication during daylight hours, especially in years close to the solar maximum, since the 15 meter wavelength propagates primarily via reflection by the F-2 layer.

Because the frequency is an odd-order harmonic of the 40 meter amateur band, it is possible to obtain a close impedance match using an antenna cut for 40 meters on 15 meters, as well. Usually, though, users of the 15 meter band employ rotatable, multi-element directional antennas or "beams" to improve their communications with the particular area of the world they wish to reach.

[edit] Frequency allocation

[edit] United States

15 Meters	21000 – 21025	21025 – 21200	21200 – 21225	21225 – 21275	21275 – 21450
Novice / Technician
General
Advanced
Extra

[edit] Key

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

[edit] Band plan

[edit] United States

21.070-21.110	RTTY, data (US: < 1 KHz bandwidth)
21.340	SSTV

[edit] See also

Shortwave bands

[edit] References

• ARRLWeb: US Amateur Bands. Retrieved on August 03, 2005.

• ARRLWeb: ARRL Band Plans. Retrieved on August 03, 2005.

• UK Amateur Radio Bandplans Band Plans. Retrieved on August 03, 2005.

• Ham Radio QRP. Retrieved on August 03, 2005.

• IARU Region 1 Bandplan. Retrieved on August 03, 2005.

• IARU Region 2 Bandplan. Retrieved on August 03, 2005.

• IARU Region 3 Bandplan. Retrieved on August 03, 2005.

Medium (MF) and High frequency (HF) Amateur radio bands for ITU Region 2
MF	HF
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