40 meters

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The 40 meters or 7 MHz band is a core amateur radio frequency band, spanning 7000 to 7300 kilohertz, allocated to radio amateurs in all countries worldwide. The 40 meter band was made available to amateurs in the United States by the Third National Radio Conference on October 10th, 1924. 40 meters is considered the most reliable all-season DX band, most useful for inter-continental communication at night. It is extremely useful for short to medium distance contacts from local contacts out to a range of 500–1500 km, depending on conditions, during the day. In higher latitudes, daytime inter-continental communication is also possible in winter, for example a good path often opens between Japan and northern Europe in the hours leading up to European midday from late November until late January, with a long path opening to the west coast of the United States and Canada after midday.

For many years the portion of the band from 7100-7300 kilohertz has been allocated to short wave broadcasters outside the Americas and not available to radio amateurs outside ITU Region 2. At the World Radio Conference WRC-03 in 2003 it was agreed that the broadcast stations would move out of the section 7100-7200 kiloherz on 29 March 2009 and that portion would become a worldwide exclusive amateur allocation afterwards. Discussions on releasing the remaining 100 kHz of the band to amateurs at a later date will continue in future conferences. Several European countries have now allowed amateur communication in the 7100-7200 kilohertz section on a shared non-interference basis as an interim measure.

Due to the 24 hour nature of the band, the wide variety of ranges that can be spanned with it, and its shared nature, it tends to be extremely crowded, and interference from other amateurs and broadcasters can be a serious limiting factor. In addition, amateurs in east and south-east Asia have suffered severe interference from illegal users in recent years.

Contents 1 Radio propagation characteristics 2 Frequency allocation 2.1 Japan 2.2 United Kingdom 2.2.1 IARU Region 1 2.3 United States 2.3.1 Key 3 Band plan 3.1 United States 4 See also 5 References

[edit] Radio propagation characteristics

This band allows both long distance communications (DX) between late afternoon and early morning hours and short distance NVIS contacts during daytime, especially during periods of high solar activity.

With its unique combination of intra- and inter-continental communications possibilities, 40 meters is considered a key band in building a winning shortwave contesting score, especially in the lower part of the sunspot cycle.

[edit] Frequency allocation

[edit] Japan

License class	7.000 – 7.025		7.030 – 7.100
All classes

[edit] United Kingdom

License class	7.000 – 7.035			7.045 – 7.200
All classes

[edit] IARU Region 1

40 Metres	7000 7035	7035 7040	7040 7043	7043 7100	7100 7200
IARU Region 1
Note: 7100-7200 allocated on a secondary non-interference basis

[edit] United States

US License Class	7.000 – 7.025	7.025 – 7.125	7.125 – 7.175	7.175 – 7.300
Novice / Technician
General
Advanced
Extra

[edit] Key

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

[edit] Band plan

[edit] United States

7.030	CW QRP calling frequency Accepted GB & Euro QRP calling.(QRP-L)
7.040	RTTY DX & CW QRP calling frequency
7.080-7.100	RTTY
7.110	CW QRP calling frequency (Novice)
7.112	CW QRP calling frequency (NorCal crystals)
7.171	SSTV
7.285	SSB QRP calling frequency
7.290	AM calling frequency

[edit] See also

Shortwave bands

[edit] References

• ARRLWeb: US Amateur Bands. Retrieved on 3 August, 2005.

• ARRLWeb: ARRL Band Plans. Retrieved on 3 August, 2005.

• RAC Web: Canada HF Band Plan. Retrieved on June 27, 2007.

• UK Amateur Radio Bandplans Band Plans. Retrieved on 3 August, 2005.

• Ham Radio QRP. Retrieved on 3 August, 2005.

• IARU Region 1 Bandplan. Retrieved on 3 August, 2005.

• IARU Region 2 Bandplan. Retrieved on 3 August, 2005.

• IARU Region 3 Bandplan. Retrieved on 3 August, 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