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. One of the five original shortwave bands allocated to amateurs in 1926, 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 communcation 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.
Much of this band is shared with broadcasters, and the full allocation is usually only available in the Americas. In most countries only the bottom 100 kHz or 200 kHz are available to amateurs.
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.
With its unique combination of intra- and inter-continental communications possibilites, 40 meters is considered a key band in building a winning shortwave contesting score, especially in the lower part of the sunspot cycle.
Summary
Frequency allocation
Japan
| License class | 7.000–7.025 | 7.030–7.100 | |
|---|---|---|---|
| All classes |
United Kingdom
| License class | 7.000–7.035 | 7.045–7.200 | ||
|---|---|---|---|---|
| All classes |
United States
| US License Class | 7.000–7.025 | 7.025–7.100 | 7.100–7.150 | 7.150–7.225 | 7.225–7.300 |
|---|---|---|---|---|---|
| Novice / Technician Plus | |||||
| General | |||||
| Advanced | |||||
| Extra |
Band plan
United States
| 7.035 | CW QRP calling frequency (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 |
See also
Shortwave bandsReferences
| 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
|
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