Difference between revisions of "HF Propagation"
From The RadioReference Wiki
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* [http://www.fourmilab.ch/cgi-bin/uncgi/Earth/action?opt=-p Earth View] great for seeing Greyline | * [http://www.fourmilab.ch/cgi-bin/uncgi/Earth/action?opt=-p Earth View] great for seeing Greyline | ||
* [http://www.fourmilab.ch/cgi-bin/uncgi/Earth?imgsize=320&opt=-l&lat=37.0833&ns=North&lon=72.4167&ew=West&alt=35785&img=learth.evif Planetary View] another Greyline view | * [http://www.fourmilab.ch/cgi-bin/uncgi/Earth?imgsize=320&opt=-l&lat=37.0833&ns=North&lon=72.4167&ew=West&alt=35785&img=learth.evif Planetary View] another Greyline view | ||
+ | * [http://science.nasa.gov/headlines/y2008/30apr_4dionosphere.htm 4D View of Ionosphere] NASA website | ||
==Software== | ==Software== |
Revision as of 20:09, 7 May 2008
Radio and TV signals aren't always limited to traveling line of sight distances. On HF this is commonly caused by refraction (bending) of the signal at the upper layers of the atmosphere known as the ionosphere. On frequencies higher than this, while solar activity plays a role, Earth based weather
events are the most common cause of propagation. These links explore several sites, and software,
that can be used to help predict how a HF signal will propagate. For propagation topics above 30 Mhz,
please see our DXing Above 30 Mhz article.
If you're just getting started in the HF hobby, AE4RV's Propagation Primer is an excellant place to start. Note that you need the most up to date Flash software to view this site.
Links and Online Maps
- Links
- Online Maps
- Grey Line Map
- Hourly Propagation Maps via HFPack
- Earth View great for seeing Greyline
- Planetary View another Greyline view
- 4D View of Ionosphere NASA website