helps radio amateurs and shortwave listeners to benefit from "grayline propagation", a virtual line which divides the earth into the day and the night side.
When one radio station is in the dusk and the opposite station is in the dawn, there is a possibility for so called "grayline propagation". At sunrise the D-layer builds up slowly and at sunset it disappears slowly again.
During this change, low frequencies are not absorbed but refracted by the D-layer and enter the F-layer with a much lower wave angle than normal.
In this way, longer distances can be used for propagation on the lower HF bands. "Grayline propagation" occurs in general from about 1.8 to 10 MHz, at which point the propagation paths are in the dark.
The program lets you calculate possible "grayline propagation" paths for your location to other DXCC countries for any given date, enabling you to output the data to the screen or a text file.
Grayline runs on
Windows 95/98/Me/NT/2000/Windows 10/11
and is available under the
Freeware
license
— the installer is 39 KB.
We’ve catalogued it under
Science and Engineering.
✓
Verified clean. Every Grayline build on SoftLookup is scanned for viruses, spyware, adware, trojans and backdoors. We re-test on every update.
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