NVIS Test
- 07 October 2024
- West Georgia Amateur Radio Society
On October 5th, 2024 Carroll County ARES hosted a Near Vertical Incidence Skywave (NVIS) test, and WGARS was well represented at the event. A little over a dozen members joined in to test our ability to engage in local and regional communications using HF in the event local repeaters are unavailable.
From this article written by WX4BK: The rule of thumb for HF is that you'll get better DX the higher your antenna. The reason for this is that as a typical dipole antenna is raised higher, the take-off angle of MOST of the radio signals become shallower, closer to the horizon. This shallower angle provides for greater skip of the radio signal off the atmosphere, just like skipping a rock on water. Remember, however, that not all the signal is on one narrow angle, just the largest single component. It's like a Bell Curve, where angles above and below the take-off angle will have decreasing levels of signal.
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