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ДНД на КВ антени спрямо антенната височина - mzk - 23-09-2021
ДНД на хоризонтални диполи
https://practicalantennas.com/applications/nvis/
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The gain also depends on the ground conditions. This plot shows gain vs. height for an 80m dipole over 4 types of ground, to give a sense of the variation:
Notice that the peak of the gain curves are very broad, somewhere between 0.13 wavelengths (10m, 35 feet) and 0.25 wavelengths (20m, 65 feet) depending on soil characteristics. However, for any of the soil conditions, a dipole at 0.07 wavelengths (6m or 20 feet), as shown by the red arrow, is within about 3 dB of the peak, and, especially for portable operation, this may be more practical height. With an inverted vee, try to keep the ends at least half that height above the ground. At lower heights, ground losses increase, although contacts are often still possible with the antenna 1m (3 feet) above the ground, or even less.
http://www.dx-antennas.com/Height%20versus%20take%20off%20angle.htm
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TO = take off angle
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ДНД на вертикални диполи / маркони