Vhf Whip
What is "Antenna dimension D" Fraunhofer equation describes distance?
Radio Commuications learning, distance from Fraunhofer where d = 2 * D ^ 2/Lamda require large "dimenssion D" of the antenna, as in the diameter of the antenna? For example, if I have a VHF transmitting antenna at 175MHz (wavelength 1.7 million), and is a kind of whip antenna with a diameter of, say, 10 cm (0.1 m), the far field is at a distance of more 2 * d ^ 2/lamda = 2 * (a ^ 2) / 1.7 = 0.00177M? Thanks to look at the antenna and the correction of what is "the size of the antenna" is defined, then it is two in one dimension 1/2lamda antenna (1.7 / 0.85 =), so d = 2 *. 85 ^ 2/1.7 = 0.85 m?
D is the largest physical dimension of the antenna linear. A quarter of a wave with a suitable base is generally regarded as the equivalent of half a wave, I expect to be 1.7 million.
FT-817ND RX Contest delle Sezioni VHF
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