Just to illustrate N4ZR's comment, I fired up HFTA and created a
fictious terrain, one that a very good local terrain near the antenna,
but had a lot of high stuff in the distance. If you used the website
for calculating HAAT of this terrain, it should give you -270 ft. Sounds
bad, huh?
I used a dipole at 14MHz and compared the response of this dipole to a
dipole over flat ground. At an elevation angle of 6 degrees, the dipole
over my special fictious terrain beat the dipole over flat ground by 12 dB.
Jerry, K4SAV
Pete Smith wrote:
>For HF operation, HAAT is fundamentally irrelevant. Average terrain elevation
>from 43KM to 16 KM is, at most, only a small part of the picture. The best
>tool available for hams is HFTA (HF Terrain Analysis), which relates the
>effects of local topography to the arrival angles of the desired signals.
>
>Line-of-sight frequencies are a different matter, of course.
>
>73, Pete N4ZR
>
>
>
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