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Old September 11th 07, 08:39 AM posted to rec.radio.amateur.antenna
Jeff Jeff is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 158
Default Yagi height above ground

I see that height above ground affects the gain and the angle of the
main lobe. (actually all lobes) The info I've seen shows best gain and
lobe
formation somewhere between 1/4 and 1-1/2 wavelengths above ground.


This information is not really relevant to your situation. The best beam
formation is in free space, but at HF this is not practical, the antenna is
nearly always too close to the ground for the ground effects to be
neglected.
However at 2.4GHz you can get many wavelengths above the ground, and
practically the answer is higher the better. Ideally you should achieve line
of sight between stations, and also be sufficiently high so that intervening
ground does not encroach into what are known as the Fresnel Zones (the low
vale ones at least).

Regards
Jeff





So I have a 2.4Ghz yagi, does that mean I should put it 1/4 to 1-1/2
wavelengths
above ground? That means it would be 1-1/2" to 6" above ground.
Mike