On 01/06/2011 04:19 PM, Roger (K8RI) wrote:
> Many as it really doesn't help the performance. These deep grounds are
> for safety and have little effect on RF and particularly verticals. Of
> course we often hear of some one who has their vertical right over an
> old well and says how great it performs.. Surface or elevated radials
> make a great difference, deep grounds do not. The deeper you go the
> *less* effect they have on the RF efficency and radiation pattern.
The reason is simple. Current is pushed into one side of the
antenna and "pulled out" the other. (to over-simplify things)
In-between both sides of the antenna, the current has to travel
through whatever media there are. If the current travels mostly
through air, the power you push to your antenna is radiated.
If the current travels mostly through the ground, the power you
push down your coax will keep earthworms warm in winter.
Put your radial straight down into the ground, and you'll be
doing a lot of earthworm warming and less radiating.
Keep your radials above ground, you'll do more radiating.
Elevate your radials, and you'll do even less earthworm warming.
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