I agree hundred percent of Rich's and Phil's opinions. A HF ground is not
necessary for yagi (dipole) or quad antennas on towers. This only needs a good
lightning ground.
More important is a free area around the directional antenna. A moist soil
will improve the reflected signals.
73,
Werner
DJ2HZ/VE7HBI
Phil Clements wrote:
> measures wrote:
>
> >? During the 1950s, the US Army discovered that HF only penetrates a few
> >inches into moist soil The need for a long ground that hits the water
> >table is yet another old wives's tale of ham radio. The lowest Z HF gnd
> >is large, flat, and near the surface.
>
> And an old wives tale of the commercial communication industry as well,
> huh Rich?
>
> Of course if the soil is "moist" there is no problem with the ground as
> moist soil provides the lossy conductivity one needs. But what if the
> soil isn't moist? Getting down to the ground water is the best way to
> ensure that you hit "moist" soil, particularly in some parts of the US.
> This is why the recommended grounding is with long, deep ground rods.
> You never know the absolute condx of your soil.
>
> 73,
>
> Jon
> KE9NA
>
> Rods driven into the ground have absolutely nothing to do with making
> an RF counterpoise or RF "drain." Ground rods serve only one purpose,
> and that is to protect your equipment from lightning damage.
>
> Polyphaser produces a good book on the subject of grounding, and
> shows how good engineering practice will pay off when the storms come
> your way.
>
> Ground radials, or a ground screen under an antenna system handle the
> RF end of things at a radio station. Rich is correct; they may lay on top
> of the ground, or be buried a few inches, it makes no difference. The
> reason radials are buried is to make the landscape look better at the
> antenna farm. Relying on ground rods to serve in place of a proper
> RF ground sends valuable RF into the lossy earth instead of its intended
> destination.
>
> (((73)))
> Phil, K5PC
>
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