I have a different picture of penetration versus soil types.
The usual method for specifying RF peentration is to calculate the value
where the field has declined to 1/e where e is the base for natural logs. In
other words, where the intensity has fallen to 37% of the reference value.
The resulting penetration at 1.8 mHz for some common soil types is:
dry sandy soil 165 feet
dry clay soil 117 feet
moist low conductivity soil 37 feet
wet sandy soil 9 feet
moist high conductivity soil 4 feet
In other words, then entire length of a ground rod is effective for anything
but the wettest, most conductive soil.
Chuck
----- Original Message -----
From: "Donald Chester" <k4kyv@hotmail.com>
To: <topband@contesting.com>
Sent: Friday, August 20, 2004 4:16 PM
Subject: Re: Topband: Two Wire Beverage Query...
Unless you have very poor soil conductivity,
> the rf isn't going to penetrate the soil very far, and a ground rod driven
> below where the rf penetrates could just as well be made of fibreglass. I
> just lay radials on top of the ground, and if they are not taken up, they
> very soon become buried under the thatch, and eventually sod. The latest
> addition to my beverage project doesn't even use a ground rod.
>
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