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LF: Earthing systems

To: "LF-Group" <[email protected]>
Subject: LF: Earthing systems
From: "Alan Melia" <[email protected]>
Date: Sat, 26 Jun 2004 00:19:01 +0100
Reply-to: [email protected]
Sender: [email protected]
Hi all, I offer  below, culled from the LWCA message board, a description of
an "improved" eathing system for LF.  To me this does not make sense, but
maybe I am missing something...any thoughts anywhere?? I can see that the
small inductance of the very short (45feet..14m) "radial" could "impede" the
passage of current collected at the remote ground spike, but I do not really
see what is happening. We may have to wait for the article to hear the full
measurement detail. I am worried that he has measured the soil conductivity
at 60Hz ....this has little relation to ground loss effects at 136 to
180kHz....though maybe if it drops at 60Hz it is somewhat better at 136 ??
---------------------------------
Hi Eric,
I'm working on an article for an upcoming LOWDOWN on the system, but
briefly, it goes like this; at the far end of EACH radial is a 4 or 8 ft
ground rod (most are 8') with a series capacitor between the radial end and
the ground rod. This capacitor is VERY important as it cancels out the XL of
the buried radial and really maximizes the available current in said
radial.Here, on a 45' radial(the longest) it requires a 0.047uF value. On
the 20 footers,(the shortest) it runs about 0.15 uF. The bad news is I have
134 radials!! Lots of expense and lots of exercise.(I LOVE to experiment)
Hope this info helps you. 73, Ed G.
-------------------------------

0.047nF resonates with 29uH at 136 and about 16uH at 180Khz....my belief is
that a short wire (less than a 1/4wave is capacitive not inductive at LF,
though a straight piece of insulated wire measured away from resonance will
have some inductance.

My though is if this really does work it could be helpful tho those with
short back gradens, but I worry that Ed may not have measured the aerial
system properly and could maybe be fooling himself (I've done it myself
before I started to use an RF bridge)

I am not trying to nit-pick on Ed's energetic works, but would like to ask
him the right questions (maybe suggest some different measurements) so that
we could, maybe, understand what is happening.

Cheers de Alan G3NYK
[email protected]




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