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Message-ID: <002001cb0f2d$8f03d890$4001a8c0@lark>
From: "Alan Melia" <alan.melia@btinternet.com>
To: "RSGB LF Gp" <rsgb_lf_group@blacksheep.org>
References: <AANLkTim_OPzeU71kwNrrjce-s6gmyxs_eORjxDmvVyCL@mail.gmail.com>
Date: Fri, 18 Jun 2010 22:31:01 +0100
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Subject: LF: Re: Earth electrode loop area - I'm struggling
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Hi Roger A quick bit a fudging suggests about 6 (to 12)sq m. equivalent (not
guaranteed correct :-))  ). How does that align with your figs? It suggests
your aerial (loop) is not in the best
direction for him, or possibly you have a skin of good conductive ground
over the chalk, so you are not penertrating into the ground so much..

What is your distance from Jim??

Alan

----- Original Message ----- 
From: "Roger Lapthorn" <rogerlapthorn@gmail.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Friday, June 18, 2010 9:29 PM
Subject: LF: Earth electrode loop area - I'm struggling


> Please can someone help me with the maths? I've been trying to work out my
> effective loop area and I cannot get sensible answers. These are the
> measured or estimated numbers I have:
>
> Voltage across "loop"  = 24.48V rms  - measured
> Current flowing in "loop" = 0.15A - measured
> ERP (from far field levels) = 50-100uW (may be less) based on -18dB S/N
with
> M0BMU
>
> From these figures I should be able to work out the loop area, but either
my
> calculations are wrong or the figure is correct and the effective loop
area
> is very very small.
>
> Help!
>
> 73s
> Roger G3XBM
>
> -- 
> http://g3xbm-qrp.blogspot.com/
> http://www.g3xbm.co.uk
> http://www.youtube.com/user/g3xbm
> G3XBM    GQRP 1678      ISWL G11088
>