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From: "J. B. Weazle McCreath" <weazle@hurontel.on.ca>
To: <rsgb_lf_group@blacksheep.org>
References: <001401c6bfcc$56290400$75be3b3e@fujitsu>
Date: Mon, 14 Aug 2006 22:09:18 +0100
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Subject: LF: Re: antenna current meter troubles
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Status: O

Hi Dick, LFers,

Coils wound on toroid cores are supposedly self shielded due
to the geometry of the core, but I think that you'd want more
than 4 inches of spacing from your loading coil.  Since there's
no difference in measuring the "antenna system" current in the
ground lead or the antenna lead, place your transformer core
over the ground lead.  That way, it's not exposed to high R.F.
voltages, as it would be if on the antenna lead, but also it will
let you place it close to the ground/earth rod, well away from
the R.F. field of the loading coil.  Locate the burden resistor
right at the toroid, then use twin shielded lead to the rest of
ammeter circuit which can be located a distance away. 

73, J.B., VE3EAR - VE3WZL
Solar and wind powered
EN93dr