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Message-ID: <003001c906e2$a904a800$0900a8c0@AM>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <200808251715030768.082E674C@smtp.wanadoo.fr>
Date: Mon, 25 Aug 2008 19:40:08 +0100
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Subject: LF: Re: Sensing loop
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Hi John. It depends what you are trying to do ?? It sounds like you are
trying to calibrate the loop effective height. Jim, Christos, and Dick
Rollema have done some work on this Dick recommends a toroidal transformwe
slipper onto an outer wire. I believe this will induce an accuarately known
current in the main loop and so facilitate a calibration. I am not sure I
have the get available in the mail archive but you may find that Rink
Strobbe has archived it in his tech papers (or maybe aerials) sections.

Best Wishes to You and Rosie
Alan G3NYK



----- Original Message -----
From: "John RABSON" <john.rabson@wanadoo.fr>
To: <rsgb_lf_group@blacksheep.org>
Sent: Monday, August 25, 2008 4:15 PM
Subject: LF: Sensing loop


I have a 2 metre square 8 turn loop which is series resonant on 138kHz.  To
calibrate this I am thinking of adding a single turn loop which can be fed
with a known current and therefore produce a known magnetic field.  Should
this turn be within the main winding or should it be a much smaller loop at
the centre?

John
F5VLF