Return-Path: Received: (qmail 285 invoked from network); 15 Apr 2002 15:02:13 -0000 Content-Transfer-Encoding: 8bit Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 15 Apr 2002 15:02:13 -0000 X-MSMail-Priority: Normal Received: (qmail 7740 invoked from network); 15 Apr 2002 12:20:01 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys.services.quay.plus.net with SMTP; 15 Apr 2002 12:20:01 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16x6mg-00013j-00 for rsgb_lf_group-outgoing@blacksheep.org; Mon, 15 Apr 2002 14:44:42 +0100 Received: from tlvsca.vim.tlt.alcatel.it ([194.243.74.245]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16x6mf-00013e-00 for rsgb_lf_group@blacksheep.org; Mon, 15 Apr 2002 14:44:41 +0100 Received: from tlvk7v (localhost [127.0.0.1]) by tlvsca.vim.tlt.alcatel.it (8.11.6/8.11.6) with SMTP id g3FC3fl18177 for ; Mon, 15 Apr 2002 14:03:41 +0200 (MET DST) Date: Mon, 15 Apr 2002 13:45:38 +0100 From: "Claudio Girardi" Subject: LF: General formula for inductance To: rsgb_lf_group@blacksheep.org X-Mailer: Z-Mail Pro 6.2, NetManage Inc. [ZM62_16H] X-Priority: 3 Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: I was able to find two old papers in the "Proceedings of the I.R.E." cited by Terman on the subject of inductance calculation; a general formula for the inductance of a single turn loop of (almost) any shape was proposed by Bashenoff in an article of November, 1928 and later verified also by Kalantaroff and Worobieff in another article in December, 1936. A simplified version of the formula is: L = 0.2 * p * ln((4 * S) / (d * p)) [uH] (all dimensions in meters) where p is the perimeter of the loop, S its area and d the wire diameter. The maximum error should be a few percent maximum for most shapes. A comparison of this formula with the other proposed for rectangular loops can be found at http://www.qsl.net/in3otd/rlsim.html 73, Claudio IN3OTD