Return-Path: Received: (qmail 28481 invoked from network); 20 Jun 2001 15:24:13 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 20 Jun 2001 15:24:13 -0000 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit Received: (qmail 8118 invoked from network); 20 Jun 2001 15:23:13 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 20 Jun 2001 15:23:13 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15Cjhg-0007p6-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 20 Jun 2001 16:15:36 +0100 Received: from anchor-post-31.mail.demon.net ([194.217.242.89]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 15Cjhf-0007p0-00 for rsgb_lf_group@blacksheep.org; Wed, 20 Jun 2001 16:15:35 +0100 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from telemetry.demon.co.uk ([194.222.19.114]) by anchor-post-31.mail.demon.net with smtp (Exim 2.12 #1) id 15Cji8-0008iI-0V for rsgb_lf_group@blacksheep.org; Wed, 20 Jun 2001 16:16:04 +0100 Message-ID: <2awXzCA50JM7MwyD@telemetry.demon.co.uk> Date: Wed, 20 Jun 2001 13:55:21 +0100 To: rsgb_lf_group@blacksheep.org From: "Tom Boucher" Subject: Re: LF: Re: Static effects In-reply-to: <7D653C9C42F5D411A27C00508BF8803D55C4FA@pdw-mail-r1.dstl.gov.uk> MIME-Version: 1.0 X-Mailer: Turnpike Version 3.03a Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Andy G4JNT wrote: > > >Use the formula Vrms = 4.44.F.N.A.B to calculate the Minimum turns >needed on any given core, using a B of around 0.1 Tesla for a good safety >margin. All non-gapped ferrites designed for SMPSU transformers will have >more than enough inductance - up in the tens to hundreds of milli-henries - >when wound with enough turns to satisfy this equation. > Thanks Andy. I suspect I am not the only one on this reflector who regards the design of cored inductors as something of a black art! 73, Tom G3OLB