Return-Path: Received: (qmail 10265 invoked from network); 21 Jan 2005 15:36:35 -0000 Received: from unknown (HELO ptb-spamcore01.plus.net) (192.168.71.1) by ptb-mailstore02.plus.net with SMTP; 21 Jan 2005 15:36:35 -0000 Received: from mailnull by ptb-spamcore01.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1Cs0oS-0004Vs-AI for dave@picks.force9.co.uk; Fri, 21 Jan 2005 15:35:05 +0000 Received: from [192.168.67.2] (helo=ptb-mxcore02.plus.net) by ptb-spamcore01.plus.net with esmtp (Exim 4.32; FreeBSD) id 1Cs0oS-0004Vp-7Z for dave@picks.force9.co.uk; Fri, 21 Jan 2005 15:35:04 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore02.plus.net with esmtp (Exim) id 1Cs0pt-000M5w-WB for dave@picks.force9.co.uk; Fri, 21 Jan 2005 15:36:34 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Cs0p6-0005uR-Ne for rs_out_1@blacksheep.org; Fri, 21 Jan 2005 15:35:44 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Cs0p6-0005u9-6l for rsgb_lf_group@blacksheep.org; Fri, 21 Jan 2005 15:35:44 +0000 Received: from mail-public.northwestel.net ([198.235.201.66] helo=yk-pvtmailprd-01.internal.messaging) by relay.thorcom.net with esmtp (Exim 4.43) id 1Cs0p3-0003rR-J6 for rsgb_lf_group@blacksheep.org; Fri, 21 Jan 2005 15:35:44 +0000 Received: from yk-asavprd-01.northwestel.net ([172.19.112.40]) by yk-pvtmailprd-01.internal.messaging (Sun ONE Messaging Server 6.0 Patch 1 (built Jan 28 2004)) with ESMTP id <0IAO00MYZBB1KS61@yk-pvtmailprd-01.internal.messaging> for rsgb_lf_group@blacksheep.org; Fri, 21 Jan 2005 08:35:25 -0700 (MST) Received: from localhost (localhost [127.0.0.1]) by yk-asavprd-01.northwestel.net (8.12.11/8.12.11) with ESMTP id j0LFZPHS012440 for ; Fri, 21 Jan 2005 08:35:25 -0700 Received: from yk-asavprd-01.northwestel.net ([127.0.0.1]) by localhost (yk-asavprd-01 [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 12391-01-2 for ; Fri, 21 Jan 2005 08:35:24 -0700 (MST) Received: from eagles (whthyt032-92.northwestel.net [205.234.32.92]) by yk-asavprd-01.northwestel.net (8.12.11/8.12.11) with SMTP id j0LFWvEX011215 for ; Fri, 21 Jan 2005 08:32:58 -0700 Date: Fri, 21 Jan 2005 15:32:52 +0000 From: "J. Allen" To: rsgb_lf_group@blacksheep.org Message-id: <007d01c4ffce$78e29e80$6401a8c0@eagles> MIME-version: 1.0 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 X-Mailer: Microsoft Outlook Express 6.00.2900.2527 X-Priority: 3 X-MSMail-priority: Normal X-Virus-Scanned: by amavisd-new at northwestel.net References: X-SPF-Result: relay.thorcom.net: 198.235.201.66 is neither permitted nor denied by domain of northwestel.net X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=failed,FORGED_RCVD_HELO=0.05 Subject: Re: LF: Coil Winding2, de VY1JA Content-type: text/plain; charset=iso-8859-1; format=flowed Content-transfer-encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Spam-Filtered: by PlusNet SpamCORE (v3.00) Alex, Thank you for running the calculation for me. I will wind the coil with 55 turns to a length of 160 mm and use the roller inductor for fine tuning. 73, J. ----- Original Message ----- From: "Alexander S. Yurkov" To: Sent: Friday, 2005/01/21 21:10 PM Subject: RE: LF: Coil Winding2, de VY1JA > On Fri, 21 Jan 2005, james moritz wrote: >> What is diameter of wire #17 in millimeters? I'll do aproximate >> estimation >> coil with Your formers. Though wire is coper... >> >> ...About 1.2mm, according to my ARRL handbook. > > Acording to estimation done number of turns to get about 700 Ohms is 55 > if former diameter is 320 mm. Optimal length of solinoid is about 160 mm. > If wire diameter is 1.2 mm then winding space/wire_diameter ratio will be > aproximatly optimal. This yelds Q about 300 but need turns to be not > close. If winding is by two wires close to each other then Q=240. > But there is an important notice in this case. If winding symmetry is not > ideal then parasitic current Ip shown on fig.1 in attaced file can > appeare. This can increase the loss. It will be better to connect two > equal parts of top load as shown on fig.2 not as on fig.1. This prevent > parasitic current appearence. If winding is close turn to turn with one > wire then as space/wire_diameter ratio as former_diameter/winding_length > ratio is not optimal. Then Q seems to be about 200. > > N.B. Numbers are very approximative, solid copper wire assumed. > > 73 de RA9MB/Alex > http://www.qsl.net/ra9mb > >