Return-Path: Received: (qmail 11267 invoked from network); 13 Jan 2005 08:56:59 -0000 Received: from unknown (HELO ptb-spamcore01.plus.net) (192.168.71.1) by ptb-mailstore02.plus.net with SMTP; 13 Jan 2005 08:56:59 -0000 Received: from mailnull by ptb-spamcore01.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1Cp0mx-000Jim-LL for dave@picks.force9.co.uk; Thu, 13 Jan 2005 08:57:10 +0000 Received: from [192.168.67.3] (helo=ptb-mxcore03.plus.net) by ptb-spamcore01.plus.net with esmtp (Exim 4.32; FreeBSD) id 1Cp0mx-000Jij-IX for dave@picks.force9.co.uk; Thu, 13 Jan 2005 08:57:07 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore03.plus.net with esmtp (Exim) id 1Cp0mm-000944-G3 for dave@picks.force9.co.uk; Thu, 13 Jan 2005 08:56:56 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Cp0jC-00029O-D5 for rs_out_1@blacksheep.org; Thu, 13 Jan 2005 08:53:14 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Cp0jB-00029F-Qd for rsgb_lf_group@blacksheep.org; Thu, 13 Jan 2005 08:53:13 +0000 Received: from relay.sotline.ru ([80.89.139.226]) by relay.thorcom.net with esmtp (Exim 4.43) id 1Cp0j9-0001PQ-1u for rsgb_lf_group@blacksheep.org; Thu, 13 Jan 2005 08:53:13 +0000 Received: from astral.omskcity.com (mxs.sotline.ru [80.89.139.227]) by relay.sotline.ru (8.12.8p2/8.12.8) with ESMTP id j0D8qtki026988 for ; Thu, 13 Jan 2005 14:52:55 +0600 (OMST) (envelope-from fitec@omskcity.com) Received: from noname.nodomain.nowhere (host196.m02.dial.sotline.ru [81.176.51.196]) by astral.omskcity.com (8.x.x) with ESMTP id j0D8qmL3016167 for ; Thu, 13 Jan 2005 14:52:54 +0600 (OS) Received: from localhost (fitec@localhost) by noname.nodomain.nowhere (8.8.5/8.8.5) with SMTP id PAA00270 for ; Thu, 13 Jan 2005 15:11:28 GMT X-Authentication-Warning: noname.nodomain.nowhere: fitec owned process doing -bs Date: Thu, 13 Jan 2005 15:11:28 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-Reply-To: <003101c4f900$adda7d30$6401a8c0@eagles> Message-ID: MIME-Version: 1.0 X-SPF-Result: relay.thorcom.net: domain of omskcity.com designates 80.89.139.226 as permitted sender X-Spam-Score: 1.3 (+) X-Spam-Report: autolearn=no,DATE_IN_FUTURE_06_12=1.202,FORGED_RCVD_HELO=0.05 Subject: Re: LF: Re: Coil Winding, de J. Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.9 required=5.0 tests=DATE_IN_FUTURE_06_12 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) Content-transfer-encoding: 8bit Dear J, On Wed, 12 Jan 2005, J. Allen wrote: > > Since optimum Q in an inductor with solid wire requires an air space between > adjacent conductors equal to conductor diameter, would it make sense to wind > a coil with two varnished conductors in parallel and have the conductors in > tight contact? The idea of parallel conductors is to lower the Q, space the > conductors, and make winding the coil easier. Though it is a good idea. > I need to know is simply how big the elevated counterpoise should be in > meters to be effective but I do not understand how to extrapolate the > diameter of and effective counterpois in meters (its size) from the graphs. > Please explain use of the graphs for me. This figure us usefull to unerstend qualatively only dependance on conterpoise high. Also it is posible QUALATIVELY see how losses is chanded if conterpose is elevated or burred. This graph is for T or L antenna 20 m high with all wires radius 1 mm when conterpoise is equal to top load. Besides top load (and conterpoise length) should be much more then vertical wire length. Only for such a simple antenna geometry it is posible to derive analiticaly some formulas for ground loss resistance. Ro is some resistance depending on conterpoise lenght an soil conductivity. Formulas used to draw this figure was derived by me few years ago. Unfortunely I have forgot where is my writings with this formulas. Somewere they are but it is dificult to find them in my 'pile up' of different papers:-) I'll try to find. Also this formulas may be posible to find in archive of this list. But any way You can estimate ground loss for REAL antenna geometry if conterpoise is elevated. One should use a NEC-2 (EZNEC-2) with Sommerfeld-Norton ground description. Unfortunely this can not be done for burred conterpoise. Burred conterpoise require NEC-4. ELNEC (NEC-1) is not usefull to estimate ground loss at all. 73 de RA9MB/Alex http://www.qsl.net/ra9mb