Return-Path: Received: (qmail 7122 invoked from network); 6 Jun 2002 16:07:27 -0000 Content-Transfer-Encoding: 8bit X-Priority: 3 Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 6 Jun 2002 16:07:27 -0000 X-MSMail-Priority: Normal Received: (qmail 25990 invoked from network); 6 Jun 2002 16:06:57 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 6 Jun 2002 16:06:57 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 17FzX9-000220-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 06 Jun 2002 16:50:43 +0100 Received: from astral.infomsk.ru ([212.164.44.2] helo=astral.omskcity.com) by post.thorcom.com with esmtp (Exim 3.33 #2) id 17FzX8-00021t-00 for rsgb_lf_group@blacksheep.org; Thu, 06 Jun 2002 16:50:42 +0100 Received: from fitec.omskcity.com (mu07.dialup2.infomsk.ru [212.164.44.119]) by astral.omskcity.com (8.9.3/8.9.3) with SMTP id WAA3cff83d249bb for ; Thu, 6 Jun 2002 22:46:26 +0700 (OSS) Date: Thu, 6 Jun 2002 23:27:21 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org Subject: Re: LF: Counterpoise Experiment In-reply-to: <5.1.0.14.0.20020605115057.00aa4808@gemini.herts.ac.uk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Someone more... On Wed, 5 Jun 2002, James Moritz wrote: > > With no counterpoise, the antenna loss resistance at 136kHz was 37ohms. > With the counterpoise as above, Rloss dropped to 32ohms, a reduction of > about 14%. With antenna current of 5A, 1A (ie 20%) of RF current was > returned through the counterpoise. Part of current returning through groung is 4/5 = 0.8 And resistance 32/37=0.86 It seems if disconnect the ground loss resistance to be about ((0.86 - 0.8)/0.8)*37= 3 ohm!!! But it is worth to isolate TX box from antenna/conterpoise system by ferrite transformer. Loading coil should be in series with secondary (!!!) wire of transformer, not primary. 73 de RA9MB/Alex http://www.qsl.net/ra9mb