Return-Path: Received: from mtain-dg12.r1000.mx.aol.com (mtain-dg12.r1000.mx.aol.com [172.29.65.20]) by air-dd08.mail.aol.com (v129.4) with ESMTP id MAILINDD084-86b04c45f46f318; Tue, 20 Jul 2010 15:09:35 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dg12.r1000.mx.aol.com (Internet Inbound) with ESMTP id 98D4C380000F0; Tue, 20 Jul 2010 15:09:33 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ObIB4-0003jc-83 for rs_out_1@blacksheep.org; Tue, 20 Jul 2010 20:08:30 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ObIB3-0003jT-Po for rsgb_lf_group@blacksheep.org; Tue, 20 Jul 2010 20:08:29 +0100 Received: from mailout-us.gmx.com ([74.208.5.67]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1ObIB2-0000IC-NA for rsgb_lf_group@blacksheep.org; Tue, 20 Jul 2010 20:08:29 +0100 Received: (qmail invoked by alias); 20 Jul 2010 19:08:20 -0000 Received: from 75-168-152-6.mpls.qwest.net (EHLO [192.168.1.100]) [75.168.152.6] by mail.gmx.com (mp-us003) with SMTP; 20 Jul 2010 15:08:20 -0400 X-Authenticated: #60769621 X-Provags-ID: V01U2FsdGVkX19YyUAgUzVYKY1StjOGKQgeYm407sBvLvX+GH3rWh Q+l3ScX3K8WZnE Message-ID: <4C45F3AA.1020702@gmx.com> Date: Tue, 20 Jul 2010 14:06:18 -0500 From: Mike-WE0H User-Agent: Thunderbird 2.0.0.24 (X11/20100317) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <4C44B478.7000109@iup.uni-heidelberg.de>,<4C45E1CA.6010003@iup.uni-heidelberg.de> In-Reply-To: X-Y-GMX-Trusted: 0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: RE: earth antenna Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: 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-aol-global-disposition: G x-aol-sid: 3039ac1d41144c45f46d3393 X-AOL-IP: 193.82.116.20 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) In the USA we call that a SWAG (Scientific Wild Ass Guess) Mike-WE0H Rik S wrote: > Stefan, > > based on the theory that an earth antenna is a loop and assuming that > the "height" of the loop remains unchanged, increasing the length from > 280m to 600m should increase the loop area (A) by 2.14 . > As the radiation resistance of a loop is proportional the A^2 the > radiation resistance should increase by 4.6. > If the loss resistance remains unchanged the improvement should > be almost 7dB. > > But notice the use of assuming, should and if ... so just a guess. > > 73, Rik ON7YD