Return-Path: Received: (qmail 2334 invoked from network); 19 Sep 2002 13:34:05 -0000 Content-Transfer-Encoding: 8bit Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 19 Sep 2002 13:34:05 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 10998 invoked from network); 19 Sep 2002 13:33:51 -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; 19 Sep 2002 13:33:51 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 17s1OU-0005zk-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 19 Sep 2002 14:30:58 +0100 Received: from [212.164.44.2] (helo=astral.omskcity.com) by post.thorcom.com with esmtp (Exim 4.10) id 17s1OQ-0005zY-00 for rsgb_lf_group@blacksheep.org; Thu, 19 Sep 2002 14:30:55 +0100 Received: from fitec.omskcity.com (mu06.dialup2.infomsk.ru [212.164.44.118]) by astral.omskcity.com (8.9.3/8.9.3) with SMTP id UAA3d89d10b0187 for ; Thu, 19 Sep 2002 20:28:43 +0700 (OSS) Date: Thu, 19 Sep 2002 21:10:00 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-reply-to: <17a.ed80937.2abae90c@aol.com> Message-ID: MIME-Version: 1.0 Subject: Re: LF: IK2DED beacon and E field probe. Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Spam-Status: No, hits=-1.0 required=5.0tests=IN_REP_TO,DATE_IN_FUTURE_06_12version=2.31 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Hi, David and Group. On Thu, 19 Sep 2002 G0MRF@aol.com wrote: > My conclusion: The original estimate is too high and my estimate is probably > too low and the only sure way is to spend some time measuring. Your conclusion may be right. But I say "if antenna curent is 1 A..." and so on. Large resistance should decrease antenna curent and ERP should be much lower. This is why one need measure antenna curent to estimate ERP. Output TX power is not adeqate info. Also, it is worth to take into consideration Giulio's relatively high antenna (60 m!!!) Whithout top load this yeld 30 meters of effective height. If there is very large top load then ERP should be 4 times grater! If antenna height is 10 m (for example) then ERP is 9 times lower... ERP is mainly determed by antenna current and efffective height. If this is known then it is very simple to estimate radiated power. Certanly this is very aproximative estimation. But something is better then nothing :-) 73 de RA9MB/Alex http://www.qsl.net/ra9mb