Return-Path: Received: (qmail 26797 invoked from network); 18 Sep 2002 13:31:39 -0000 Content-Transfer-Encoding: 8bit Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 18 Sep 2002 13:31:39 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 12018 invoked from network); 18 Sep 2002 13:31:26 -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; 18 Sep 2002 13:31:26 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 17reuc-0003Z4-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 18 Sep 2002 14:30:38 +0100 Received: from [212.164.44.2] (helo=astral.omskcity.com) by post.thorcom.com with esmtp (Exim 4.10) id 17reuc-0003Yl-00 for rsgb_lf_group@blacksheep.org; Wed, 18 Sep 2002 14:30:38 +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 UAA3d887eb025a1 for ; Wed, 18 Sep 2002 20:25:04 +0700 (OSS) Date: Wed, 18 Sep 2002 21:06:20 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-reply-to: <169.13ec14d5.2ab9a03f@aol.com> Message-ID: MIME-Version: 1.0 Subject: Re: LF: Re: RX3QFM 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, Group. On Wed, 18 Sep 2002 G0MRF@aol.com wrote: > Just a thought, but isn't an antenna current of 2.75A a bit low for 0.5W ERP? > I recall running 8 Amps to a 300 foot wire with the top at 150 feet high and > Jim measured it at 0.5W ERP. Or does Vlad have something really high up? Vlad has Heff ABT 15 m (horizontal part of antenna is 150 m). So radiation resistanse is: Rrad = 1600*(Heff/lambda)^2=0.073 Ohm P = I^2*Rrad= 0.56 Watts. I do not know why your PWR is not high as follow: Rrad = 1600*(45/2200)^2 = 0.67 Ohm P = 8*8*0.67 = 43 Watts If only one end of wire has H=45m then Heff=22.5 m and P=11 Watts 73 de RA9MB/Alex http://www.qsl.net/ra9mb