Return-Path: Received: from rly-df03.mx.aol.com (rly-df03.mail.aol.com [172.19.156.16]) by air-df05.mail.aol.com (v125.7) with ESMTP id MAILINDF052-53b4ad519acde; Tue, 13 Oct 2009 20:22:16 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-df03.mx.aol.com (v125.7) with ESMTP id MAILRELAYINDF034-53b4ad519acde; Tue, 13 Oct 2009 20:22:06 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Mxrbw-0003if-J1 for rs_out_1@blacksheep.org; Wed, 14 Oct 2009 01:21:00 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Mxrbw-0003iW-7A for rsgb_lf_group@blacksheep.org; Wed, 14 Oct 2009 01:21:00 +0100 Received: from smtp817.mail.ird.yahoo.com ([77.238.189.17]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1MxraR-0004xf-Ck for rsgb_lf_group@blacksheep.org; Wed, 14 Oct 2009 01:19:27 +0100 Received: (qmail 39396 invoked from network); 14 Oct 2009 00:20:42 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btopenworld.com; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:In-Reply-To:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=xRB31DcUe8/8kZ8Eo1E5gLrqY0QmzjlnqQwerRtd7h07n5QMj0lyPjyu5H6zEWgR4lk+CNa3+21FBv9bksNebfI9AiyzKc1+fhbGHrdMTvN4ewdSAmFffHQJiYjh3kFJGl9GKYu6lfpli6V5Q0wxo+5W/ZSECOyS2W0C1aYgBpA= ; Received: from unknown (HELO JimPC) (james.moritz@86.179.130.177 with login) by smtp817.mail.ird.yahoo.com with SMTP; 14 Oct 2009 00:20:41 -0000 X-Yahoo-SMTP: qKIhhNCswBB2TTHr2BORWcGGR2mpopxhCcunGIxpCKQYiG07Q7UOhNo- X-YMail-OSG: qbtlGssVM1lySXzkItT68cSsF.tWJCrMCLCZWzNddk1vzDu8RbeRcnDXBxCgneBJc79v0HnN.9sIOWwO7lgl04ogB72x27PLoULplezQXizZiAA.fEi5M1VJ.MxmCupIuQgvB4DsBr4zZEsXE0gU6zGjptxowwGe.gJ_z3LydGZgyf7LLw7r07nGr3T1_bhc9wtsGsfaqeiQi93V1YfW_NKsW1Qdr5Rq7XT8f8tGGQ7udHEK_5RdBPRZxEoiMrkfNHLCCtuacKwaVw5A0VXqh_YL3AAO5uCRsdxw X-Yahoo-Newman-Property: ymail-3 Message-ID: From: "James Moritz" To: References: <425051.437.qm@web28506.mail.ukl.yahoo.com> <372276A0746748CEAEB6C24C08986671@AGB> In-Reply-To: <372276A0746748CEAEB6C24C08986671@AGB> Date: Wed, 14 Oct 2009 01:20:40 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6001.18000 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6001.18049 X-Karma: unknown: DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: ON / F6CNI / P on MF Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original 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=0.1 required=5.0 tests=MISSING_OUTLOOK_NAME 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-IP: 193.82.116.20 Dear Graham, LF Group, G0NBD wrote: ...>Looks like these low long wires radiate quite well at 500 , the high angle seems to help the 'short' skip ? Well, 20m high is quite high compared to most amateur antennas in use on 500k - But doing a few sums, a 20m high, 150m long aerial should have radiation resistance of 1.5ohms or over, and one might expect several ohms loss resistance if in a good location. So efficiency could be in the tens of percent, and, being about 1/4 wave long, presumably not requiring much if anything in the way of loss-increasing loading coils. So even with just 5W TX, Andy could in principle be achieving a few watts ERP. Cheers, Jim Moritz 73 de M0BMU