Return-Path: Received: (qmail 7143 invoked from network); 28 Dec 2003 21:06:26 -0000 Received: from unknown (HELO ptb-mxscan03.plus.net) (212.159.14.237) by ptb-mailstore02.plus.net with SMTP; 28 Dec 2003 21:06:25 -0000 Received: (qmail 32965 invoked from network); 28 Dec 2003 21:06:25 -0000 X-Filtered-by: Plusnet (hmail v1.01) X-Spam-detection-level: 11 Received: from ptb-mxcore03.plus.net (212.159.14.217) by ptb-mxscan03.plus.net with SMTP; 28 Dec 2003 21:06:24 -0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore03.plus.net with esmtp (Exim) id 1Aai7E-0008Sq-L6 for dave@picks.force9.co.uk; Sun, 28 Dec 2003 21:06:24 +0000 X-Fake-Domain: majordom Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Aai6h-0004V5-5M for rs_out@blacksheep.org; Sun, 28 Dec 2003 21:05:51 +0000 Received: from [212.135.6.11] (helo=smarthost1.mail.uk.easynet.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Aai6g-0004Uw-C4 for rsgb_lf_group@blacksheep.org; Sun, 28 Dec 2003 21:05:50 +0000 Received: from tnt-1-140.easynet.co.uk ([195.40.206.140] helo=bryan2) by smarthost1.mail.uk.easynet.net with smtp (Exim 4.10) id 1Aai6e-000FyS-00 for rsgb_lf_group@blacksheep.org; Sun, 28 Dec 2003 21:05:49 +0000 X-Bad-Message-ID: no DNS (bryan2) Message-ID: <006001c3cd86$3add4fc0$441686d4@bryan2> From: "captbrian" To: rsgb_lf_group@blacksheep.org References: <6.0.1.1.2.20031227144750.035a8d70@POP3.freeler.nl> <000101c3cd6d$6ee77de0$0dcefc3e@l8p8y6> Date: Sun, 28 Dec 2003 21:04:06 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: Re: Re: "T" versus "L"aerial Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.60 (1.212-2003-09-23-exp) on post.thorcom.com X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.60 X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-PN-SPAMFiltered: yes X-Spam-Rating: 2 I find it difficult to believe that there is any different loading seen at the bottom of two L's in parallel but with opposing horizontal parts from that seen by a single wire vertical to the Tee or that there is any different current distribution or radiated pattern. If there are those that do not then I ask:: what is the voltage difference between the two vertical wires at their respective junctions with their own horizontals ? Bryan G3GVB ----- Original Message ----- From: "hamilton mal" To: Sent: 28 December 2003 18:04 Subject: LF: Re: "T" versus "L"aerial ----- Original Message ----- From: Dick Rollema To: LF-Group Sent: Saturday, December 27, 2003 2:09 PM Subject: LF: "T" versus "L"aerial To All from PA0SE Further to my e-mail of 26 December I measured the field strength as radiated by the aerial in Inverted L-configuration. From this I found EMRP = 57 milliwatt. This confirms the benificial effect of top loading. The T-aerial radiated 140 milliwatt. So going from a single 20m top load wire for the "L" to 2 x 20m for the "T" resulted in an improvement by a factor 2.46 (3.9dB) in radiated power. The vertical part of the "T" consisted of an open wire feedline of 11m with the two wires connected in parallel in the attic shack. For the "L" one of the feedline wires was removed. I assume this did not appreciably affect the EMRP. HI Dick From your explanation using open wire feeder you are using an inv L with one feeder wire connected and with the 2 feeders strapped at the shack end then you have two inverted L antennas in parallel. A true T antenna has both feeder wires connected at the top as well as the bottom, in fact do not use open wire feeder, connect one wire to the centre of your T horizontal at the top and the bottom of your single wire to the loading coil and matching unit. 73 de Mal/G3KEV . 73, Dick, PA0SE