Return-Path: <majordom@post.thorcom.com> Received: (qmail 26015 invoked from network); 19 Jan 2001 18:53:56 -0000 Received: from unknown (HELO murphys-inbound.servers.plus.net) (212.159.14.225) by extortion.plus.net with SMTP; 19 Jan 2001 18:53:56 -0000 Received: (qmail 27321 invoked from network); 19 Jan 2001 18:56:39 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 19 Jan 2001 18:56:39 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 14Jgax-0001qI-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 19 Jan 2001 18:49:07 +0000 Received: from mail3.svr.pol.co.uk ([195.92.193.19]) by post.thorcom.com with esmtp (Exim 3.16 #1) id 14Jgaq-0001qB-00 for rsgb_lf_group@blacksheep.org; Fri, 19 Jan 2001 18:49:00 +0000 Received: from modem-81.beryllium.dialup.pol.co.uk ([62.136.3.81] helo=default) by mail3.svr.pol.co.uk with smtp (Exim 3.13 #0) id 14Jgaf-0002Em-00 for rsgb_lf_group@blacksheep.org; Fri, 19 Jan 2001 18:48:49 +0000 Message-ID: <000901c08247$aeaaec60$5103883e@default> From: "MAL HAMILTON" <MAL@g3kev.freeserve.co.uk> To: rsgb_lf_group@blacksheep.org Subject: LF: Re: Loading Coils Date: Fri, 19 Jan 2001 18:26:26 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.72.3110.5 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: <majordom@post.thorcom.com> -----Original Message----- From: boffin1 <boffin1@compuserve.com> To: INTERNET:rsgb_lf_group@blacksheep.org <rsgb_lf_group@blacksheep.org> Date: 18 January 2001 21:32 Subject: LF: Loading Coils I have just read some recent correspondence on this net concerning the pros and cons of placing the antenna loading coil in the shack or at the base of the vertical aerial wire. The loading coil is not just a matching device, it is also a primary source of vector potential and it is the vector potential, rather than its offspring, the magnetic and electric fields, which is the fundamental source of electromagnetic radiation. It is therefore advantageous to place the coil upright at the base of the antenna. Furthermore, as a large component of the vector potential is locally concentrated in this region, it may be possible to gain a few dBs by placing an aluminium or copper plate, somewhat larger than the diameter of the solenoid, a few centimetres under the solenoid, insulated from the earth but it may be connected directly to the TX ground terminal. (It reflects the vector potental instead of allowing it to be absorbed in the terrain, but DON'T stand on the plate to adjust the solenoid whilst running at full power !!!). I appreciate that some readers may not be au fait with vector potential and perhaps its fundamental role deserves to be lightly aired in the amateur radio journals. The PROF has now spoken and he knows his subject, others take notice. I am amazed that so many other so called experienced amateurs know so little about basic radio principles and especially LF. The supposition and nonsence published on here is unbelievable it just highlights how little most know about the subject. 73, Roger, G2AJV.