Return-Path: Received: (qmail 6840 invoked from network); 21 Mar 1999 23:21:37 -0000 Received: from magnet.plus.net.uk (HELO magnet.force9.net) (195.166.128.26) by medusa.plus.net.uk with SMTP; 21 Mar 1999 23:21:37 -0000 Received: (qmail 22588 invoked from network); 21 Mar 1999 23:25:10 -0000 Received: from post.thorcom.com (194.75.130.70) by magnet.plus.net.uk with SMTP; 21 Mar 1999 23:25:10 -0000 Received: from troy.blacksheep.org ([194.75.183.50] ident=root) by post.thorcom.com with esmtp (Exim 2.04 #3) id 10OrXt-0006lc-01; Sun, 21 Mar 1999 23:22:17 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (from root@localhost) by troy.blacksheep.org (8.6.12/8.6.12) id XAA12300 for rsgb_lf_group-outgoing; Sun, 21 Mar 1999 23:17:43 GMT Received: from post.thorcom.com (root@post.unica.co.uk [194.75.183.70]) by troy.blacksheep.org (8.6.12/8.6.12) with ESMTP id XAA12168 for ; Sun, 21 Mar 1999 23:08:09 GMT Received: from arl-img-5.compuserve.com ([149.174.217.135]) by post.thorcom.com with esmtp (Exim 2.04 #3) id 10OrN9-0006FQ-00 for rsgb_lf_group@blacksheep.org; Sun, 21 Mar 1999 23:11:11 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: (from root@localhost) by arl-img-5.compuserve.com (8.8.6/8.8.6/2.18) id SAA26331 for rsgb_lf_group@blacksheep.org; Sun, 21 Mar 1999 18:07:14 -0500 (EST) Date: Sun, 21 Mar 1999 18:06:04 -0500 From: "Prof R. Jennison" Subject: LF: Re: Re: LF - early April 1st question To: rsgb_lf_group@blacksheep.org Message-ID: <199903211807_MC2-6ECD-7E30@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Disposition: inline Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org It is not essential to produce Both the E and H fields. Either one can produce the other. For example the toroidal antenna launches only an E field with an associated vector potential that produce, in the far field, an H field to accompany the E field. Similarly a loop antenna launches only an H field with its associated vector potential and as a result the E field forms in the far field. In both cases one ends up with a complete propagating electromagnetic field. With respect, take a look at the curl of the vectors. Roger, G2AJV.