Return-Path: Received: (qmail 24044 invoked from network); 2 Aug 2001 07:48:15 -0000 Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 2 Aug 2001 07:48:15 -0000 Received: (qmail 9766 invoked from network); 2 Aug 2001 07:47:57 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 2 Aug 2001 07:47:57 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15SD0c-0001Tn-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 02 Aug 2001 08:35:06 +0100 Received: from relay.dera.gov.uk ([192.5.29.49]) by post.thorcom.com with smtp (Exim 3.16 #2) id 15SD0a-0001Ti-00 for rsgb_lf_group@blacksheep.org; Thu, 02 Aug 2001 08:35:05 +0100 Content-Transfer-Encoding: 8bit Received: (qmail 15044 invoked from network); 2 Aug 2001 08:32:16 +0100 Received: from trtnmail.dera.gov.uk (146.80.9.56) by relay.dera.gov.uk with SMTP; 2 Aug 2001 08:32:16 +0100 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 28733 invoked from network); 2 Aug 2001 08:36:28 +0100 Received: (ofmipd 192.5.29.90); 2 Aug 2001 07:36:06 -0000 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id IAA18266; Thu, 2 Aug 2001 08:40:18 +0100 (BST) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: (qmail 21987 invoked from network); 2 Aug 2001 08:25:41 -0000 Received: from gauntlet.mail.dera.gov.uk (172.16.9.10) by baton.dera.gov.uk with SMTP; 2 Aug 2001 08:25:41 -0000 Received: by gauntlet.mail.dera.gov.uk; id IAA23341; Thu, 2 Aug 2001 08:13:14 GMT Received: from unknown(10.71.64.31) by gauntlet.mail.dera.gov.uk via smap (3.2) id xma023303; Thu, 2 Aug 01 08:13:09 GMT Received: from mailex.dera.gov.uk (unverified) by mailguard.dera.gov.uk (Content Technologies SMTPRS 4.1.5) with SMTP id for ; Thu, 2 Aug 2001 08:34:11 +0100 Received: (qmail 11685 invoked from network); 2 Aug 2001 07:22:39 +0100 Date: 2 Aug 2001 08:32:44 +0100 Message-ID: <7D653C9C42F5D411A27C00508BF8803D55C578@pdw-mail-r1.dstl.gov.uk> From: "Andrew Talbot" To: rsgb_lf_group@blacksheep.org X-5Received: from softdnserror (HELO cchecker.dstl.gov.uk) (192.168.248.52) by mailex.dstl.gov.uk with SMTP; 2 Aug 2001 06:22:39 -0000 X-4Received: from FRN-MAIL-R3.dstl.gov.uk (unverified) by cchecker.dstl.gov.uk (Content Technologies SMTPRS 4.1.2) with ESMTP id for ; Thu, 2 Aug 2001 07:22:28 +0100 X-3Received: by FRN-MAIL-R3 with Internet Mail Service (5.5.2650.21)id ; Thu, 2 Aug 2001 08:32:43 +0100 Subject: LF: RE: The CFA Antenna (again...) MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Yes. That is exactly what Maxwell stated and Hertz demonstrated 10 years later (I've just been re-reading a book on basic Electromagnetism). One field is generated from the other as soon as its value changes in time. Anyone who claims to be generating them separately probably only has a partial understanding of the whole process ! The realtive levels of E and H close to the antenna can vary widely depending on antenna topology, these are the near fields talked about a lot here recently, but in the far field both have to exist together, qith E and H related by 120.pi, the impedance of free space. As far as I can make out, all these wonder antennas just consist of a short E field element, with its resultant loss and high capacitance, both phased and resonated with a Loop like element with its high loss and inductive reactance. The two reactances are made to cancel, leaving a purely resistive element to be matched over a narrow bandwidth. If the bandwith is not narrow then the antenna is lossy. QED. Andy G4JNT > -----Original Message----- > From: Alberto di Bene [mailto:dibene@usa.net] > Sent: 2001-08-01 16:17 > To: LF Mailing List > Subject: LF: The CFA Antenna (again...) > > > It seems that the CFA Antenna now has a new incarnation, > under the name 'EH Antenna'. > > Look here : http://www.netcommander.com/home/w5qjr-/index.htm > > Or, for ham-related stuff, here : http://www.qsl.net/w0kph/ > > What makes me perplex, is the citation of 'independent E and > H fields'. > Unless I completely misunderstood what Maxwell said, the only case > when an E field can exist without a corresponding H field > (and viceversa), > is when they are stationary (in time) fields. Or am I wrong ? > > 73 Alberto I2PHD > > > -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.