Return-Path: Received: (qmail 10811 invoked from network); 4 Jan 2001 18:31:15 -0000 Received: from unknown (HELO murphys-inbound.servers.plus.net) (212.159.14.225) by excalibur.plus.net with SMTP; 4 Jan 2001 18:31:15 -0000 Received: (qmail 23739 invoked from network); 4 Jan 2001 18:25:55 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 4 Jan 2001 18:25:55 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 14EEye-0000x7-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 04 Jan 2001 18:19:04 +0000 Received: from irwell.zetnet.co.uk ([194.247.47.48] ident=root) by post.thorcom.com with esmtp (Exim 3.16 #1) id 14EEyb-0000x2-00 for rsgb_lf_group@blacksheep.org; Thu, 04 Jan 2001 18:19:02 +0000 Received: from oemcomputer (man-009.dialup.zetnet.co.uk [194.247.41.11]) by irwell.zetnet.co.uk (8.9.3/8.9.3/Debian/GNU) with SMTP id SAA03640 for ; Thu, 4 Jan 2001 18:18:51 GMT X-Authentication-Warning: irwell.zetnet.co.uk: Host man-009.dialup.zetnet.co.uk [194.247.41.11] claimed to be oemcomputer Message-ID: <006601c0767b$3e0f02c0$0b29f7c2@oemcomputer> From: "John Rabson" To: rsgb_lf_group@blacksheep.org References: <3A531C89.2032.BB2276@localhost> <3A54B293.13773.446063@localhost> Subject: Re: LF: Large and small antennas Date: Thu, 4 Jan 2001 18:22:01 -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 5.00.2615.200 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: ----- Original Message ----- From: Mike Dennison To: Sent: Thursday, January 04, 2001 5:27 PM Subject: Re: LF: Large and small antennas > Well, here we get into the very muddy waters of just how you > measure ERP - seemingly a very imprecise science. Also the far > more interesting area of matching the antenna to the propagation > medium (sometimes referred to as ionospheric matching). An > example of this is the idea that a "useless" horizontal antenna - or > the horizontal part of an L - can in some cases give an improvement > on the pure vertical because of the way the signal is presented to > the ionosphere. And this is another area where the unreliability of > the technique makes it a taboo area for the commercials but a > potential source of gold for us. If I can run out a quarterwave at 136 kHz will this be any use e.g. for NVIS paths? 73 de John Rabson G3PAI