Return-Path: Received: (qmail 17680 invoked from network); 9 Jun 2002 07:47:15 -0000 Content-Transfer-Encoding: 8bit Received: from marstons.services.quay.plus.net (212.159.14.223) by mailstore with SMTP; 9 Jun 2002 07:47:15 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 21845 invoked by uid 10001); 9 Jun 2002 07:51:08 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from post.thorcom.com (193.82.116.70) by marstons.services.quay.plus.net with SMTP; 9 Jun 2002 07:51:08 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 17GxH6-0001Qj-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 09 Jun 2002 08:38:08 +0100 Received: from mail4.messagelabs.com ([212.125.75.12]) by post.thorcom.com with smtp (Exim 3.33 #2) id 17GxH5-0001Qd-00 for rsgb_lf_group@blacksheep.org; Sun, 09 Jun 2002 08:38:07 +0100 X-VirusChecked: Checked Received: (qmail 21337 invoked from network); 9 Jun 2002 06:35:56 -0000 Received: from merimac.us.gases.boc.com (HELO merimac) (204.149.80.4) by server-18.tower-4.messagelabs.com with SMTP; 9 Jun 2002 06:35:56 -0000 Received: by EXC_WIL04 with Internet Mail Service (5.5.2653.19) id ; Fri, 7 Jun 2002 10:01:33 -0400 Message-ID: From: "Ashlock,William" To: rsgb_lf_group@blacksheep.org Subject: LF: RE: Vertical angles Date: Fri, 7 Jun 2002 09:26:35 -0400 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) 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: >When several UK stations used loop antennas, I noticed that they had fading >at much shorter distances than those using Marconis. This was at about >300km, whereas Marconi users experience fading at about 500km. Possibly due to lower output? >Since this type of fading is caused by interference between the sky wave and ground >wave, it suggests that the loops had a higher angle of radiation. Is this a >function of loops, >or is it possible to steer the vertical angle by altering the feedpoint? No. Unlike high frequency, so-called 'large loops' (due to the size/WL ratio), low frequency loops are 'small loops' and have equal current throughout. Therefore the location of the feedpoint does not effect the wave angle. Bill A _____________________________________________________________________ This message has been checked for all known viruses by UUNET delivered through the MessageLabs Virus Control Centre. For further information visit http://www.uk.uu.net/products/security/virus/