Return-Path: Received: (qmail 27406 invoked from network); 9 Jun 2002 11:06:22 -0000 Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 9 Jun 2002 11:06:22 -0000 Received: (qmail 18940 invoked from network); 9 Jun 2002 11:05:51 -0000 Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 9 Jun 2002 11:05:51 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 17H0Sy-0001vl-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 09 Jun 2002 12:02:36 +0100 Received: from mta06-svc.ntlworld.com ([62.253.162.46]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 17H0Sx-0001vg-00 for rsgb_lf_group@blacksheep.org; Sun, 09 Jun 2002 12:02:35 +0100 Received: from oemcomputer ([213.104.96.100]) by mta06-svc.ntlworld.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with SMTP id <20020609110233.VBEF4119.mta06-svc.ntlworld.com@oemcomputer> for ; Sun, 9 Jun 2002 12:02:33 +0100 Message-ID: <000f01c20fa4$f57f2980$786168d5@oemcomputer> From: "mike.dennison" To: rsgb_lf_group@blacksheep.org References: Subject: LF: Re: RE: Vertical angles Date: Sun, 9 Jun 2002 12:01:07 +0100 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 5.50.4133.2400 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: > >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? No, I really mean fading, not weaker signal. The fading was typically slow - perhaps over 30-60 seconds. > >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. So, presumably my first theory is correct - loops have a higher angle of radiation than Maconis. Mike, G3XDV http://www.lf.thersgb.net ====================