Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dl04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 750913800008C; Mon, 17 Jun 2013 16:08:23 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1UofiC-0004Ap-4t for rs_out_1@blacksheep.org; Mon, 17 Jun 2013 21:07:36 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1UofiB-0004Ad-PE for rsgb_lf_group@blacksheep.org; Mon, 17 Jun 2013 21:07:35 +0100 Received: from smtp-vbr5.xs4all.nl ([194.109.24.25]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1UofiA-0006w8-1K for rsgb_lf_group@blacksheep.org; Mon, 17 Jun 2013 21:07:34 +0100 Received: from pc-roelof (ndb.demon.nl [82.161.81.65]) by smtp-vbr5.xs4all.nl (8.13.8/8.13.8) with ESMTP id r5HK7OcA019529 for ; Mon, 17 Jun 2013 22:07:33 +0200 (CEST) (envelope-from roelof@ndb.demon.nl) To: rsgb_lf_group@blacksheep.org References: <51BF39F4.5050500@iup.uni-heidelberg.de> <041C5051F6E04ACDAD3DAC6252BABD52@gnat> Date: Mon, 17 Jun 2013 22:07:24 +0200 MIME-Version: 1.0 From: "Roelof Bakker" Message-ID: In-Reply-To: <041C5051F6E04ACDAD3DAC6252BABD52@gnat> User-Agent: Opera Mail/12.15 (Win32) X-Virus-Scanned: by XS4ALL Virus Scanner X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hello Alan, >>> I recollect over long periods the best times at 136kHz were either just after sunset, or just before dawn<<< Talking about "just after sunset, or just before dawn" is not very precise as e.g. the time of the pre-dawn enhancement depends largely of the season. Looking at e.g. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [194.109.24.25 listed in list.dnswl.org] X-Scan-Signature: e90dcb17768c7e768f13e0721cc1c0c7 Content-Type: text/plain; charset=iso-8859-15; format=flowed; delsp=yes Subject: Re: LF: Re: LF propagation Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false x-aol-global-disposition: G x-aol-sid: 3039ac1d4ad251bf6cb57776 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hello Alan, >>> I recollect over long periods the best times at 136kHz were either just after sunset, or just before dawn<<< Talking about "just after sunset, or just before dawn" is not very precise as e.g. the time of the pre-dawn enhancement depends largely of the season. Looking at e.g. http://www.fourmilab.ch/cgi-bin/uncgi/Earth/action?opt=-p it is apparent that for our latitude the dawn period is much longer now than it is at the spring or autumn equinox when the grey line is marching vertical from east to west. At the moment the pre-dawn enhancement of reception of Canadian NDB's can be about one hour and a half before actual sun-rise, whilst in winter it can be about 15 minutes! 73, Roelof Bakker, pa0rdt