Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id v9HJBZRA024328 for ; Tue, 17 Oct 2017 21:11:38 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1e4X4c-0007FD-AT for rs_out_1@blacksheep.org; Tue, 17 Oct 2017 19:58:42 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1e4X4b-0007F2-Bm for rsgb_lf_group@blacksheep.org; Tue, 17 Oct 2017 19:58:41 +0100 Received: from porthos.netcom.co.uk ([217.72.171.73]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1e4X4Y-0001uD-0I for rsgb_lf_group@blacksheep.org; Tue, 17 Oct 2017 19:58:40 +0100 X-DKIM-Result: Domain=abelian.org Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:To:Subject:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=9jCVG30jW3Rqw9KXI4nKXKa7dGpioRuqrdHZBLiH+6c=; b=aROiaRiA9TWvi3HHLUbwUKXuG+ aFuJYmUwKLIujEfQQ5AsPWKN5YXHEVzGsswBM7Eexdi2yrHTgg4HgkhCEB3bQd1zBFkx/+cFEqw81 pQynZ07UQ21ykngE/k7soNTA+hFa2AKcC58ISFkVWHG8Fje0RG1P00jYVowwNyENx2LM=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:47616 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1e4X4W-0003QS-LN for rsgb_lf_group@blacksheep.org; Tue, 17 Oct 2017 19:58:36 +0100 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id 1BA1E4000C1 for ; Tue, 17 Oct 2017 18:58:36 +0000 (UTC) To: rsgb_lf_group@blacksheep.org References: <15f2b478bc7-c10-5199@webjas-vac009.srv.aolmail.net> From: Paul Nicholson Message-ID: Date: Tue, 17 Oct 2017 18:58:35 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <15f2b478bc7-c10-5199@webjas-vac009.srv.aolmail.net> Content-Language: en-US X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - porthos.netcom.co.uk X-AntiAbuse: Original Domain - blacksheep.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - abelian.org X-Get-Message-Sender-Via: porthos.netcom.co.uk: authenticated_id: catchall@abelian.org X-Authenticated-Sender: porthos.netcom.co.uk: catchall@abelian.org X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Here's the nighttime signal along the 88 degree bearing to Amberg, http://abelian.org/vlf/tmp/171017d.gif Quite the opposite to what signal reports suggest? [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: c1f72e5acb1277e013f90c915ad7ad68 Subject: Re: VLF: EbNaut on 2 frequencies Content-Type: text/plain; charset=utf-8; format=flowed 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=0.9 required=5.0 tests=FROM_ENDS_IN_NUMS 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 Here's the nighttime signal along the 88 degree bearing to Amberg, http://abelian.org/vlf/tmp/171017d.gif Quite the opposite to what signal reports suggest? The daytime signal on 88 deg isn't significantly different to 307 deg (not much anisotropy apparent at these short ranges). I don't put much faith in this model but it serves to illustrate the complicated way that signals can vary as a function of range. A major difficulty at short ranges is the ground wave calculation, knowing how much power couples into the ground wave, and the average ground conductivity and permittivity. The precise ups and downs depend critically on the amplitude and phase of ground and several sky waves. At best it is in the right ballpark in terms of typical average field strengths. (I take some comfort that LWPC doesn't do any better.) But at least we can see that it's plausible to blame propagation for the different performance of signals at Stefan's two frequencies. -- Paul Nicholson --