Return-Path: X-Spam-DCC: paranoid 1481; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,RATWARE_GECKO_BUILD,SPF_PASS autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id uAC7DvLJ013476 for ; Sat, 12 Nov 2016 08:13:57 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1c5SP2-00025j-6f for rs_out_1@blacksheep.org; Sat, 12 Nov 2016 07:07:04 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1c5SP1-00025a-LX for rsgb_lf_group@blacksheep.org; Sat, 12 Nov 2016 07:07:03 +0000 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 4.87) (envelope-from ) id 1c5SOy-0005tV-Hc for rsgb_lf_group@blacksheep.org; Sat, 12 Nov 2016 07:07:02 +0000 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:To:References:Reply-To:Subject:Sender: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=VcVpqKwfZS4WIREFh8UGnqTBO7NcyXwWLsr/oNngD7o=; b=Jqjf+yjGr8Ed2DIzqihNkl1Pxe 68iHI4A1Z52Dl+2BeFGUpIF50i05optArCF4nUjPf7r6qk6kc5UulE6FLpZHZYo/bl1QgDcnWCy0L 3p6nwgQqP0ADme+xQaAlJtR4g/hFtgZ/r6ucoNCy0HTHHYz745AA3e5yXtDGz8l6qbIc=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:55261 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1c5SOw-0005Im-44 for rsgb_lf_group@blacksheep.org; Sat, 12 Nov 2016 07:06:58 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id 76832400415 for ; Sat, 12 Nov 2016 07:06:57 +0000 (UTC) References: <154c32c4dba-373a-24653@webprd-m58.mail.aol.com> <573CAF79.9040701@abelian.org> <573CBBF0.4030701@posteo.de> <573E5907.6020107@posteo.de> <573EA094.3040205@abelian.org> <573EF90F.1080201@posteo.de> <573FC4DA.3080107@abelian.org> <5740842D.3030000@posteo.de> <5744FA27.6010703@posteo.de> <57F56531.3060205@posteo.de> <5817DE39.9010506@posteo.de> <5818DDAB.7000804@abelian.org> <5819E3AA.3020906@posteo.de> <581A452F.6060506@abelian.org> <581A4BC6.9030106@abelian.org> <581A541E.9050406@abelian.org> <581A8098.8050909@posteo.de> <581C3027.8050003@abelian.org> <581C8660.1070709@posteo.de> <581C90C7.5030809@abelian.org> <581C95BC.6010602@posteo.de> <581DA8E4.5010701@abelian.org> <581DB9C0.10602@posteo.de> <581DCF2E.5090902@abelian.org> <581F9797.9060709@abelian.org> <5824A47D.3060108@posteo.de> <58260EC4.70903@abelian.org> <58261368.60901@posteo.de> <58261772.3050508@abelian.org> To: rsgb_lf_group@blacksheep.org From: Paul Nicholson Message-ID: <5826BF91.6070907@abelian.org> Date: Sat, 12 Nov 2016 07:06:57 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: <58261772.3050508@abelian.org> 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-Scan-Signature: 4e3b1488273adbbe9757d6bdd5adf219 Subject: Re: VLF: EbNaut transmissions on lower frequencies?, pre-tests: 6.47kHz Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit 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-Scanned-By: MIMEDefang 2.56 on 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 9438 On Oct 7th Stefan wrote: > f = 6470.00000 Hz > Start time: 07.10.2016 21:00:02 UTC > Symbol length: 80 s > Characters: 15 > CRC 16 > Coding 16K25A > Duration: ?? Something arround 44 hours? > Antenna current: 270 mA (ish) Copied 'DK7FC JN49IK 73' Eb/N0 = +1.1 dB BER = 37.8% Constant reference phase. Error map http://abelian.org/vlf/tmp/161112a.gif Using something that Markus suggested some time ago - to normalise the symbol amplitudes by the average signal amplitude. I've tried this before on various tests but never got an improvement, usually a small reduction of decode performance. But with this message straddling day and night it obviously helps a lot. I had to play with a range of averaging periods and don't yet know if I have the best one. -- Paul Nicholson --