Return-Path: X-Spam-DCC: paranoid 1233; Body=3 Fuz1=3 Fuz2=3 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 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 tB4MHELE012994 for ; Fri, 4 Dec 2015 23:17:14 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1a4ycJ-0003ks-Qd for rs_out_1@blacksheep.org; Fri, 04 Dec 2015 22:14:15 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1a4ycJ-0003kj-Ib for rsgb_lf_group@blacksheep.org; Fri, 04 Dec 2015 22:14:15 +0000 Received: from parrot.netcom.co.uk ([217.72.171.49]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1a4ybK-0002Fs-W4 for rsgb_lf_group@blacksheep.org; Fri, 04 Dec 2015 22:14:14 +0000 Received: from sb.abelian.org (i-194-106-52-83.freedom2surf.net [194.106.52.83]) by parrot.netcom.co.uk (Postfix) with ESMTP id AEEDA3273A5 for ; Fri, 4 Dec 2015 22:03:57 +0000 (GMT) Received: from [127.0.0.1] (localhost [127.0.0.1]) by sb.abelian.org (Postfix) with ESMTP id C410828A0120 for ; Fri, 4 Dec 2015 22:12:58 +0000 (UTC) Message-ID: <56620FEA.7060308@abelian.org> Date: Fri, 04 Dec 2015 22:12:58 +0000 From: Paul Nicholson User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <8D2FC2AEF3A0D08-1488-1A0797@webmail-vd021.sysops.aol.com> <8D2FC914A8E0E4E-1038-20752A@webmail-vm010.sysops.aol.com> <56619CB7.4000501@abelian.org> <5661DD91.5070900@abelian.org> <5662026B.7020306@abelian.org> In-Reply-To: X-Scan-Signature: 64437c466041e93ffedda7fb96b22b71 Subject: Re: LF: More EbNaut 137.777 - Dec. 3/4 Content-Type: text/plain; charset=ISO-8859-1; 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 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 5562 Joe wrote: > compiled v0.3 but got a bailout 5000 symbols For some reason, you're still running the earlier version. ebkey -? gives you the version. Check the execution path and the gcc -o option. > tried 4K19A. That might be about 3dB too weak. I made a spectrogram of one of VO1NA's QRP transmissions which decoded with Eb/N0 = 0.2dB http://abelian.org/vlf/tmp/151204b.png That's after the modulation has been reversed to reconstruct the carrier. There isn't really a lot to see. The carrier is the intermittent line across the middle at 137.777 kHz and the bandwidth is that of an information bit. The Viterbi algorithm manages to pull out 46 bits from the broken line. The only way to really see the carrier is to plot the spectrum of the entire 1024 seconds in about 1mHz bandwidth, http://abelian.org/vlf/tmp/151204c.gif Spectrograms are popular but they're not really very good when looking at weak signals and mostly I use spectrum plots. -- Paul Nicholson --