Return-Path: X-Spam-DCC: paranoid 1233; 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=-2.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL 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 t0B95OK2026339 for ; Sun, 11 Jan 2015 10:05:24 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1YAEIH-00070k-Ky for rs_out_1@blacksheep.org; Sun, 11 Jan 2015 08:54:45 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1YAEIG-00070b-P8 for rsgb_lf_group@blacksheep.org; Sun, 11 Jan 2015 08:54:44 +0000 Received: from mail-we0-f169.google.com ([74.125.82.169]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.84) (envelope-from ) id 1YAEIE-0005Pk-Ed for rsgb_lf_group@blacksheep.org; Sun, 11 Jan 2015 08:54:43 +0000 Received: by mail-we0-f169.google.com with SMTP id m14so14425470wev.0 for ; Sun, 11 Jan 2015 00:54:41 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to; bh=G+uI0HhVNifLmzmx1oYYfFLuwBG9c6O0gu9FLoeZUNk=; b=mRUEEHlq8BftzCYHN0AYRuM7qnANwV/EgI3ZMBsOKGc1g17ZqHr6c3/RMWQ62WgtDA h6kWNP5JkJJUSf11yzM/xVqaZv4ckEEROnylZORpqZA3cnsszxGP3miySXaX0DyoAsnZ tHex0/KGrE6Q1ji3LWgNoXnhLxVNs3kUSAmErEZe3P56R1Ez0uk7pLzU0Lr8Kw+DJJAM kntsT6SQnqr6KqlGEaqTA5aMuufQeG3IT26ZJFu6rUxjENVl7fiaLHUln4DupgwIrzOA 4bPNZetWcm+LilwpoQMH4d2sDgStJQDUSvh/rD7T4eksMwZdeR8gM5hFrLvlXeLCu4ml sjYA== X-Received: by 10.194.108.162 with SMTP id hl2mr46402796wjb.134.1420966481197; Sun, 11 Jan 2015 00:54:41 -0800 (PST) Received: from [192.168.1.101] ([178.16.253.2]) by mx.google.com with ESMTPSA id ej10sm5361217wib.2.2015.01.11.00.54.40 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 11 Jan 2015 00:54:40 -0800 (PST) Mime-Version: 1.0 (Mac OS X Mail 8.1 \(1993\)) From: John Rabson X-Priority: 3 In-Reply-To: Date: Sun, 11 Jan 2015 09:54:35 +0100 Message-Id: References: <20150108220755.GA20377@cs.utwente.nl> <54AF0F8C.8030106@virginbroadband.com.au> <20150110211701.GN29958@cs.utwente.nl> To: rsgb_lf_group@blacksheep.org X-Mailer: Apple Mail (2.1993) X-Scan-Signature: 1e15d6d6179985f133b43d42d658878a Content-Type: text/plain; charset=iso-8859-1 Subject: Re: LF: Eb/N0 values for amateur modes 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 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by paranoid.lipkowski.org id t0B95OK2026339 Status: O X-Status: X-Keywords: X-UID: 1942 Andy, G4JNT, had a piece in CREGJ in 2012 about assessing SNR for voice, CW and single tones. See http://bcra.org.uk/pub/cregj/index.html?j=78. John F5LVF > On 10 Jan 2015, at 23:13, Alan Melia wrote: > > Hi Pieter, Dave G3YXM and I did some quick and dirty estimations of QRSS about 10 years ago on 136kHz I cant remember whether we did DFCW where the main advantage is that it is faster, but the decode threshold is about the same as QRSS It is a little subjective but the results seemed reasonably what we might suspect. > > They may be on his web-site still www.wireless.org I think the we only considered fully reading the ID and Dave reduced power until it was not possible to decode. The results were in line with the FFT resolution used, but we have no measured values. > > I believe someone in the States also did some tests, John W1TAG could probably help there. They may be on the LWCA web-site. > > Best Wishes > Alan > G3NYK > G3NYK > > ----- Original Message ----- From: "Pieter-Tjerk de Boer" > To: > Sent: Saturday, January 10, 2015 9:17 PM > Subject: Re: LF: Eb/N0 values for amateur modes > > >> >> On Fri, Jan 09, 2015 at 10:15:24AM +1100, edgar wrote: >> >>> In your email, in which mode grouping would DFCW 180 fit? >> >> Not in any, really. I'm not aware of any (published) experiments having >> been done to establish decoding thresholds for it, which I could use >> to put it in the table. >> >> Compared to regular CW transmitted at the same (peak) power, DFCW has >> about 3 dB more average power because the transmitter is on continuously, >> so just because of that, it should give better performance at the same >> _peak_ power level. However, whether the performance difference is more >> or less than 3 dB, and thus whether it is better or worse than CW at the >> same _average_ power (as normally used for Eb/N0 calculation), is harder >> to predict. >> >> Regards, >> Pieter-Tjerk, PA3FWM >> > > john.rabson07@gmail.com Researching history of RABSON, BLACKSHAW, GAUNTLETT, VERLANDER and ROBSONNE