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[195.171.43.25]) by mx.google.com with ESMTP id e4si17384654wik.48.2013.12.30.08.38.26 for ; Mon, 30 Dec 2013 08:38:27 -0800 (PST) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Vxflx-0003zY-2U for rs_out_1@blacksheep.org; Mon, 30 Dec 2013 16:32:57 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Vxflw-0003zP-J2 for rsgb_lf_group@blacksheep.org; Mon, 30 Dec 2013 16:32:56 +0000 Received: from relay2.uni-heidelberg.de ([129.206.210.211]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1Vxflu-00072f-5H for rsgb_lf_group@blacksheep.org; Mon, 30 Dec 2013 16:32:55 +0000 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay2.uni-heidelberg.de (8.13.8/8.13.8) with ESMTP id rBUGWqDP018375 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 30 Dec 2013 17:32:52 +0100 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id rBUGWq4q001653 for ; Mon, 30 Dec 2013 17:32:52 +0100 Message-ID: <52C1A026.4080909@iup.uni-heidelberg.de> Date: Mon, 30 Dec 2013 17:32:38 +0100 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <079a01cf057b$1af87300$50e95900$@comcast.net> In-Reply-To: <079a01cf057b$1af87300$50e95900$@comcast.net> X-Spam-Score: -2.4 (--) 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 Jim, Yes, this is the signal. They do not send a continuous tone but "beeps", thus the sidebands. You need to chance the FFT settings. First, "complex with internal frequency shift", centered to 11904.76 Hz. Next chance the decimate factor, increase it from 1 to 2 and then 4 and then 8 and so on and see what happens. The FFT input size can be 8192 or so. Enable "1 pixel per FFT bin" in the first register card of the audio settings and automatic scroll rate. Move the displayed frequency so you can see the lines. You will see the S/N becomes better when going slower, as expected. Others may give you additional advice... [...] Content analysis details: (-2.4 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [129.206.210.211 listed in list.dnswl.org] -0.1 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: d5ac66e7920295f519efeb68ecc59e6f Subject: Re: LF: Frequency Check Content-Type: multipart/alternative; boundary="------------020200020504030407040000" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,HTML_MESSAGE 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 Status: O X-Status: X-Keywords: X-UID: 2329 This is a multi-part message in MIME format. --------------020200020504030407040000 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello Jim, Yes, this is the signal. They do not send a continuous tone but "beeps", thus the sidebands. You need to chance the FFT settings. First, "complex with internal frequency shift", centered to 11904.76 Hz. Next chance the decimate factor, increase it from 1 to 2 and then 4 and then 8 and so on and see what happens. The FFT input size can be 8192 or so. Enable "1 pixel per FFT bin" in the first register card of the audio settings and automatic scroll rate. Move the displayed frequency so you can see the lines. You will see the S/N becomes better when going slower, as expected. Others may give you additional advice... 73, Stefan/DK7FC Am 30.12.2013 17:20, schrieb hvanesce: > > Stefan, > > My stable/accurate time reference (GPSDO) should arrive in two weeks; > in the meantime I am hoping to use 11904.76190 Hz (per your > suggestion, thanks) to assess my soundcard clock frequency offset. I > have been guessing (based on comparison with another uncalibrated but > stable oscillator) that the frequency offset of my soundcard gives > less than 1Hz error at 11904.76190 kHz. > > I have attached a screenshot captured over the last 24 hours, showing > a modulated signal centered at an indicated frequency (red marker) of > 11905.1884 which would have a 0.426 Hz offset from 11904.76190 Hz. > > The signal seems to be fading about 40dB on a 24-hour cycle, with a > minimum at ~ 2000 UT (clock times in my screen capture are Arizona > time, UT -- 7 hours). > > Could the modulated signal shown here be the 11904.76190 Hz signal? > > 73, Jim AA5BW > --------------020200020504030407040000 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello Jim,

Yes, this is the signal. They do not send a continuous tone but "beeps", thus the sidebands. You need to chance the FFT settings. First, "complex with internal frequency shift", centered to 11904.76 Hz. Next chance the decimate factor, increase it from 1 to 2 and then 4 and then 8 and so on and see what happens. The FFT input size can be 8192 or so. Enable "1 pixel per FFT bin" in the first register card of the audio settings and automatic scroll rate. Move the displayed frequency so you can see the lines. You will see the S/N becomes better when going slower, as expected.
Others may give you additional advice...

73, Stefan/DK7FC


Am 30.12.2013 17:20, schrieb hvanesce:

Stefan,

 

My stable/accurate time reference (GPSDO) should arrive in two weeks; in the meantime I am hoping to use 11904.76190 Hz (per your suggestion, thanks) to assess my soundcard clock frequency offset. I have been guessing (based on comparison with another uncalibrated but stable oscillator) that the frequency offset of my soundcard gives less than 1Hz error at 11904.76190 kHz.

 

I have attached a screenshot captured over the last 24 hours, showing a modulated signal centered at an indicated frequency (red marker) of 11905.1884 which would have a 0.426 Hz offset from 11904.76190 Hz.

 

The signal seems to be fading about 40dB on a 24-hour cycle, with a minimum at ~ 2000 UT (clock times in my screen capture are Arizona time, UT – 7 hours).

 

Could the modulated signal shown here be the 11904.76190 Hz signal?

 

73,  Jim AA5BW

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