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[195.171.43.25]) by mx.google.com with ESMTP id i8si1626338laa.48.2013.10.18.14.32.31 for ; Fri, 18 Oct 2013 14:32:31 -0700 (PDT) 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; dkim=pass (test mode) header.i=@comcast.net Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1VXHdm-0000d4-9F for rs_out_1@blacksheep.org; Fri, 18 Oct 2013 22:31:26 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1VXHdl-0000cv-Fz for rsgb_lf_group@blacksheep.org; Fri, 18 Oct 2013 22:31:25 +0100 Received: from qmta14.westchester.pa.mail.comcast.net ([76.96.59.212]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1VXHdi-0001Tw-DG for rsgb_lf_group@blacksheep.org; Fri, 18 Oct 2013 22:31:24 +0100 Received: from omta17.westchester.pa.mail.comcast.net ([76.96.62.89]) by qmta14.westchester.pa.mail.comcast.net with comcast id ec6c1m0041vXlb85ElXL1n; Fri, 18 Oct 2013 21:31:20 +0000 Received: from JAYDELL ([71.234.119.9]) by omta17.westchester.pa.mail.comcast.net with comcast id elXK1m00i0CFS1j3dlXKsl; Fri, 18 Oct 2013 21:31:20 +0000 Message-ID: <001201cecc49$629c4350$6401a8c0@JAYDELL> From: To: References: <001601cecc44$3539dcb0$6d01a8c0@DELL4> Date: Fri, 18 Oct 2013 17:31:19 -0400 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=q20121106; t=1382131880; bh=Ye/j9c0tNmpIO0ZRtCzFOqMqmXbaIJlJA75ProeSZiY=; h=Received:Received:Message-ID:From:To:Subject:Date:MIME-Version: Content-Type; b=ihwbVu2vMnYZyYbuokR8an2kmLzIMaK/2d8QoB1sMb7IiF5KuLudJSnKVTrEuNyM7 MlppYwLFTv7OQMeuaO0lrl0rlCJ7hLGbgnL2a/ZMIdPltu1XEyUux2OZQbdN3yhWjA o2n1DgTZnA7NJDAPHHdoYla97uU+IpizdgJtMpMhW2XlV9pl9xD4MzllmHSyOU4GYv jQ0D8US3PsX9Uw1O24IIpRkHfIbEA26sUVL6zTBuETXOMed2LwH9JO/SSywIRGJ/9w Eq0SeNunwcJz9V/pZv4eHvlOFSKqZbGT+UMlWZDaoLuj8zSyKl5yVJ167q2OUr4nx5 qt1AKkHy10aJw== X-Spam-Score: -0.4 (/) 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: T/A OPDS enthusiasts It appears that I mistakenly ran with a known setup issue last night ... so my reported SNR numbers should not be considered accurate. The issue is now resolved and the setup is running. Hope to catch both Stefan and Markus tonight ... maybe VO1NA can be encouraged to join in as well. Have only received Joe's OPDS32 on one ocassion several weeks back. [...] Content analysis details: (-0.4 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [76.96.59.212 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (jrusgrove[at]comcast.net) -0.0 SPF_PASS SPF: sender matches SPF record -0.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 571129b349252c35b2bc09d7a1c6d0f3 Subject: Re: LF: T/A OPDS DK7FC Content-Type: multipart/alternative; boundary="----=_NextPart_000_000E_01CECC27.DB34E230" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.8 required=5.0 tests=HTML_20_30,HTML_MESSAGE, NO_REAL_NAME 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: 3036 This is a multi-part message in MIME format. ------=_NextPart_000_000E_01CECC27.DB34E230 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit T/A OPDS enthusiasts It appears that I mistakenly ran with a known setup issue last night ... so my reported SNR numbers should not be considered accurate. The issue is now resolved and the setup is running. Hope to catch both Stefan and Markus tonight ... maybe VO1NA can be encouraged to join in as well. Have only received Joe's OPDS32 on one ocassion several weeks back. Jay W1VD WD2XNS WE2XGR/2 WG2XRS/2 ----- Original Message ----- From: Markus Vester To: rsgb_lf_group@blacksheep.org Sent: Friday, October 18, 2013 11:41 AM Subject: Re: LF: T/A OPDS DK7FC Stefan, Jay, John, the "96%" number shows the temporal overlap between the receive period (ie the duration of the currently used FFT, about 35 minutes) and the identified Op sequence (33 minutes). With 10 minutes spacing between subsequent FFTs, the sequence does not always fit completely into one of the slots. so it says that 96% of the sequence was included in the evaluation. However the missing part has only neglegible impact on the detection sensitivity. Ideally Opera can be treated as an AM signal, with a central carrier and modulation sidebands around it. The "2mHz" bandwidth figure refers to the bandwidth of the carrier, which should be as small as possible. Opds applies some smoothing to the power spectrum and then tries to measure the -10 dB bandwidth of the central peak. Stable and phase coherent signals consistently show less than 3 mHz bandwidth. An intermediate width up to about 30 mHz typically indicates a coherent signal but with a slight thermal drift. Even higher bandwidth (~ 100 mHz) are mostly due to incoherent keying, ie random phase dashes caused by stopping the TX oscillator or divider during gaps. Opds internally uses an "autofocus" concept similar to synchroneous demodulation, where the central spectral peak is used as a phase reference. Narrower carriers produce better demodulated SNR. For fading or incoherent signals, the phase has to be tracked faster or even on a dash-by-dash basis, which is much less efficient. The "dBOp" column is showing SNR according to José's Opera scale, which is approximately based on average power. It shows 4 dB more negative values than the standard WSPR scale, ie. carrier power in 2.5 kHz. A marginally decode with WSPR-15 would need -38 dB, and an Opera signal with same PEP would then show as -42 dBOp. For a coherent signal, the Opds-32 threshold should be around -50 dBOp, which in theory is 8 dB better than WSPR-15 and 11 dB better than standard Opera-32. Please be aware that the SNR figures shown in opds results can sometimes be inaccurate. With an incoherent signal, often not all of the carrier power is captured during the bandwidth measurement, producing a low or invalid SNR reading. The SNR measurement also doesn't work well for strong signals (> -20 dBOp), eg for DK7FC who should really be plus several dB here. So why was Stefan's TA signal not stronger last night? My guess is that TA propagation just didn't extend into central Europe: While UK and duch stations received Bob well on 74 kHz, little or nothing at all apperared on Hartmut's and my 74 kHz grabbers. Best 73, Markus (DF6NM) PS The weather has improved here, so I have put out the TX antenna for a possible joint TA session tonight. From: Stefan Schäfer Sent: Friday, October 18, 2013 2:36 PM To: rsgb_lf_group@blacksheep.org Subject: Re: LF: T/A OPDS DK7FC Hi John, Jay, Markus, OK. Well, it seems to work. But i can't value the results. Why is it only 96% and what is the meaning of 2 mHz here? Seems the S/N is rather low. Condx must have been poor. Were there other reports from US stns? 73, Stefan/DK7FC Am 18.10.2013 13:05, schrieb John Andrews: Stefan, Markus, Jay, Results from last night: 2013-10-18 05:09:25 DK7FC 5981km 137560.016Hz 2mHz -42.8dBOp 96% 20.6dB 2013-10-18 04:29:25 DK7FC 5981km 137560.016Hz 2mHz -44.8dBOp 96% 17.8dB 2013-10-18 03:49:23 DK7FC 5981km 137560.016Hz 2mHz -44.0dBOp 96% 20.3dB 2013-10-18 03:09:23 DK7FC 5981km 137560.017Hz 2mHz -43.7dBOp 96% 19.0dB 2013-10-18 02:29:23 DK7FC 5981km 137560.016Hz 3mHz -47.5dBOp 96% 17.9dB 2013-10-18 01:49:23 DK7FC 5981km 137560.016Hz 3mHz -46.4dBOp 80% 16.8dB John, W1TAG ------=_NextPart_000_000E_01CECC27.DB34E230 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
T/A OPDS enthusiasts
 
It appears that I mistakenly = ran with a=20 known setup issue last night ... so my reported = SNR numbers=20 should not be considered accurate. The issue is now resolved = and the setup=20 is running. Hope to catch both Stefan and Markus tonight ... maybe = VO1NA=20 can be encouraged to join in as well. Have only received Joe's OPDS32 on = one=20 ocassion several weeks back.
 
Jay W1VD  WD2XNS  = WE2XGR/2 =20 WG2XRS/2  
 
----- Original Message -----
From: Markus=20 Vester
Sent: Friday, October 18, 2013 11:41 AM
Subject: Re: LF: T/A OPDS DK7FC

Stefan, Jay, John,
 
the "96%" number shows the temporal = overlap=20 between the receive period (ie the duration of the currently=20 used FFT, about 35 minutes) and the identified Op sequence = (33=20 minutes). With 10 minutes spacing between subsequent FFTs, the = sequence=20 does not always fit completely into one of the slots. so it says = that 96%=20 of the sequence was included in the evaluation. However the missing=20 part has only neglegible impact on the detection=20 sensitivity.
 
Ideally Opera can be = treated as an AM=20 signal, with a central carrier and modulation sidebands around it. The = "2mHz"=20 bandwidth figure refers to the bandwidth of the carrier, which should = be as=20 small as possible. Opds applies some smoothing to the power spectrum = and then=20 tries to measure the -10 dB bandwidth of the central peak. = Stable and=20 phase coherent signals consistently show less than 3 mHz bandwidth. An = intermediate width up to about 30 mHz typically indicates a = coherent=20 signal but with a slight thermal drift. Even higher bandwidth (~ = 100 mHz)=20 are mostly due to incoherent keying, ie random phase dashes = caused=20 by stopping the TX oscillator or divider during gaps.
 
Opds internally uses an "autofocus" = concept=20 similar to synchroneous demodulation, where the central spectral peak = is used=20 as a phase reference. Narrower carriers produce better=20 demodulated SNR. For fading or incoherent signals, the phase has to be = tracked=20 faster or even on a dash-by-dash basis, which is much less=20 efficient.
 
The "dBOp" column is showing SNR = according to=20 Jos=E9's Opera scale, which is approximately based on average power. = It shows 4=20 dB more negative values than the standard WSPR scale, ie. carrier = power in 2.5=20 kHz. A marginally decode with WSPR-15 would need -38 dB, and an = Opera=20 signal with same PEP would then show as -42 dBOp. For a coherent = signal, the=20 Opds-32 threshold should be around -50 dBOp, which in theory is 8 = dB=20 better than WSPR-15 and 11 dB better than standard = Opera-32.
 
Please be aware that the SNR figures = shown in=20 opds results can sometimes be inaccurate. With an incoherent=20 signal, often not all of the carrier power is captured during the = bandwidth measurement, producing a low or invalid SNR=20 reading. The SNR measurement also doesn't work well for = strong=20 signals (> -20 dBOp), eg for DK7FC who should really be plus = several dB=20 here.
 
So why was Stefan's TA signal not = stronger last=20 night? My guess is that TA propagation just didn't = extend into=20 central Europe: While UK and duch stations received Bob well on 74 = kHz, little=20 or nothing at all apperared on Hartmut's and my 74 kHz=20 grabbers.
 
Best 73,
Markus (DF6NM)
 
PS The weather has improved = here,=20 so I have put out the TX antenna for a possible joint TA session=20 tonight.
 

From: Stefan = Sch=E4fer
Sent: Friday, October 18, 2013 2:36 PM
Subject: Re: LF: T/A OPDS DK7FC

Hi John, Jay, Markus,

OK. Well, it seems to work. But i = can't=20 value the results. Why is it only 96% and what is the meaning of 2 mHz = here?
Seems the S/N is rather low. Condx must have been = poor.
Were there=20 other reports from US stns?

73, Stefan/DK7FC

Am = 18.10.2013=20 13:05, schrieb John Andrews:
Stefan, Markus, Jay,

Results = from last=20 night:

2013-10-18 05:09:25 DK7FC   5981km=20 137560.016Hz   2mHz -42.8dBOp  96% 20.6dB
2013-10-18 = 04:29:25 DK7FC   5981km 137560.016Hz   2mHz=20 -44.8dBOp  96% 17.8dB
2013-10-18 03:49:23 = DK7FC  =20 5981km 137560.016Hz   2mHz -44.0dBOp =20 96% 20.3dB
2013-10-18 03:09:23 DK7FC   5981km=20 137560.017Hz   2mHz -43.7dBOp  = 96% 19.0dB
2013-10-18=20 02:29:23 DK7FC   5981km 137560.016Hz   3mHz=20 -47.5dBOp  96% 17.9dB
2013-10-18 01:49:23 = DK7FC  =20 5981km 137560.016Hz   3mHz -46.4dBOp  = 80% 16.8dB
John, W1TAG

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