Return-Path: Received: (qmail 21172 invoked from network); 20 Apr 2000 10:35:55 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by grants.core.plus.net.uk with SMTP; 20 Apr 2000 10:35:55 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12iEBX-0002CH-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 20 Apr 2000 11:27:47 +0100 Content-Transfer-Encoding: 8bit Received: from bob.dera.gov.uk ([192.5.29.90]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12iEBT-0002CC-00 for rsgb_lf_group@blacksheep.org; Thu, 20 Apr 2000 11:27:44 +0100 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id LAA09080; Thu, 20 Apr 2000 11:30:20 +0100 (BST) X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 25259 invoked from network); 20 Apr 2000 11:24:21 -0000 Received: from gauntlet.mail.dera.gov.uk (172.16.9.10) by baton.dera.gov.uk with SMTP; 20 Apr 2000 11:24:21 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: by gauntlet.mail.dera.gov.uk; id KAA01978; Thu, 20 Apr 2000 10:14:23 GMT Received: from unknown(146.80.11.40) by gauntlet.mail.dera.gov.uk via smap (3.2) id xma001966; Thu, 20 Apr 00 10:14:04 GMT Received: from frn-gold-1.dera.gov.uk (unverified) by mailguard.dera.gov.uk (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Thu, 20 Apr 2000 11:30:53 +0100 Received: by FRN-GOLD-1 with Internet Mail Service (5.0.1460.8) id <2J099AKL>; Thu, 20 Apr 2000 11:25:36 +0100 Message-ID: <3617AC3245C2D1118A840000F805359C01752889@PDW-MERCURY-1> From: "Talbot Andrew" To: "'LF Group'" Subject: LF: LF Dopplergrams Date: Thu, 20 Apr 2000 11:25:34 +0100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.0.1460.8) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Last night I tried to make a Dopplergram trace of a carrier transmitted from Marco in a bandwidth of 0.12 Hz. On looking at the plot this morning I'm not too sure what to make of it an whether the results are even genuine . Firstly, the frequency seems too far out, centred at 0.04 Hz low and there is a wobble on the trace about 0.02 Hz wide which might or might not be propagation effects. Marco has not confirmed what source he was using for the transmission. Although he had said it was going to be a Rubidium source I am surprised the frequency shift is as high as that observed Conventional Dopplergrams on 3.5 MHz typically show a few Hz shift overnight plus a spreading of the signal, so a simple linear scaling would appear to give the right order of frequency shift to that observed. There was not a lot of spreading visible, but that may be consistent with a single reflection from a moving cleaner layer. But I do not know enough about propagation mechanisms to know if simple scaling is appropriate from 3.5 to 0.137 MHz I'll send a copy of the dopplergram / spectrogram plot to anyone wanting it. Another try tonight hopefully. Andy G4JNT@ARRL.NET or DRASSEW2@INTERALPHA.CO.UK over the Easter break. -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.