Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_PASS,SUBJ_ALL_CAPS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id v496FTE8031983 for ; Tue, 9 May 2017 08:15:30 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1d7yM8-0004VM-Ik for rs_out_1@blacksheep.org; Tue, 09 May 2017 07:10:44 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1d7yKt-0004V8-C1 for rsgb_lf_group@blacksheep.org; Tue, 09 May 2017 07:09:27 +0100 Received: from porthos.netcom.co.uk ([217.72.171.73]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1d7yKn-0003aS-Uq for rsgb_lf_group@blacksheep.org; Tue, 09 May 2017 07:09:24 +0100 X-DKIM-Result: Domain=abelian.org Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:To:Subject:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=ENRYWwXX1or9U54voHZnH73tt9S65nkBiZtBu6jYmZ0=; b=06clixgw90zr+cpIxcAnhpiZrQ cPRmCQj/61EZxGbqMn2G9uDNzlXvpLmG7NwwZ9FpezNJnifwjGWK6i5t5EiKyTlUxVyMFGsBOmXQO LXsz719MIs5hmNicVHFMTM/XcEaI8V1kDHbbFEsMhTqOQ92IDO76gcv0KrZ10nGn4qd4=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:43120 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1d7yKm-0002VG-NM for rsgb_lf_group@blacksheep.org; Tue, 09 May 2017 07:09:20 +0100 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id 21AD140028E for ; Tue, 9 May 2017 06:09:20 +0000 (UTC) To: rsgb_lf_group@blacksheep.org References: <15be6ff3416-71b7-20de5@webprd-a30.mail.aol.com> <3f469a46-15c4-97a9-f571-785c13e9ee70@abelian.org> <02e701d2c7d9$b05ea8f0$111bfad0$@comcast.net> <59109710.1000300@posteo.de> From: Paul Nicholson Message-ID: Date: Tue, 9 May 2017 06:09:20 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - porthos.netcom.co.uk X-AntiAbuse: Original Domain - blacksheep.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - abelian.org X-Get-Message-Sender-Via: porthos.netcom.co.uk: authenticated_id: catchall@abelian.org X-Authenticated-Sender: porthos.netcom.co.uk: catchall@abelian.org X-Scan-Signature: 1c38f63d01970a2bf149f660c9cb2a37 Subject: Re: LF: NA VLF Content-Type: text/plain; charset=utf-8; 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 2.75 Status: RO X-Status: X-Keywords: X-UID: 11641 The daytime signal peaks at a different frequency, averaging 8270.00709300 Hz +/- 0.5 uHz between 08:00 and 17:00. I'm also seeing the same shift at Forest, VA. The frequency is now close to the DDS nominal frequency. Perhaps the shack has warmed up to the temperature the OCXO was calibrated at. Here is the daylight signal at Todmorden, plot centered on 8270.007093: http://abelian.org/vlf/tmp/170508f.gif S/N 12.1 dB in 23.148 uHz and I think we're losing a bit of amplitude on a long integration because the energy is not all in one bin due to drift. These frequency shifts could be a problem for EbNaut. It won't work if the frequency shifts by more than a few uHz during a long transmission. The night signal might just about manage 5 chars with rate 1/16 symbols about 22 seconds, if frequency stable. Day might just do 3 chars with 45 second symbols. A little more ERP would help greatly here. Signal is invisible at Forest during daylight path in 12 hour integration. Today I'll try to optimise beam heading and blanker settings and plot some nice spectra. > Good to learn that I put the decimal point in the right place > for the ERP! I wouldn't take these measurements too seriously. The agreement between LWPC and measured flux is mostly luck. We can say that signal strengths are consistent with your 10uW ERP estimate - we are in the same ball park. I'm happy with the arithmetic - no anomalies. I've added a couple of entries to http://abelian.org/vlf/amateur-radio/ Seems I have to update this file almost daily at the moment. VLF is certainly an interesting band to work with. Everywhere you turn there's something new to try. -- Paul Nicholson --