Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_PASS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: : mailn 1480; Body=3 Fuz1=3 Fuz2=3 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 v0MLW1FO005786 for ; Sun, 22 Jan 2017 22:32:03 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1cVPgX-0000Ak-LG for rs_out_1@blacksheep.org; Sun, 22 Jan 2017 21:28:25 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1cVPgX-0000Aa-7M for rsgb_lf_group@blacksheep.org; Sun, 22 Jan 2017 21:28:25 +0000 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 4.87) (envelope-from ) id 1cVPgU-0005WI-NG for rsgb_lf_group@blacksheep.org; Sun, 22 Jan 2017 21:28:24 +0000 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=mmmQe+mBgGsp9bqptZ1GNH8ZLaMHx2IjVE6kknNWjEg=; b=ArpgWd5uJxwJ00miv6xgf98b2o zf5ztjR3vmf+c+6+OKql3brAwGxoKHiUscP+dSie6HJq7r32NCZoRBoHyP341p0f0bxnkEIAWJPhW FG5IUeUS0hR5gdlMg2RNElUh+1e7/c3HKbR5BcznHfk6w164yx2dhKVLQAqzsCBi86s0=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:45738 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1cVPgU-0007RQ-43 for rsgb_lf_group@blacksheep.org; Sun, 22 Jan 2017 21:28:22 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id 700F84004FD for ; Sun, 22 Jan 2017 21:28:21 +0000 (UTC) To: rsgb_lf_group@blacksheep.org References: <159c7eb584f-7414-9709@webprd-a45.mail.aol.com> From: Paul Nicholson Message-ID: <588523F5.2020402@abelian.org> Date: Sun, 22 Jan 2017 21:28:21 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: <159c7eb584f-7414-9709@webprd-a45.mail.aol.com> 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: e09cca6d8e44a91eadbdfb3e1b8aec09 Subject: Re: VLF: EbNaut 8270.1 Hz, carrier 8270.0025 Hz 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: 10300 Markus wrote: > I assume that was obtained by undoing the known keying and then > measuring carrier SNR? Yes, conveniently the Linux version of ebnaut has some options for doing that. It reports the phase too, which I forgot to mention: 21st: -68.4 degrees 22nd: -64.4 degrees Coil Q factors have all sorts of strange variations, especially when they couple to their environment. Q factor can change significantly on a time scale of minutes especially in icy conditions. We would expect Q to rise as temperature falls but sometimes it does the opposite. Several years ago I was involved in some long experiments which automatically measured and logged the Q factor of several resonant modes of Tesla coil solenoids. We recorded a lot of variations which were difficult to explain. -- Paul Nicholson --