Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id x5PIkR3w002215 for ; Tue, 25 Jun 2019 20:46:28 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1hfqFl-0004s1-FY for rs_out_1@blacksheep.org; Tue, 25 Jun 2019 19:33:13 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1hfqFi-0004rq-29 for rsgb_lf_group@blacksheep.org; Tue, 25 Jun 2019 19:33:10 +0100 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92) (envelope-from ) id 1hfqFg-0000XQ-Dm for rsgb_lf_group@blacksheep.org; Tue, 25 Jun 2019 19:33:08 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout01.posteo.de (Postfix) with ESMTPS id 7390816005E for ; Tue, 25 Jun 2019 20:33:06 +0200 (CEST) X-DKIM-Result: Domain=posteo.de Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.de; s=2017; t=1561487586; bh=Ubt3cWQuHixOan/cUobaWJPGmPWQX1CVH29fQ/iF2E0=; h=Date:From:To:Subject:From; b=mVkoOVd/Z/JpmN8cV/bFfrALA+9BnWzz/toFUvd3NFG+B8dKUil07x/Oijc4s5e4f bLpftNZNOnftPMyzkpS1maDG1ArU7YIAOWfbcZaP20as3AEcGzqfpNinoRqvgVgil2 YPZTMWVGOwp4ryp4svGkUHeKcj7hbxnaoGlNltHLFMqj3y+f/dsn0P+3a7vSL/CHeT Eyz1Ir47LKvXlfCUNaUWByNgumUsgAdicQqqFz5F2sF6qnV1ljStWyBD+eZkvwIdq1 +yV9plKfGMjuCyQz3sTLQGOX5oY7j5ihc8NF6GeiPHCmH9tYoHQsXF8BkGE8S3340l p8+iUOinbNLbA== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 45YFCP4zjkz6tmG for ; Tue, 25 Jun 2019 20:33:05 +0200 (CEST) Message-ID: <5D1268E1.9020500@posteo.de> Date: Tue, 25 Jun 2019 20:33:05 +0200 From: DK7FC 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: <9ec649ed-7852-89b8-cb0e-d646de9538a9@rtv5.cz> <5D124169.1080309@posteo.de> In-Reply-To: <5D124169.1080309@posteo.de> X-Spam-Score: -2.5 (--) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: Hi all, Today, some 20 minute long carrier transmissions were drone from JN39WI again. The main intention was to calibrate my local RDF spectrogram (still to be done) in the range below 16.4 kHz (JXN) and abo [...] Content analysis details: (-2.5 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [185.67.36.65 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.0 DKIMWL_WL_MED DKIMwl.org - Whitelisted Medium sender X-Scan-Signature: 3b8620872b19e25fb6f4dfaf1256edc3 Subject: ULF/VLF: amateur stair case / carrier transmissions Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=none 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 Hi all, Today, some 20 minute long carrier transmissions were drone from JN39WI again. The main intention was to calibrate my local RDF spectrogram (still to be done) in the range below 16.4 kHz (JXN) and above 82 Hz (ZEVS). So that was a amateur radio ULF/VLF staircase somehow, despite the weak signal strength relative to commercial transmitters. It was a hot day! Far > 30 C here. I started early in the morning and enjoyed the fresh air in the forest. The DC resistance of the 1130m ground loop increased to 73.2 Ohm (measured at 1 A) due to the dry soil. It confirms the dependency shown in the last year! In 2018 i saw the resistance rising up to 94 Ohm in late October, then it dropped to 57 Ohm (-40 %) in just 2 months. It was interesting to see that the antenna current is much higher at lower frequencies (always at resonance | the PA output voltage is nearly constant). This effect was very clearly expressed. IF of interest for other stations (having a data storage): Frequency/Hz Start time/UTC Antenna current/A 970.005 2019-06-25_08:36:20,+20m 2.26 2970.005 2019-06-25_08:13:30,+20m 2.19 5170.005 2019-06-25_07:51:00,+20m 2.09 8270.005 2019-06-25_07:23:00,+25m 1.85 end of the official part. BTW, since a few days, the VLF RX site at DL0AO has a 3 axis VLF receiver recording data from a Octo-soundcard and a Raspberry pi 3, saving data to a 4 TB HDD so there is one more station that won't miss anything from now on (for example unannounced transmissions by SAQ). Some spectrograms may be shown later. Evetually there was a problem with the sample rate correction due to the upheating car, which caused a high deviation of the tracked sample rate. The max allowed range of 10 ppm was left in the end of the experiment but this was noticed a bit late, maybe. 73, Stefan