Return-Path: X-Spam-DCC: paranoid 1290; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, RATWARE_GECKO_BUILD,SPF_PASS autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id u41CxvMr011533 for ; Sun, 1 May 2016 14:59:57 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1awquh-0000cq-Qb for rs_out_1@blacksheep.org; Sun, 01 May 2016 13:55:55 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1awquh-0000ch-4C for rsgb_lf_group@blacksheep.org; Sun, 01 May 2016 13:55:55 +0100 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1awquf-0005Dr-Ih for rsgb_lf_group@blacksheep.org; Sun, 01 May 2016 13:55:54 +0100 Received: from dovecot03.posteo.de (dovecot03.posteo.de [172.16.0.13]) by mout01.posteo.de (Postfix) with ESMTPS id 049BF20AC6 for ; Sun, 1 May 2016 14:55:49 +0200 (CEST) Received: from mail.posteo.de (localhost [127.0.0.1]) by dovecot03.posteo.de (Postfix) with ESMTPSA id 3qyS915bl4z5vMp for ; Sun, 1 May 2016 14:55:49 +0200 (CEST) Message-ID: <5725FCD5.40606@posteo.de> Date: Sun, 01 May 2016 14:55:49 +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: <1545cc43544-7b51-40b@webprd-a09.mail.aol.com> <57222E30.1080202@posteo.de> <57225653.3090907@abelian.org> In-Reply-To: <57225653.3090907@abelian.org> X-Scan-Signature: f38d515a9cad1e977fcfe251941a8120 Subject: ULF: EbNaut transmissions on lower frequencies? 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 2.56 on 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 7962 Hi ULF, Am 28.04.2016 20:28, schrieb Paul Nicholson: > Stefan, want to try EbNaut at a lower frequency? That would > be a good challenge. 6kHz perhaps? Paul, maybe you are right! We don't know so much about the propagation and phase stability on lower frequencies. If we assume the phase is much more stable on lower frequencies then 8.27 kHz, then it may be worth to experiment there, in slower modes. The most important system is, in my opinion, that stable transmissions can be done at any time! I sent 45 characters to you over 850km distance within 24 hours. 24 hours is nothing! It could have been 4 days, no problem! I still have 2 yoghurt cups ready to be added to the coil, no problem to go down another kHz. And i've ordered these 100x 3C85 cores! I'm really looking forward to experiment with them. With these cores it will be no problem to go down to 4 kHz. The question is which antenna current i can get with them. Maybe even 3 kHz is possible. Oh yes, let us try 2.97 kHz, OK? That's ULF! Sounds not realistic? A dream into a dream, you know?! 2.97 kHz, that's a distance of just 1.7 lambda to DF6NM and 8.8 lambda to Paul... My antenna has 114 kOhm reactance there, so 150 mA is no problem. That's about -5 dB over the current current. The radiation resistance falls by another 9 dB. So the signal will be 14 dB weaker? Sounds managable. Sferics are weaker below 5 kHz or so. Is it just due to propagation and will a amateur radiated signal over < 1000 km suffer from the same loss in propagation so the SNR stays the same, apart from the weaker signal? 73, Stefan