Return-Path: X-Spam-DCC: paranoid 1181; Body=3 Fuz1=3 Fuz2=3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,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 u2CHJqXT011541 for ; Sat, 12 Mar 2016 18:19:52 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1aen8o-0006yk-Cj for rs_out_1@blacksheep.org; Sat, 12 Mar 2016 17:15:50 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1aen8o-0006yb-1c for rsgb_lf_group@blacksheep.org; Sat, 12 Mar 2016 17:15:50 +0000 Received: from parrot.netcom.co.uk ([217.72.171.49]) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1aen8m-0007X0-C4 for rsgb_lf_group@blacksheep.org; Sat, 12 Mar 2016 17:15:48 +0000 Received: from sb.abelian.org (i-194-106-52-83.freedom2surf.net [194.106.52.83]) by parrot.netcom.co.uk (Postfix) with ESMTP id 49AE53273EB for ; Sat, 12 Mar 2016 17:15:43 +0000 (GMT) Received: from [127.0.0.1] (localhost [127.0.0.1]) by sb.abelian.org (Postfix) with ESMTP id 36CC528A0135 for ; Sat, 12 Mar 2016 17:15:47 +0000 (UTC) Message-ID: <56E44EC3.8050404@abelian.org> Date: Sat, 12 Mar 2016 17:15:47 +0000 From: Paul Nicholson User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <56DEAE40.8000809@tiscali.co.uk> <56DEF9AE.7060203@posteo.de> <56E1F553.1080306@abelian.org> <56E1FC61.8090400@posteo.de> <56E34476.4060707@gmx.net> <56E3C9CC.1030704@abelian.org> <56E43F1E.2020400@posteo.de> In-Reply-To: <56E43F1E.2020400@posteo.de> X-Scan-Signature: f38d515a9cad1e977fcfe251941a8120 Subject: Re: LF: EbNaut from Todmorden Content-Type: text/plain; charset=ISO-8859-1; 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: 7310 > 15:15 UTC on 136.175 kHz, i bet this was your signal! ;-) Could be? Carrier on air 136.175 kHz intermittent since 16:40, continuous since 16:54 and later will move to a frequency in the OPDS band for some EbNaut. 236W DC input. Instant LF coupling transformer: rummage in the shed until you find a 50 metre coil of 3-core heavy duty mains cable. Diameter about 40cm, turns 40. Each wire measures 630uH with the other wires open circuit. With one wire shorted, the other wires measure 45uH each. I think that's not bad and the leakage inductance is half of what I need to tune the antenna anyway. I just needed a small extra coil to bring it into tune. Found a small coil of heavy loudspeaker cable - about the right inductance, wired it in series and bingo! Tunes 136 very nicely. So, I didn't actually have to wind anything in the end. Near the end of the coax a stream emerges from the ground in a muddy patch. I pushed some scrap copper pipes into the mud. Three good stakes a few metres apart. Instant ground terminal. I'm getting to like LF - you can take some liberties. Coils of mains cable as transformers, terminal blocks as RF connectors, buckets of salty water for dummy loads. -- Paul Nicholson --