Return-Path: X-Spam-DCC: paranoid 1181; 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=-2.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, 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 u2HIv7Ia025118 for ; Thu, 17 Mar 2016 19:57:07 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1agcyX-0006HP-Uf for rs_out_1@blacksheep.org; Thu, 17 Mar 2016 18:48:49 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1agcyX-0006HG-J3 for rsgb_lf_group@blacksheep.org; Thu, 17 Mar 2016 18:48:49 +0000 Received: from smtpout1.wanadoo.co.uk ([80.12.242.29] helo=smtpout.wanadoo.co.uk) by relay1.thorcom.net with esmtp (Exim 4.86) (envelope-from ) id 1agcyV-0000jZ-RQ for rsgb_lf_group@blacksheep.org; Thu, 17 Mar 2016 18:48:48 +0000 Received: from AGB ([95.150.81.153]) by mwinf5d06 with ME id X6oi1s0033JUcvz036oiJf; Thu, 17 Mar 2016 19:48:46 +0100 X-ME-Helo: AGB X-ME-Date: Thu, 17 Mar 2016 19:48:46 +0100 X-ME-IP: 95.150.81.153 Message-ID: From: "Graham" To: References: <56E526C8.5010401@abelian.org> <1536f9e8813-7821-7aea@webprd-m99.mail.aol.com> <56E5DCEF.4050905@abelian.org> <56E7090D.4090601@tiscali.co.uk> <56E7122E.1090907@abelian.org> <016f01d17e34$65318b80$2f94a280$@comcast.net> <56EAF20F.7050008@abelian.org> In-Reply-To: <56EAF20F.7050008@abelian.org> Date: Thu, 17 Mar 2016 18:48:41 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 X-Scan-Signature: d7fcd9b75df8d1b09ddef9df028bd9ae Subject: Re: LF: EbNaut from Todmorden Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response 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: 7392 I've a vague recollection that someone on the list said that you don't need an NoV for an earth antenna? Can anyone recall? Yes its Audio and not covered by the electro magnetic regulations 73-G, -------------------------------------------------- From: "Paul Nicholson" Sent: Thursday, March 17, 2016 6:06 PM To: Subject: Re: LF: EbNaut from Todmorden > > I tried the long wire at ELF - it was useless. No Schumann and > it can't see transients from TLEs. In fact it was pretty poor > at VLF which probably shows how well it couples to the trees. > So, not a very good antenna. > > I took it down. > > I spotted a place where I could probably put up 200m of wire > at about 8 metres, clear of any trees. It's further from > the house though so would need a long coax to reach. I can > borrow some scaffold poles from a neighbour. Not too far from > a muddy spring (we have plenty of those) for a good RF ground. > I'll need to buy some coax and some proper antenna wire. > > Stefan wrote (a week ago): > > > A T200-2 can be used for 1 kW ... > > A couple of those will arrive this week. > > Also was inspired by something that Andy posted recently > about PAs powered from rectified mains. Somewhere in the shed > there's a mains isolating transformer and a nice variac. > > I've a vague recollection that someone on the list said that > you don't need an NoV for an earth antenna? Can anyone recall? > > I could run a wire for a km across the moors and terminate it > in a bog. There's an industrial audio amplifier in the shed > which is good for 4kW. Such a long earth loop would need > quite a high driving voltage. Also in the shed is a big toroidal > transformer, about 20cm diameter by 10cm thick, which might > make a hefty audio transformer if the material is up to it. > > ... > > I dug the big toroid out. It has two windings, 400 turns > giving 0.98H and 10 turns of 2cm wide copper strip for 395 uH. > So about 6.17uH/turns^2. At 8270Hz 2.44V in gives 101.6V out. > The amplifier is too heavy for one person to lift so I can't > try it into the xfmr until an unsuspecting friend comes to visit. > > -- > Paul Nicholson > -- >