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[195.171.43.25]) by mx.google.com with ESMTP id xn13si9188812wib.13.2014.06.25.15.20.57 for ; Wed, 25 Jun 2014 15:20:58 -0700 (PDT) Received-SPF: none (google.com: owner-rsgb_lf_group@blacksheep.org does not designate permitted sender hosts) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: owner-rsgb_lf_group@blacksheep.org does not designate permitted sender hosts) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass header.i=@mx.aol.com; dmarc=pass (p=REJECT dis=NONE) header.from=aol.com Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1WzvUa-00087x-HQ for rs_out_1@blacksheep.org; Wed, 25 Jun 2014 23:16:36 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1WzvUa-00087o-7X for rsgb_lf_group@blacksheep.org; Wed, 25 Jun 2014 23:16:36 +0100 Received: from omr-d02.mx.aol.com ([205.188.109.194]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.82) (envelope-from ) id 1WzvUY-0001Rn-Aq for rsgb_lf_group@blacksheep.org; Wed, 25 Jun 2014 23:16:35 +0100 Received: from mtaout-mce01.mx.aol.com (mtaout-mce01.mx.aol.com [172.29.27.205]) by omr-d02.mx.aol.com (Outbound Mail Relay) with ESMTP id 41A76700000B7 for ; Wed, 25 Jun 2014 18:16:32 -0400 (EDT) Received: from White (95-91-237-52-dynip.superkabel.de [95.91.237.52]) by mtaout-mce01.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id 64D0138000081 for ; Wed, 25 Jun 2014 18:16:26 -0400 (EDT) Message-ID: <9DA98BA70F2D476283EB3B4894AD287B@White> From: "Markus Vester" To: References: <53A97738.2070501@gmail.com> <8D15DE5531A8822-27BC-8EBC@webmail-m293.sysops.aol.com> <53AB3B02.2010102@gmail.com> Date: Thu, 26 Jun 2014 00:16:28 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 12.0.1606 X-MimeOLE: Produced By Microsoft MimeOLE V12.0.1606 x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1403734592; bh=+JLxMVo4apCdOpeT5CtwbW2lTCPqFHAFZr7LiGWRYok=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=JHK+CD7bg7KiDtzLskVieFYtFgoF+S1KChdyn/pgEvYtdWcPTJ9fkHzkyCmhX0SwX BpDyRcQBjY86wJLimMw4DXWc1RtcC1DzFqVSVPZTGZXj+Cw9KLzXbn+SlN27p6ZeYp OufIoZv8MBpkzztww3WUcz/mImI9nC10aVdFzSmQ= x-aol-sid: 3039ac1d1bcd53ab4a3a0211 X-AOL-IP: 95.91.237.52 X-Spam-Score: 1.0 (+) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Stefan, yes, understood. If you want complete invisibility though, you could actually bury the wire in the ground, without negative effect on the magnetic field. Or cover it with fallen leaves etc. May seem a bit odd to literally put an antenna underground - tried it with a pair of LF receive loopsticks in the garden and it worked quite well. [...] Content analysis details: (1.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [205.188.109.194 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid 1.0 FREEMAIL_REPLY From and body contain different freemails X-Scan-Signature: 4998b3eda037fec4e885bebc9a2db934 Subject: Re: LF: VLF in Canada - earth loop Content-Type: multipart/alternative; boundary="----=_NextPart_000_000A_01CF90D3.DFCE4450" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_40_50,HTML_MESSAGE, MISSING_OUTLOOK_NAME 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 Dies ist eine mehrteilige Nachricht im MIME-Format. ------=_NextPart_000_000A_01CF90D3.DFCE4450 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Stefan, yes, understood. If you want complete invisibility though, you could = actually bury the wire in the ground, without negative effect on the = magnetic field. Or cover it with fallen leaves etc. May seem a bit odd = to literally put an antenna underground - tried it with a pair of LF = receive loopsticks in the garden and it worked quite well. 73, Markus From: DK7FC=20 Sent: Wednesday, June 25, 2014 11:11 PM To: rsgb_lf_group@blacksheep.org=20 Subject: Re: LF: VLF in Canada - earth loop Hi Markus,=20 Right. But 8m gives a secure distance above ground regarding the = visibility of the wire. 2.5m would work as well but then everybody can = see it (easier). And some m above ground allows to use the wire for some = other games, such as a LF dipole (TX!) or a LF 3 Lambda long wire or = what ever :-) 73, Stefan Am 24.06.2014 19:03, schrieb Markus Vester:=20 Stefan, Joe > I think that 8m above ground should be fine for any tests :-) well (apart from practical reasons like people tripping over it), you = might just as well lay the (insulated) wire on the ground. From receive measurements with your earlier and shorter earth antenna, = we deduced a depth of return current of 29 meters at 23.4 kHz, which = would scale to about 48 m at 8.3 kHz. Thus a two kilometer long earth = antenna would have the same radiation resistance (0.35 milliohm) as a 17 = m high top-loaded vertical. But skin depth and efficiency might be = greater for very low ground conductance. Best 73, Markus ... ------=_NextPart_000_000A_01CF90D3.DFCE4450 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
Stefan,
 
yes, understood. If=20 you want complete invisibility though, you could actually bury the wire = in the=20 ground, without negative effect on the magnetic field. Or cover it with = fallen=20 leaves etc. May seem a bit odd to literally put an antenna = underground=20 - tried it with a pair of LF receive loopsticks in the garden = and it=20 worked quite well.
 
73, Markus
 

From: DK7FC
Sent: Wednesday, June 25, 2014 11:11 PM
Subject: Re: LF: VLF in Canada - earth = loop

Hi Markus,

Right. But 8m gives a = secure=20 distance above ground regarding the visibility of the wire. 2.5m would = work as=20 well but then everybody can see it (easier). And some m above ground = allows to=20 use the wire for some other games, such as a LF dipole (TX!) or a LF 3 = Lambda=20 long wire or what ever :-)

73, Stefan

Am 24.06.2014 19:03, = schrieb=20 Markus Vester:=20
Stefan,=20 Joe
 
> I=20 think that 8m above ground should be fine for any tests :-)
well = (apart=20 from practical reasons like people tripping over it), you might just = as well=20 lay the (insulated) wire on the ground.
 
From receive=20 measurements with your earlier and shorter earth antenna, we = deduced a=20 depth of return current of 29 meters at 23.4 kHz, which = would scale to about 48 m at 8.3 kHz. Thus a two = kilometer long=20 earth antenna would have the same radiation resistance (0.35 = milliohm) as a 17 m high top-loaded vertical. But skin depth and=20 efficiency might be greater for very low ground conductance.
 
Best = 73,
Markus
...
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