Return-Path: Received: from mtain-dg04.r1000.mx.aol.com (mtain-dg04.r1000.mx.aol.com [172.29.65.12]) by air-de03.mail.aol.com (v129.4) with ESMTP id MAILINDE034-5ead4d4af0272bb; Thu, 03 Feb 2011 13:12:55 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dg04.r1000.mx.aol.com (Internet Inbound) with ESMTP id AA53C380000A3; Thu, 3 Feb 2011 13:12:53 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Pl3f5-0000O0-UW for rs_out_1@blacksheep.org; Thu, 03 Feb 2011 18:12:07 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Pl3f5-0000Nr-C6 for rsgb_lf_group@blacksheep.org; Thu, 03 Feb 2011 18:12:07 +0000 Received: from out1.ip05ir2.opaltelecom.net ([62.24.128.241]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Pl3f3-0008AI-9K for rsgb_lf_group@blacksheep.org; Thu, 03 Feb 2011 18:12:07 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Ar4BAIJ+Sk1cEYfn/2dsb2JhbACSZoNijmVzvVaFWASBYI1N X-IronPort-AV: E=Sophos;i="4.60,421,1291593600"; d="scan'208,217";a="331240388" Received: from unknown (HELO xphd97xgq27nyf) ([92.17.135.231]) by out1.ip05ir2.opaltelecom.net with SMTP; 03 Feb 2011 18:11:58 +0000 Message-ID: <005b01cbc3cd$d8dd12b0$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <0DF35BB8-9FC4-4A05-A9B9-675D74FEE669@gmail.com> <4D4ABE55.4060101@iup.uni-heidelberg.de> Date: Thu, 3 Feb 2011 18:11:57 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: RE: More earth-mode tests and a puzzle Content-Type: multipart/alternative; boundary="----=_NextPart_000_0058_01CBC3CD.D890C770" 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=HTML_MESSAGE 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 x-aol-global-disposition: G x-aol-sid: 3039ac1d410c4d4af02466d3 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_0058_01CBC3CD.D890C770 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable The same advice as from others go into the open countryside away from= all pipes and cables and do the job properly. Set up a transmitter as Stefan does out in the forest and then try an= earth mode antenna and RX at intervals and see how you get on. de g3kev ----- Original Message -----=20 From: Stefan Sch=E4fer=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Thursday, February 03, 2011 2:40 PM Subject: Re: LF: RE: More earth-mode tests and a puzzle Hi Roger, First, congrats to the 3 km in QRSS-3! This allows you to do local= QSOs :-) What about G6ALB? Has he tried to receive your transmissions= as well? This would allow you both to to a QRSS-3 VLF QSO!! Have you= tried this? Am 03.02.2011 11:35, schrieb Roger Lapthorn:=20 What I do NOT understand is why I get ZERO signal pick-up from G6A= LB at 3km with another earth-electrode set-up at the RX end. One of my= ground points is the copper central heating radiator which connects= directly to metal pipes in the road. I know this as I use the same se= t-up to launch my own earth-mode signals that can be detected in the= roads with a loop out in the fens >5km away. ...but in your own experiments you received your signal with the loo= p and here you want to receive it with the earth electrodes. This seem= s to show that it is easier possible to receive the magnetic field cau= sed by the current flow in the pipes than measuring a current flow thr= ough the soil between your electrodes in your garden (causing a potent= ial difference between them). Logic tells me that if Andrew G6ALB is launching his signal along= pipes from his earth electrode pair then I would get strongest signal= s by also connecting one ground to the metal pipework at the RX end,= but this is definitely not the case as there is absolutely no signal= detectable in QRSS3 by this method, but at least 20dB S/N with the EF= P! Can someone explain what is going on please as I am very baffled! Check if there is a difference in the signal level and SNR if you= disconnect the EFP from the local ground, i.e. use a battery and a no= tebook. Go out in the fields with all 3 forms of antennas (loop, EFP,= earth electrodes) to check the difference at an equal distance. If th= e noise and a reference signal (e.g. Alphas) stays at the same level= but your 9 kHz signal level is strongly reduced, it may have been sup= ported by the quasi galvanic coupling to one of the TX antennas legs.= This may be the difference compared to your own transmission. As you'= ve been /p with your RX, there was no ground connection to the TX! Go out in the forest, far away from pipes and cables and install a= large (real) earth antenna, pointing to G6ALB. First you may try to= receive G6ALB with the EFP and/or the loop. Good luck and fun with your experiments! 73,Stefan/DK7FC PS: Which of the 3 antennas gives you the best SNR of the Alphas? Wh= ich one shows the sferics as the dominant noise source arround 9 kHz?= :-) What about mains hum? Will you try to receive me this weekend? :-= ) Most probably i'll do the 10th this sunday! ------=_NextPart_000_0058_01CBC3CD.D890C770 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
The same advice as from others go into the ope= n=20 countryside away from all pipes and cables and do the job properly.
Set up a transmitter as Stefan does out in the= forest and=20 then try an earth mode antenna and RX at intervals and see how you get= =20 on.
de g3kev
 
----- Original Message -----
Sent: Thursday, February 03,= 2011 2:40=20 PM
Subject: Re: LF: RE: More ear= th-mode=20 tests and a puzzle

Hi Roger,

First, congrats to the 3 km in QRSS-= 3! This=20 allows you to do local QSOs :-) What about G6ALB? Has he tried to re= ceive your=20 transmissions as well? This would allow you both to to a QRSS-3 VLF= QSO!! Have=20 you tried this?

Am 03.02.2011 11:35, schrieb Roger Lapthorn:= =20

What I do NOT understand is= why I get ZERO signal pick-up=20 from G6ALB at 3km with another earth-electrode set-up at the RX en= d. One of=20 my ground points is the copper central heating radiator which conn= ects=20 directly to metal pipes in the road. I know this as I use the same= set-up to=20 launch my own earth-mode signals that can be detected in the roads= with a=20 loop out in the fens >5km away.
...but in your own= experiments=20 you received your signal with the loop and here you want to receive= it with=20 the earth electrodes. This seems to show that it is easier possible= to receive=20 the magnetic field caused by the current flow in the pipes than meas= uring a=20 current flow through the soil between your electrodes in your garden= (causing=20 a potential difference between them).
Logic tells me that if Andrew G6= ALB is launching his signal=20 along pipes from his earth electrode pair then I would get stronge= st signals=20 by also connecting one ground to the metal pipework at the RX end,= but this=20 is definitely not the case as there is absolutely no signal= =20 detectable in QRSS3 by this method, but at least 20dB S/N with the= EFP! Can=20 someone explain what is going on please as I am very=20 baffled!
Check if there is a difference in the signa= l level=20 and SNR if  you disconnect the EFP from the local ground, i.e.= use a=20 battery and a notebook. Go out in the fields with all 3 forms of ant= ennas=20 (loop, EFP, earth electrodes) to check the difference at an equal di= stance. If=20 the noise and a reference signal (e.g. Alphas) stays at the same lev= el but=20 your 9 kHz signal level is strongly reduced, it may have been suppor= ted by the=20 quasi galvanic coupling to one of the TX antennas legs. This may be= the=20 difference compared to your own transmission. As you've been /p with= your RX,=20 there was no ground connection to the TX!

Go out in the fores= t, far=20 away from pipes and cables and install a large (real) earth antenna,= pointing=20 to G6ALB. First you may try to receive G6ALB with the EFP and/or the= =20 loop.

Good luck and fun with your=20 experiments!

73,Stefan/DK7FC

PS: Which of the 3 antenn= as gives=20 you the best SNR of the Alphas? Which one shows the sferics as the= dominant=20 noise source arround 9 kHz? :-) What about mains hum? Will you try= to receive=20 me this weekend? :-) Most probably i'll do the 10th this=20 sunday!
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