Return-Path: Received: from mtain-dh11.r1000.mx.aol.com (mtain-dh11.r1000.mx.aol.com [172.29.65.31]) by air-me10.mail.aol.com (v129.4) with ESMTP id MAILINME104-8bc84d4b00c32cf; Thu, 03 Feb 2011 14:23:47 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dh11.r1000.mx.aol.com (Internet Inbound) with ESMTP id 7EB2C38000288; Thu, 3 Feb 2011 14:23:40 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Pl4l4-0000hV-M9 for rs_out_1@blacksheep.org; Thu, 03 Feb 2011 19:22:22 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Pl4l4-0000hM-1g for rsgb_lf_group@blacksheep.org; Thu, 03 Feb 2011 19:22:22 +0000 Received: from nm11-vm0.bullet.mail.ukl.yahoo.com ([217.146.183.244]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1Pl4l3-0000Hd-Co for rsgb_lf_group@blacksheep.org; Thu, 03 Feb 2011 19:22:22 +0000 Received: from [217.146.183.182] by nm11.bullet.mail.ukl.yahoo.com with NNFMP; 03 Feb 2011 19:22:15 -0000 Received: from [217.146.183.166] by tm13.bullet.mail.ukl.yahoo.com with NNFMP; 03 Feb 2011 19:22:15 -0000 Received: from [127.0.0.1] by omp1007.mail.ukl.yahoo.com with NNFMP; 03 Feb 2011 19:22:15 -0000 X-Yahoo-Newman-Id: 517833.90212.bm@omp1007.mail.ukl.yahoo.com Received: (qmail 36498 invoked from network); 3 Feb 2011 19:22:15 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btopenworld.com; h=DKIM-Signature:Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:In-Reply-To:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=ZrlhFFFmZD289Kr6oXjecBO5HEGswyYlFYOZVHNGRhCDjXig0ZOWPnOr0d0BUSchoYgzoz4VbD5/M4PnJpnJrcWjbz/PykLf8eyCBbWNE+blzxRuL1IZjHKSdxIndKRR/qxLd3L+Fr6pZ9SbZ61lynj3pTYzoGpdhb+wGDy9ryk= ; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btopenworld.com; s=s1024; t=1296760935; bh=1XE43rBROf7ACBTU/6lNZt3sNmFjiHXideF/j5aPHyI=; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:In-Reply-To:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=wbZN606dVKi16OFCszNt8yJ7sMVWeLnQ0kMpz+kBSYhLrRiCTTZj9914RbPsK0+jBa9NFN/H6n9IWxxCbyhLv907+Wv6ysuuaNlMF6q+cxgL2TXVz2CIAKfzSFn2hHWMqtUWyslLhStC9dcdnex0mjLmhC27FQP4+1xSpOUaivM= Received: from JimPC (james.moritz@109.158.236.95 with login) by smtp817.mail.ukl.yahoo.com with SMTP; 03 Feb 2011 19:22:12 +0000 GMT X-Yahoo-SMTP: Cxhli3eswBD1ozmtAojhjrja86kWx0Qm9tycD5QR1DKWrOLgjJcXkw-- X-YMail-OSG: AQqlxZ0VM1mPUXlHMwcUVIzWFbMmpXM6v2iFVZi8HNLsoBM yCsuwK7zrBVOd9W77deXR6qa4u620D4.pMUZ7SjnsvxWR.C.g1fNn3ZL_AfC 9.NhMEch7ot4AMyfJ3nTkH98nsnzLnznr7sVtkJUnjBr3sDP8n.FhqiMo3R1 KxY0LUMJwejWO4mZof40pwx_ZFzMFgbJJRZ2xkxZaTyEv6fYWx3NLM7m_.de IKFStNXOoGfVp661XEgpDM6LOS8QE6Bvh0Dyo X-Yahoo-Newman-Property: ymail-3 Message-ID: From: "James Moritz" To: References: In-Reply-To: Date: Thu, 3 Feb 2011 19:22:15 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6002.18197 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6002.18263 DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,UNPARSEABLE_RELAY=0.001 Subject: LF: Re: Earth-mode or not earth-mode Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.1 required=5.0 tests=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 x-aol-sid: 3039ac1d411f4d4b00bb1860 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Dear Roger, LF Group, Somewhere, G6ALB is applying some AC voltage to some conductor, and some AC current is flowing as a result, down some collection of cables and pipes. At your receiving site, there is presumably some nearby conductor, maybe on of the original ones, maybe a different one, in which some small fraction of G6ALB's current is flowing. This conductor will have some impedance level associated with it, so there will be some AC voltage present on the conductor too. The current will produce some AC magnetic field in the vicinity of the conductor, and the voltage difference between the conductor and surroundings will result in some AC electric field - you can't have one without the other. Some currents will also be conducted/induced in the ground, which has some conductivity, and in other conductors in the vicinity, so there will also be some distribution of currents, electric and magnetic fields associated with these. I have used the word "some" a lot, because all these things, although they surely exist, are rather indefinite in their actual nature, so it is hard to know which are significant and which not. It appears your receiver can detect the electric field produced by G6ALB's signal which is somehow reaching you, but the magnetic field is hard to detect. Why this is so is unclear from the description you have given - it may be because the mode of propagation favours the E-field, or it may be that local noise sources have a stronger H field component. To do so directly, you could calibrate the antennas, but this is quite a lot of work. The experiment Stefan descibes, comparing G6ALB's signal with the relatively well-defined Alpha beacon signal, would be another way to shed light on this. E.g., if G6ALB was down 20dB on the Alpha signal on the E field antenna, but 40dB down on the loop, then it would indicate a 10x higher E/H ratio than for "normal" far-field propagation, and a predominantly high-impedance, "voltage" kind of propagation for G6ALB. It is impossible to say what the non-result for the earth electrode antenna means; I would guess such an antenna would respond to E, H and J to some degree, but without any detection of a signal there is no basis for comparison. Another experiment that would be useful to do would be to track down exactly what utilities the signal was being propagated along. You could use your receiver and antennas /P in a "cable tracker" mode. You would then have an idea whether the E-field was generally favoured, or whether this was peculiar to your QTH. Cheers, Jim Moritz 73 de M0BMU