Return-Path: Received: from mtain-df07.r1000.mx.aol.com (mtain-df07.r1000.mx.aol.com [172.29.64.219]) by air-mb06.mail.aol.com (v129.4) with ESMTP id MAILINMB062-a6ff4d023b131ab; Fri, 10 Dec 2010 09:37:07 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-df07.r1000.mx.aol.com (Internet Inbound) with ESMTP id 79E26380001A7; Fri, 10 Dec 2010 09:37:04 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PR44x-0006dA-0s for rs_out_1@blacksheep.org; Fri, 10 Dec 2010 14:36:11 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PR44w-0006d1-EH for rsgb_lf_group@blacksheep.org; Fri, 10 Dec 2010 14:36:10 +0000 Received: from nm4.bullet.mail.sp2.yahoo.com ([98.139.91.74]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1PR44u-0002kX-TV for rsgb_lf_group@blacksheep.org; Fri, 10 Dec 2010 14:36:10 +0000 Received: from [98.139.91.62] by nm4.bullet.mail.sp2.yahoo.com with NNFMP; 10 Dec 2010 14:36:01 -0000 Received: from [98.139.91.40] by tm2.bullet.mail.sp2.yahoo.com with NNFMP; 10 Dec 2010 14:36:01 -0000 Received: from [127.0.0.1] by omp1040.mail.sp2.yahoo.com with NNFMP; 10 Dec 2010 14:36:01 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 48830.19520.bm@omp1040.mail.sp2.yahoo.com Received: (qmail 96447 invoked by uid 60001); 10 Dec 2010 14:36:00 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1291991760; bh=KmRkE8WyHQYXAVHqDRMLS7GXL86WtAEfyskLhkBSrVM=; h=Message-ID:X-YMail-OSG:Received:X-Mailer:References:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=c/JlwlHDWqdc019RElvXcsXXv285doTG4nDV3AHf4vwKeaqSZspb/Ul91mv7AMq+mApvyYfKYoz1RjMf6df7ysq39/G07+FeYl4i7k4BtovUS/e9k/uDG+7kn7/8HDeod4OVQ6Q5vEu11Vlym5HsTdpZvcgDZH5+fTASincd4FQ= DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:X-YMail-OSG:Received:X-Mailer:References:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=zVLI0zxZke/g5JRtuYRJBKXJrFtd0qpmU1wQiq2CgHLkV7bV96eY9bdOwix/C1f9tBkMB58VSVbCA332LPnZVdFWK3DfNlszNAO8ct3deic/m8gq+8hh2Mvb0N/LYnOdht5KYgB8cG+YmGVPAiv1/Acnz6vhAVr8RzaqMzIzke8=; Message-ID: <733306.95975.qm@web111909.mail.gq1.yahoo.com> X-YMail-OSG: 5UzNpcgVM1nD1qwI8bHA1OWXafscmFrBgYMP_fJdlpBcnCq rT8T7pnLK Received: from [151.99.187.181] by web111909.mail.gq1.yahoo.com via HTTP; Fri, 10 Dec 2010 06:36:00 PST X-Mailer: YahooMailRC/553 YahooMailWebService/0.8.107.285259 References: Date: Fri, 10 Dec 2010 06:36:00 -0800 (PST) From: Daniele Tincani To: rsgb_lf_group@blacksheep.org In-Reply-To: MIME-Version: 1.0 DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: RE: Earth mode tests (8.76kHz) Content-Type: multipart/alternative; boundary="0-897344182-1291991760=:95975" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.4 required=5.0 tests=FORGED_YAHOO_RCVD,HTML_30_40, HTML_FONTCOLOR_BLUE,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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d229.1 ; domain : yahoo.com DKIM : pass x-aol-sid: 3039ac1d40db4d023b105fe1 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --0-897344182-1291991760=:95975 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable I agree. Also consider that even a negative result is a progress, compared= to no=20 results. So good luck and best 73's Daniele ________________________________ From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Sent: Fri, December 10, 2010 3:02:34 PM Subject: LF: RE: Earth mode tests (8.76kHz) >=A0but fun experiments nonetheless=20 =A0 Roger, =A0 that's the spirit, it's a hobby so it should be fun. =A0 Good luck with the VLF experiments. =A0 73, Rik=A0 ON7YD - OR7T =A0 ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g]=20 namens Roger Lapthorn [rogerlapthorn@gmail.com] Verzonden: vrijdag 10 december 2010 14:53 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: Earth mode tests (8.76kHz) Today I did a test receiving my 8.76kHz QRSS3 VLF signal 5.1km away from= the=20 home comparing reception using (a) an 80cm loop antenna and (b) a small ea= rth=20 electrode antenna (14m spacing) using a variety of pre-amps.=A0 Although= quite=20 solid reception (17dB S/N in 0.18Hz BW) was achieved using the loop laying= flat=20 on the ground, there was absolutely nothing detected using the earth elect= rodes=20 which were pushed into the soil either side of the road, which was both=20 surprising and disappointing. I used the very same pre-amp in both cases= and=20 also tried the lo-Z input 8-9kHz tuned pre-amp with the earth electrodes= that=20 successfully copied DK7FC at 648km last weekend on the earth electrodes at= home.=20 Several possibilities for the failure with the earth electrodes at the RX= site:=20 * The electrode spacing was far too small=20 * The barbecue skewers used as RX electrodes were too short and not ma= king=20 decent soil contact=20 * The soil was too wet, so the pick-up (effective loop area in the gro= und) was=20 lower than with dry, low conductivity soil; the test site is in the fens= where=20 the soil is a dark peat. Next step is to repeat the test up on the chalk= uplands=20 to the south of the QTH at about 4km distance where soil conductivity will= be=20 lower and to try a larger earth electrode spacing on receive. When compared with the 2873km DX by Stefan this is nothing to get too exci= ted=20 about, but fun experiments nonetheless. 73s Roger G3XBM --=20 g3xbm-qrp.blogspot.com/ www.g3xbm.co.uk www.youtube.com/user/g3xbm G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088 =20 --0-897344182-1291991760=:95975 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
I agree. Also consider that even a negative result is a progre= ss, compared to no results.
So good luck and best 73's
Daniele
=
From: Rik Strobbe <Rik.= Strobbe@fys.kuleuven.be>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org&g= t;
Sent: Fri, December= 10, 2010 3:02:34 PM
Subject: LF: RE: Earth mode tests (8.76kHz)

> but fun experiments nonetheless
 <= /DIV>
Roger,
 
that's the spirit, it's a hobb= y so it should be fun.
 
Good luck with the VLF experim= ents.
 
73, Rik  ON7YD - OR7T
 
Van: owner-rsgb_lf_gro= up@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Roger Laptho= rn [rogerlapthorn@gmail.com]
Verzonden: vrijdag 10 december 2010= 14:53
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: LF= : Earth mode tests (8.76kHz)

Today I did a test receiving my 8.76kHz QRSS3 VLF signal 5.1km away= from the home comparing reception using (a) an 80cm loop antenna and (b)= a small earth electrode antenna (14m spacing) using a variety of pre-amps= .  Although quite solid reception (17dB S/N in 0.18Hz BW) was achieve= d using the loop laying flat on the ground, there was absolutely nothing= detected using the earth electrodes which were pushed into the soil eithe= r side of the road, which was both surprising and disappointing. I used th= e very same pre-amp in both cases and also tried the lo-Z input 8-9kHz tun= ed pre-amp with the earth electrodes that successfully copied DK7FC at 648= km last weekend on the earth electrodes at home.

Several possibili= ties for the failure with the earth electrodes at the RX site:
  • The electrode spacing was far too small
  • The barbecue skewers used as RX electrodes were too short and not maki= ng decent soil contact
  • The soil was too wet, so the pick-up (effective loop area in the groun= d) was lower than with dry, low conductivity soil; the test site is in the= fens where the soil is a dark peat.
Next step is to repeat the= test up on the chalk uplands to the south of the QTH at about 4km distanc= e where soil conductivity will be lower and to try a larger earth electrod= e spacing on receive.

When compared with the 2873km= DX by Stefan this is nothing to get too excited about, but fun experiment= s nonetheless.

73s
Roger G3XBM

--
g3xbm-q= rp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm<= BR>G3XB= M   GQRP 1678    ISWL G11088
<= br> --0-897344182-1291991760=:95975--