Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id w0PJt6Od005506 for ; Thu, 25 Jan 2018 20:55:07 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eenXA-0006Dk-6l for rs_out_1@blacksheep.org; Thu, 25 Jan 2018 19:50:04 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eenX5-0006DW-VH for rsgb_lf_group@blacksheep.org; Thu, 25 Jan 2018 19:49:59 +0000 Received: from mail-ot0-x22c.google.com ([2607:f8b0:4003:c0f::22c]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1eenX2-0003ib-8g for rsgb_lf_group@blacksheep.org; Thu, 25 Jan 2018 19:49:58 +0000 Received: by mail-ot0-x22c.google.com with SMTP id t35so7746947otd.13 for ; Thu, 25 Jan 2018 11:49:55 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=OnkGWPZMeCY40HQPdHtVhArMTLGygCav1mer/2p8KGE=; b=T+Ij6Xy/6yrLyrw4xUEZe+sF9iCn6rIGx+qTB728CMlC76dfFpftSbQVtEDn4gc2mp 2IQZtWdGkwO2SW3jEcShkynTHVnp9ZYhZdlwyTUlsngwHQbe38nai8dO3jUlUv8Y8k6B nAIW1ESxxYz5WLrtb8Ylfwcm2UPzLw4ZtrFp/NhcqqWJO6UYKB0P8WITG8NuY4AqbRuS 1xZlJ/NpQGBDiLiUChh15Sy5EFcpzqS+4G8DCVYzQCFJ8sTQdL7siCFLzJOOGzgUzEwi p+urH0nhX9sIxuz2WrkG+3vObrtGTOcbJldXIJmn0hi/1aX/OscUXzLwoaOEg5D+B0dX rgNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=OnkGWPZMeCY40HQPdHtVhArMTLGygCav1mer/2p8KGE=; b=ugLioQYdRo92eznJ7NVIQ2kxOjXiT862Jx/R73VN6mV9SPC61z316fglVMbItMrfGq C1PueQgH9CzjMShCiFM4QSGYdloCVvPD2CRGts3jZf/TyHv46TtN97zerQzS7KXd5oO3 vC1JzzxCfBWF8qkaRsIim9JiqZqOdNFeArORxEais4Goq4n1rV8rzcVjpFINPa7zn+PZ 22lMMdch2ejKKYlDNU/xFx+WKaiPrm3wmemx8iD4GozAXS0yxz491d4K1WOdAh/sQbwl s+E4S+tC61eu93xeZBX5tU511/oprr0I9Bd4iHlTIkHMm9MvnxNagF++VqWxnIRcmovx f3wg== X-Gm-Message-State: AKwxytf298j7ubodbe28R9k8IzZj6TcotaqYqzB/KtoITXoFIpZ2i/7r qZj1I4YzTZ3ZkI4q7et0e3YJv1BbF2HFwsG8I3CwFg== X-Google-Smtp-Source: AH8x226NYSS2gmNh39xDHH9qVgFQID8c/xEdx4eAOjMKHBdP2IXmGJLxBptsnLipC6HMfxuR4yNJ29brTyI0AeX1VBg= X-Received: by 10.157.94.17 with SMTP id d17mr13463044oti.386.1516909789404; Thu, 25 Jan 2018 11:49:49 -0800 (PST) MIME-Version: 1.0 Received: by 10.157.28.166 with HTTP; Thu, 25 Jan 2018 11:49:48 -0800 (PST) In-Reply-To: <00c801d3960f$4ce1ab10$e6a50130$@go2.pl> References: <001a01d394ff$8f3f54a0$adbdfde0$@go2.pl> <00c801d3960f$4ce1ab10$e6a50130$@go2.pl> From: Roger Lapthorn Date: Thu, 25 Jan 2018 19:49:48 +0000 Message-ID: To: "rsgb_lf_group@blacksheep.org" X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Marcin, I agree the electrode contact should be good (into the ground) but you need the ground *between* the electrodes to have a *low* conductivity. Otherwise the "loop in the ground" is very small. The idea works best when the effective loop area is large in my view. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rogerlapthorn[at]gmail.com) 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: e7c02b6e85723bae4746298f7f529717 Subject: Re: LF: RE: 136kHz WSPR experiment Content-Type: multipart/alternative; boundary="089e082c76dc27631f05639f1554" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,HTML_MESSAGE, TO_ADDRESS_EQ_REAL 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 --089e082c76dc27631f05639f1554 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Marcin, I agree the electrode contact should be good (into the ground) but you need the ground *between* the electrodes to have a *low* conductivity. Otherwise the "loop in the ground" is very small. The idea works best when the effective loop area is large in my view. Mind you, I am not an expert! This is *my* experience and what I say could well be wrong. I have only ever used earth-electrode "antennas" with very short baselines. At the old QTH it was about 20m and at this QTH maybe 10m. In my case, certainly at 136kHz it acts like an H-field antenna. With a long baseline maybe it acts as an E-field antenna? As you can see, I talk a lot of rubbish. I'm good at that, HI. The way to find out is try it and see= . Best of luck! 73s Roger G3XBM On 25 January 2018 at 19:04, Marcin wrote: > Hello Roger, > > > > northern Poland is in majority a land of beautiful plains. Ground waters > can be found already just a dozen centimetres below ground level due to > depression. The conductivity in the ground could be described as good or > even very good. If I wanted to set up an antenna above ground with poor > conductivity I=E2=80=99d have to head 700 km to the south to do it. The o= ther thing > is that it would be very difficult to find a few km wide deserted spot to > hang the antenna. I once tried using a 22 km long narrow gauge railway > (with their consent, of course) track but over 100 year-old rails had > nearly 1kOhm resistance. The electrified railway is a much better fit for > this purpose as there are additional electrical connections between the > rails but connecting additional grounding to those rails would cause issu= es > with the electrical equipment and various sensors placed within the railw= ay > structure. When I did some tests once the DC (stray voltage) was ca. 20A > and the voltage up to 50V. Maybe a tramway track would fit better? > Unfortunately those rails in my town are not well isolated and can be > partially hidden in the ground. > > Ground dipole antennas will work well above the ground with god > conductivity if: > > - their length at least match the length of the wave > - the electrodes have a very good contact with the ground > - the wire which connects the electrodes is carefully isolated from > the ground > > 73! Marcin SQ2BXI > > > > *From:* owner-rsgb_lf_group@blacksheep.0org [mailto:owner-rsgb_lf_group@ > blacksheep.org] *On Behalf Of *Roger Lapthorn > *Sent:* Wednesday, January 24, 2018 3:00 PM > *To:* rsgb_lf_group@blacksheep.org > *Subject:* Re: LF: RE: 136kHz WSPR experiment > > > > To get best results I think you need LOW conductivity around the > earth-electrode "antenna", so the signal spread (and hence effective loop > area) is greatest. Placing near a river is likely to give poor results i= n > my experience. > > > > At 136kHz I suspect the earth-electrode "antenna" can be better than many > solutions in the better directions (end-on), although I very much doubt > that would match a good Marconi with a good ground system. My compromise > vertical is NOT a very good LF/MF antenna! > > > > 73s > > Roger G3XBM > > > > On 24 January 2018 at 10:38, Marcin wrote: > > Hello Roger, > > > > Big earth electrode antenna allows transmitting on 136kHz with average > results. > > https://klubnl.pl/wpr/en/index.php/2018/01/09/most-na- > wisle-elementem-anteny-czyli-eksperymentow-z-dipolami- > ziemnymi-ciag-dalszy/#more-720 > > We are slowly getting ready for testing at 8.27kHz but for this test we > needed 10km of wire=E2=80=A6 > > 73! Marcin SQ2BXI > > > > *From:* owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@ > blacksheep.org] *On Behalf Of *Roger Lapthorn > *Sent:* Wednesday, January 24, 2018 10:20 AM > *To:* rsgb_lf_group@blacksheep.org; rsgb_lf_group@yahoogroups.co.uk > *Subject:* LF: 136kHz WSPR experiment > > > > A couple of Gs came on. *G3XIZ* (46km) was 2-3dB better S/N on the > earth-electrodes than on the compromise vertical. He is end-on to the > "loop" in the ground. *G6AVK* was not copied *at all*. He is orthogonal > to the "loop" in the ground. I was quite surprised not to spot him at all > though. > > > > Conclusions? The earth-electrode "antenna" in the ground is quite > effective at 136kHz, but more directional. > > > > Next season I will definitely try an , E-field probe on RX! > > > > No great DX, but experimentation! > > > > 73s > > Roger G3XBM > > > --089e082c76dc27631f05639f1554 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Marcin,

I agree the elect= rode contact should be good (into the ground) but you need the ground be= tween the electrodes to have a low conductivity. Otherwise the &= quot;loop in the ground" is very small. The idea works best when the e= ffective loop area is large in my view.

Mind you,= I am not an expert! This is my experience and what I say could well= be wrong. I have only ever used earth-electrode "antennas" with = very short baselines. At the old QTH it was about 20m and at this QTH maybe= 10m. In my case, certainly at 136kHz it acts like an H-field antenna. With= a long baseline maybe it acts as an E-field antenna? As you can see, I tal= k a lot of rubbish. I'm good at that, HI. The way to find out is try it= and see.

Best of luck!

7= 3s
Roger G3XBM

On 25 January 2018 at 19:04, Marcin &l= t;bxi@go2.pl>= wrote:

Hello Roger,

=C2=A0

northern Poland is in majority a land of beautiful plains. Groun= d waters can be found already just a dozen centimetres below ground level d= ue to depression. The conductivity in the ground could be described as good= or even very good. If I wanted to set up an antenna above ground with poor= conductivity I=E2=80=99d have to head 700 km to the south to do it. The ot= her thing is that it would be very difficult to find a few km wide deserted= spot to hang the antenna. I once tried using a 22 km long narrow gauge rai= lway (with their consent, of course) track but over 100 year-old rails had = nearly 1kOhm resistance. The electrified railway is a much better fit for t= his purpose as there are additional electrical connections between the rail= s but connecting additional grounding to those rails would cause issues wit= h the electrical equipment and various sensors placed within the railway st= ructure. When I did some tests once the DC (stray voltage) was ca. 20A and = the voltage up to 50V. Maybe a tramway track would fit better? Unfortunatel= y those rails in my town are not well isolated and can be partially hidden = in the ground.

Ground dipole antennas will work well = above the ground with god conductivity if:

  • their l= ength at least match the length of the wave
  • the electrodes have a very good contact with th= e ground
  • the wire = which connects the electrodes is carefully isolated from the ground<= u>

73! Marc= in SQ2BXI

=C2=A0

From: owner-rsgb_lf_group@blacks= heep.0org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of= Roger Lapthorn
Sent: Wednesday, January 24, 2018 3:00 PM
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: RE: 136= kHz WSPR experiment

<= span lang=3D"EN-US">=C2=A0

To get best results I think you need LOW cond= uctivity around the earth-electrode "antenna", so the signal spre= ad (and hence effective loop area) is greatest.=C2=A0 Placing near a river = is likely to give poor results in my experience.

=C2=A0

At 136kHz I suspect the earth-electrode "antenna" can= be better than many solutions in the better directions (end-on), although = I very much doubt that would match a good Marconi with a good ground system= . My compromise vertical is NOT a very good LF/MF antenna!

=C2= =A0

73s

Roger G3XBM

= =C2=A0

On= 24 January 2018 at 10:38, Marcin <bxi@go2.pl> wrote:

Hello Roger,

=C2=A0

Big earth electrode antenna allow= s transmitting on 136kHz with average results.

https://klubnl.pl/wpr/en/index.php/2= 018/01/09/most-na-wisle-elementem-anteny-czyli-eksperymentow-z-di= polami-ziemnymi-ciag-dalszy/#more-720<= u>

We are slo= wly getting ready for testing at 8.27kHz but for this test we needed 10km o= f wire=E2=80=A6

73! Marcin SQ2BXI

= =C2=A0

From: owner-rsg= b_lf_group@blacksheep.org [mailto:= owner-rsgb_lf_group@blacksheep.org] On Behalf Of Roger Lapthorn
Sent: Wedne= sday, January 24, 2018 10:20 AM
To: rsgb_lf_gr= oup@blacksheep.org; r= sgb_lf_group@yahoogroups.co.uk
S= ubject: LF: 136kHz WSPR experiment

=C2=A0

A cou= ple of Gs came on. G3XIZ (46km) was 2-3dB better S/N on the earth-el= ectrodes than on the compromise vertical. He is end-on to the "loop&qu= ot; in the ground. G6AVK was not copied at all. He is orthogo= nal to the "loop" in the ground. I was quite surprised not to spo= t him at all though.

=C2=A0

Conclusions? The earth-electrode "antenna" i= n the ground is quite effective at 136kHz, but more directional.

=C2=A0<= span lang=3D"EN-US">

Next season= I will definitely try an , E-field probe on RX!

=C2=A0

No great DX, but experiment= ation!

=C2=A0

73s

Roger G3XBM

=C2=A0


--089e082c76dc27631f05639f1554--