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 w0PJ8lIn005369 for ; Thu, 25 Jan 2018 20:08:48 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eemox-0005oq-P1 for rs_out_1@blacksheep.org; Thu, 25 Jan 2018 19:04:23 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eemox-0005oe-0B for rsgb_lf_group@blacksheep.org; Thu, 25 Jan 2018 19:04:23 +0000 Received: from mx-out.tlen.pl ([193.222.135.142]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1eemot-0003YD-Ff for rsgb_lf_group@blacksheep.org; Thu, 25 Jan 2018 19:04:21 +0000 Received: (wp-smtpd smtp.tlen.pl 15076 invoked from network); 25 Jan 2018 20:04:18 +0100 Received: from user-94-254-147-91.play-internet.pl (HELO LAPTOPCAAOTGEB) (bxi@go2.pl@[94.254.147.91]) (envelope-sender ) by smtp.tlen.pl (WP-SMTPD) with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP for ; 25 Jan 2018 20:04:18 +0100 From: "Marcin" To: References: <001a01d394ff$8f3f54a0$adbdfde0$@go2.pl> In-Reply-To: Date: Thu, 25 Jan 2018 20:04:17 +0100 Message-ID: <00c801d3960f$4ce1ab10$e6a50130$@go2.pl> MIME-Version: 1.0 X-Mailer: Microsoft Outlook 16.0 Thread-Index: AQH44IVbJHsAHRd/9ntJFuUwdlcFrQFfn/XdAiTQQ+qjHXnbgA== Content-Language: pl X-WP-MailID: c3bd6a03a2dbc864e310b67f628ac4a8 X-WP-AV: skaner antywirusowy Poczty o2 X-WP-SPAM: NO 0000002 [MTFG] 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: 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’d have to head 700 km to the south to do it. The other 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 issues with the electrical equipment and various sensors placed within the railway 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. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: 6d05203b0dc31085ea7fa8b214773e41 Subject: RE: LF: RE: 136kHz WSPR experiment Content-Type: multipart/alternative; boundary="----=_NextPart_000_00C9_01D39617.AEA88410" 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=HTML_60_70,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 This is a multipart message in MIME format. ------=_NextPart_000_00C9_01D39617.AEA88410 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hello Roger, =20 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 = other 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 issues with the electrical equipment and various = sensors placed within the railway 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.=20 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 =20 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 =20 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 in my experience. =20 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! =20 73s Roger G3XBM =20 On 24 January 2018 at 10:38, Marcin < bxi@go2.pl> = wrote: Hello Roger, =20 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-ant= eny-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 =20 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 =20 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. =20 Conclusions? The earth-electrode "antenna" in the ground is quite = effective at 136kHz, but more directional. =20 Next season I will definitely try an , E-field probe on RX! =20 No great DX, but experimentation! =20 73s Roger G3XBM =20 ------=_NextPart_000_00C9_01D39617.AEA88410 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable

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 other 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 issues = with the electrical equipment and various sensors placed within the = railway 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 in 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 <bxi@go2.pl> = 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-ele= mentem-anteny-czyli-eksperymentow-z-dipolami-ziemnymi-ciag-dalszy/#more-7= 20

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

 

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