Return-Path: Received: from mtain-dg05.r1000.mx.aol.com (mtain-dg05.r1000.mx.aol.com [172.29.65.13]) by air-da02.mail.aol.com (v129.4) with ESMTP id MAILINDA024-86624c19db46195; Thu, 17 Jun 2010 04:22:30 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dg05.r1000.mx.aol.com (Internet Inbound) with ESMTP id D48173800160B; Thu, 17 Jun 2010 04:22:24 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OPALZ-0007Ko-Pz for rs_out_1@blacksheep.org; Thu, 17 Jun 2010 09:21:13 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OPALZ-0007Kf-4s for rsgb_lf_group@blacksheep.org; Thu, 17 Jun 2010 09:21:13 +0100 Received: from cavuit02.kulnet.kuleuven.be ([134.58.240.44]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OPALU-0000qX-Oo for rsgb_lf_group@blacksheep.org; Thu, 17 Jun 2010 09:21:13 +0100 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 4F32B51C001 for ; Thu, 17 Jun 2010 10:21:00 +0200 (CEST) Received: from ICTS-S-HUB-N4.luna.kuleuven.be (icts-s-hub-n4.luna.kuleuven.be [10.112.9.14]) by smtps02.kuleuven.be (Postfix) with ESMTP id 2E20BF3862 for ; Thu, 17 Jun 2010 10:21:00 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N4.luna.kuleuven.be ([10.112.9.14]) with mapi; Thu, 17 Jun 2010 10:21:00 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Thu, 17 Jun 2010 10:21:00 +0200 Thread-Topic: LF: RE: Who needs antennas! - success with ground electrodes on 500kHz Thread-Index: AcsN9AGcAv3P7LVSRuGinxtIbDdEEgAAPQlr Message-ID: References: <648287CF-49D0-4E2E-BCE5-B20F634C9384@numeo.fr> <569132.43932.qm@web81107.mail.mud.yahoo.com>, In-Reply-To: Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 0.4 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126,MAILTO_TO_SPAM_ADDR=0.276 Subject: RE: LF: RE: Who needs antennas! - success with ground electrodes on 500kHz Content-Type: multipart/alternative; boundary="_000_BF4A524700075746A6467658DFC7102C5107CB128EICTSSEXC2CAlu_" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: ** X-Spam-Status: No, hits=2.1 required=5.0 tests=HTML_30_40,HTML_FONTCOLOR_BLUE, HTML_MESSAGE,HTML_TAG_EXISTS_TBODY,MAILTO_TO_SPAM_ADDR, 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 x-aol-global-disposition: G x-aol-sid: 3039ac1d410d4c19db400be4 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C5107CB128EICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Roger, 18 UTC is still daylight this time of the year. If you want to try a late evening or overnight run I can put on a WSPR RX= station. Regarding the ground loop as RX antenna: as long as the RX noise floor inc= reases when you connect the antenna the gain/effeciency in not so importan= t. Far more important is the kind of (and amount of) QRM/QRN picked up by= the antenna, loops tend to be less sensitive to local QRM sources (energy= saving lamps, switched PSU's of all kinds etc...). 73, Rik ON7YD - OR7T ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens Roger Lapthorn [rogerlapthorn@gmail.com] Verzonden: donderdag 17 juni 2010 10:01 Aan: rsgb_lf_group@blacksheep.org Onderwerp: Re: LF: RE: Who needs antennas! - success with ground electrode= s on 500kHz It is about 44-70kms with M0BMU being the furtherest (see WSPR log). 73s Roger G3XBM On 17 June 2010 02:38, Paul Cianciolo > wrote: Can you tell us what the distance is between Roger and M0BMU, G7NKS and M0= JXM ??? PaulC --- On Wed, 6/16/10, John Rabson > wrote: From: John Rabson > Subject: Re: LF: RE: Who needs antennas! - success with ground electrodes= on 500kHz To: rsgb_lf_group@blacksheep.org Date: Wednesday, June 16, 2010, 4:11 PM Some years ago, the Cave Radio & Electronics Group was conducting tests on= 87 kHz between surface and underground at Roger Kirk Cave near Ribblehead= viaduct in Yorkshire. After we had finished the tests I tuned the surface= receiver up to 136 and got very good signals from EI0CF. Unfortunately th= ere was no mobile phone service at the site so we could not let him know= immediately. We did send him a QSL card. 73 John F5VLF/G3PAI On 16 Jun 2010, at 21:51CEST, Roger Lapthorn wrote: Correction - I'm also copying PE1GRL at -18dB S/N using the earth electrod= e set-up! 73s Roger G3XBM On 16 June 2010 20:43, Dave G3WCB > wrote: That's pretty amazing. You must have really bad soil conductivity. Did you= try receiving on the earth-loop antenna? Would the technique work on 137 kHz, I wonder. 73, Dave G3WCB IO91RM, nr Windsor, S.E. England -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_gr= oup@blacksheep.org]On Behalf Of Roger Lapthorn Sent: 16 June 2010 20:11 To: rsgb_lf_group@blacksheep.org Subject: LF: Who needs antennas! - success with ground electrodes on 500kH= z Well, I'm amazed. This evening I connected my 500kHz transverter straight to the two connect= ions of my sub-9kHz grounded electrodes and TXed WSPR. No attempt was made= to match anything on the assumption that the two electrodes system looked= not too far from 50 ohms resistive as measured between 1-9kHz.. Pout from= the IRF510 is around 5W. What happened? Three people copied me - M0BMU, G7NKS and M0JXM with reports between -21= and -28dB S/N. The wire to the furtherest ground rod is at most 20m long= and most of the way it is 1.5m above ground. Once again, this must be act= ing as a pretty effective loop mostly within the ground. Screen grab of= the WSPR log attached. So, if you live on clunchy chalk soils like me then don't worry too much= about big antennas, :-) 73s Roger G3XBM -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 --_000_BF4A524700075746A6467658DFC7102C5107CB128EICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Roger,
 
18 UTC is still daylight this time= of the year.
If you want to try a late evening or= overnight run I can put on a WSPR RX station.
 
Regarding the ground loop as RX ante= nna: as long as the RX noise floor increases when you connect the antenna= the gain/effeciency in not so important. Far more important is the kind= of (and amount of) QRM/QRN picked up by the antenna, loops tend to be less sensitive to local QRM sources (energy sav= ing lamps, switched PSU's of all kinds etc...).
 
73, Rik  ON7YD - OR7T
 
Van: owner-rsgb_= lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Roger= Lapthorn [rogerlapthorn@gmail.com]
Verzonden: donderdag 17 juni 2010 10:01
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: RE: Who needs antennas! - success with ground el= ectrodes on 500kHz

It is about 44-70kms with M0BMU being the furtherest (see WSPR log).<= br>
73s
Roger G3XBM

On 17 June 2010 02:38, Paul Cianciolo <paulc@snet.net> wrote:
Can you tell us what the distance is between Roger and M0BMU, G7NKS= and M0JXM ???
 
PaulC


--- On Wed, 6/16/10, John Rabson <john.rabson@numeo.fr> wrote:

From: John Rabson <john.rabson@= numeo.fr>
Subject: Re: LF: RE: Who needs antennas! - success with ground electrodes= on 500kHz

To: rsgb_lf_group@blackshe= ep.org
Date: Wednesday, June 16, 2010, 4:11 PM


Some years ago, the Cave Radio & Electronics Group was conducting= tests on 87 kHz between surface and underground at Roger Kirk Cave near= Ribblehead viaduct in Yorkshire. After we had finished the tests I tuned= the surface receiver up to 136 and got very good signals from EI0CF. Unfortunately there was no mobile phone service= at the site so we could not let him know immediately. We did send him a= QSL card.

 73
John F5VLF/G3PAI

On 16 Jun 2010, at 21:51CEST, Roger Lapthorn wrote:

Correction - I'm also copying PE1GRL at= -18dB S/N using the earth electrode set-up!

73s
Roger G3XBM

On 16 June 2010 20:43, Dave G3WCB <ganymede444@btope= nworld.com> wrote:
That's pretty= amazing. You must have really bad soil conductivity. Did you try receivin= g on the earth-loop antenna?
 
Would the tec= hnique work on 137 kHz, I wonder.
 
73, Dave G3WC= B IO91RM, nr Windsor, S.E. England
-----Orig= inal Message-----
From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org]On= Behalf Of Roger Lapthorn
Sent: 16 June 2010 20:11
To: rsgb_lf_group@blacksheep.org
Subject: LF: Who needs antennas! - success with ground electrodes= on 500kHz

Well, I'm amazed.

This evening I connected my 500kHz transverter straight to the two connect= ions of my sub-9kHz grounded electrodes and TXed WSPR. No attempt was made= to match anything on the assumption that the two electrodes system looked= not too far from 50 ohms resistive as measured between 1-9kHz.. Pout from the IRF510 is around 5W. What happ= ened?

Three people copied me - M0BMU, G7NKS and M0JXM with reports between= -21 and -28dB S/N. The wire to the furtherest ground rod is at most 20m= long and most of the way it is 1.5m above ground. Once again, this must= be acting as a pretty effective loop mostly within the ground.  Screen grab of the WSPR log attached.

So, if you live on clunchy chalk soils like me then don't worry too much= about big antennas, :-)

73s
Roger G3XBM

--
http://g3xbm-qrp.blogspot.com/
htt= p://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
G3XBM    GQRP 1678      ISWL G11088



--
http://g3xbm-qrp.blogspot.com/
htt= p://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
G3XBM    GQRP 1678      ISWL G11088



--
http://g3xbm-= qrp.blogspot.com/
http://www.g3xbm.co.u= k
http://www= .youtube.com/user/g3xbm
G3XBM    GQRP 1678      ISWL G11088
--_000_BF4A524700075746A6467658DFC7102C5107CB128EICTSSEXC2CAlu_--