Return-Path: Received: from mtain-mg05.r1000.mx.aol.com (mtain-mg05.r1000.mx.aol.com [172.29.96.205]) by air-md08.mail.aol.com (v129.10) with ESMTP id MAILINMD083-8b924db860932e3; Wed, 27 Apr 2011 14:29:39 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mg05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 74E41380000E1; Wed, 27 Apr 2011 14:29:33 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QF9So-0007TJ-Sk for rs_out_1@blacksheep.org; Wed, 27 Apr 2011 19:27:50 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QF9Sn-0007TA-GY for rsgb_lf_group@blacksheep.org; Wed, 27 Apr 2011 19:27:49 +0100 Received: from out1.ip01ir2.opaltelecom.net ([62.24.128.237]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QF9Sl-0004LB-DB for rsgb_lf_group@blacksheep.org; Wed, 27 Apr 2011 19:27:49 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApEBAJxfuE1Olmbt/2dsb2JhbAAM6niFdgSSf4l/ X-IronPort-AV: E=Sophos;i="4.64,275,1301871600"; d="scan'208,217";a="350819790" Received: from unknown (HELO [192.168.2.2]) ([78.150.102.237]) by out1.ip01ir2.opaltelecom.net with ESMTP; 27 Apr 2011 19:27:40 +0100 Message-ID: <4DB8601C.8010402@talktalk.net> Date: Wed, 27 Apr 2011 19:27:40 +0100 From: qrss User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <4DB8535B.7040903@talktalk.net> In-Reply-To: X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: More 8.97kHz WSPR decodes - changed PC here Content-Type: multipart/alternative; boundary="------------060805080206000307090806" 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_20_30,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-sid: 3039ac1d60cd4db8608d47ef X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --------------060805080206000307090806 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi Roger Highly unlikely is very good compared with 'impossible to get past your own garden fence' and good signals from the Czech Republic. Also 'no intention to radiate' doesn't prevent it happening, we just don't know do we. That could be the answer to your being intrigued. I sure am not going to say it's impossible over this distance, there will be hundreds of missed opportunities soon, it's no trouble to try when I can. 73 Eddie On 27/04/2011 18:58, Roger Lapthorn wrote: > Hi Eddie (et al) > > It is highly unlikely you'd copy Andrew on VLF remembering that the > WSPR signal spreads around 6Hz in the transmission burst, so the > energy in any narrow FFT bin would be tiny. Also, this is earth mode > (I hope, as G6ALB does not hold an NoV to radiate at VLF), so signals > are propagating through the ground by conduction and no significant > amount of signal is radiated. > > I'm still intrigued why the best reception here today was with my 80sq > m vertical loop. This outperformed several earth electrode set-ups > here at the RX end, an E-field probe and a 30t loop laying close to > copper pipe work in the house! If the signals are coming down the > pipes then why don't these more direct means of coupling to them work > as well as (or better than) a vertical loop outside? Odd. > > 73s > Roger G3XBM > > > > On 27 April 2011 18:33, qrss > wrote: > > Great stuff Roger and Andrew > > If you are RX'ing on an 80m dipole it may be worth a look here, I > would never say can't until I have tried. Bearing in mind I should > be able to observe signals which would not be decode able on WSPR > > I would appreciate a prior notification of times and exact > frequency of the WSPR signal of any further tests. > > Keep it up. > > 73 Eddie G3ZJO > > > On 27/04/2011 15:19, Roger Lapthorn wrote: > > As an experiment I changed over to my wife's laptop and got > immediate decodes of G6ALB's VLF earth mode signal (3km) at > -17dB S/N, suggesting the issue with lack of decodes may be > with my soundcard and not Andrew's. > > 1408 -17 -0.6 0.008986 0 G6ALB JO02 47 > 1410 -17 -0.6 0.008986 0 G6ALB JO02 47 > 1412 -17 -1.2 0.008986 0 G6ALB JO02 47 > 1414 -17 -0.8 0.008986 0 G6ALB JO02 47 > 1416 -17 -0.8 0.008986 0 G6ALB JO02 47 > > This is a very solid signal on the 80m square single turn > vertical wire loop antenna. Andrew is using 44W to an earth > electrode antenna. > > 73s > Roger G3XBM > > -- > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/g3xbm > https://sites.google.com/site/sub9khz/ > > > > > > > -- > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/g3xbm > https://sites.google.com/site/sub9khz/ > --------------060805080206000307090806 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi Roger

Highly unlikely is very good compared with 'impossible to get past your own garden fence' and good signals from the Czech Republic.
Also 'no intention to radiate' doesn't prevent it happening, we just don't know do we. That could be the answer to your being intrigued.
I sure am not going to say it's impossible over this distance, there will be hundreds of missed opportunities soon, it's no trouble to try when I can.

73 Eddie

On 27/04/2011 18:58, Roger Lapthorn wrote:
Hi Eddie (et al)

It is highly unlikely you'd copy Andrew on VLF remembering that the WSPR signal spreads around 6Hz in the transmission burst, so the energy in any narrow FFT bin would be tiny. Also, this is earth mode (I hope, as G6ALB does not hold an NoV to radiate at VLF), so signals are propagating through the ground by conduction and no significant amount of signal is radiated.

I'm still intrigued why the best reception here today was with my 80sq m vertical loop. This outperformed several earth electrode set-ups here at the RX end, an E-field probe and a 30t loop laying close to copper pipe work in the house!  If the signals are coming down the pipes then why don't these more direct means of coupling to them work as well as (or better than) a vertical loop outside? Odd.

73s
Roger G3XBM



On 27 April 2011 18:33, qrss <qrss@talktalk.net> wrote:
Great stuff Roger and Andrew

If you are RX'ing on an 80m dipole it may be worth a look here, I would never say can't until I have tried. Bearing in mind I should be able to observe signals which would not be decode able on WSPR

I would appreciate a prior notification of times and exact frequency of the WSPR signal of any further tests.

Keep it up.

73 Eddie G3ZJO


On 27/04/2011 15:19, Roger Lapthorn wrote:
As an experiment I changed over to my wife's laptop and got immediate decodes of G6ALB's VLF earth mode signal (3km) at -17dB S/N, suggesting the issue with lack of decodes may be with my soundcard and not Andrew's.

1408 -17 -0.6   0.008986  0 G6ALB JO02 47
1410 -17 -0.6   0.008986  0 G6ALB JO02 47
1412 -17 -1.2   0.008986  0 G6ALB JO02 47
1414 -17 -0.8   0.008986  0 G6ALB JO02 47
1416 -17 -0.8   0.008986  0 G6ALB JO02 47

This is a very solid signal on the 80m square single turn vertical wire loop antenna. Andrew is using 44W to an earth electrode antenna.

73s
Roger G3XBM

--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
https://sites.google.com/site/sub9khz/






--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
https://sites.google.com/site/sub9khz/


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