Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-da05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2E1BB38000093; Mon, 15 Aug 2011 13:46:43 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Qt1EV-00063C-ID for rs_out_1@blacksheep.org; Mon, 15 Aug 2011 18:45:51 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Qt1EU-000633-SN for rsgb_lf_group@blacksheep.org; Mon, 15 Aug 2011 18:45:50 +0100 Received: from mail-yw0-f43.google.com ([209.85.213.43]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Qt1ES-0007vk-88 for rsgb_lf_group@blacksheep.org; Mon, 15 Aug 2011 18:45:50 +0100 Received: by ywm3 with SMTP id 3so1087014ywm.16 for ; Mon, 15 Aug 2011 10:45:41 -0700 (PDT) Received: by 10.151.102.7 with SMTP id e7mr5331517ybm.266.1313430341065; Mon, 15 Aug 2011 10:45:41 -0700 (PDT) MIME-Version: 1.0 Received: by 10.151.102.7 with SMTP id e7mr5331513ybm.266.1313430340897; Mon, 15 Aug 2011 10:45:40 -0700 (PDT) Received: by 10.151.49.13 with HTTP; Mon, 15 Aug 2011 10:45:40 -0700 (PDT) In-Reply-To: References: <8F12A13F-4174-4C0F-8916-1543A69C2E65@gmail.com> <17BB4B3F-F338-4973-8F87-BD710C9C1539@numeo.fr> Date: Mon, 15 Aug 2011 18:45:40 +0100 Message-ID: From: "Steve, g4vbd" To: rsgb_lf_group@blacksheep.org X-Spam-Score: 0.9 (/) X-Spam-Report: autolearn=disabled,DNS_FROM_RFC_WHOIS=0.879,HTML_MESSAGE=0.001 Subject: Re: LF: Ferrite rods Content-Type: multipart/alternative; boundary=00151750efc0e80aad04aa8ed468 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30, HTML_FONTCOLOR_UNSAFE,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-SCORE: 0:2:432493536:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d404d4e495b8340e1 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --00151750efc0e80aad04aa8ed468 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Guys Its =A349.00 from this web site http://www.lulu.com/product/paperback/channel-characterisation-and-system-d= esign-for-sub-surface-communications/11253100 too expensive for me - but if you find a pdf then I'd be interested as well Found this though Electrode Contact Impedance Measurement in Through-The-Earth Communications http://dcis2009.unizar.es/FILES/CR2/p30.pdf regards Steve, g4vbd On Mon, Aug 15, 2011 at 12:02 PM, Roger Lapthorn w= rote: > Is this PhD document publically available as a PDF John? > > 73s > Roger G3XBM > > > On 15 August 2011 11:26, John Rabson wrote: > >> There is an extensive discussion of ferrite rod antennas in Chapter 4 of= : >> >> Gibson, David (2004) Channel Characterisation and System Design f= or >> Sub-Surface Communications PhD thesis, Leeds University 2004. >> >> John >> F5VLF >> >> On 15 Aug 2011, at 09:46CEST, Roger Lapthorn wrote: >> >> > Although I've little experience of ferrite rods on LF receive I did wi= nd >> my 600uH 500kHz ATU loading coil for my 5w transverter on one. With jus= t a >> 5m top loaded vertical it worked well without saturation problems when >> sitting on the bedroom table. At QRP it is less lossy as less wire is >> needed. >> > >> > People have successfully engineered (single turn I think) ferrite rods >> as TX antennas for 10MHz QRPp WSPR. Somewhere I have some information on >> this. As long as saturation is avoided there is some mileage for HF TX >> applications in very compact QRP stations. >> > >> > Worth some experiments on LF receive Stefan. >> > >> > 73s >> > Roger G3XBM >> > >> > Via my iPod Touch 4g 2.4GHz handheld. >> > >> >> >> > > > -- > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/g3xbm > https://sites.google.com/site/sub9khz/ > > --00151750efc0e80aad04aa8ed468 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Guys
Its =A349.00 from this web site
=A0
http://www.lulu.= com/product/paperback/channel-characterisation-and-system-design-for-sub-su= rface-communications/11253100
=A0
too expensive for me - but if you find a pdf then I'= d be interested as well
Found this though

Electrode Conta= ct Impedance Measurement in Through-The-Earth Communications



=A0
On Mon,= Aug 15, 2011 at 12:02 PM, Roger Lapthorn <rogerlapthorn@gmail.com> wrot= e:
Is this PhD document publically available as a= PDF John?

73s
Roger G3XBM


On 15 August 2011 11:26, John Rabson <= ;john.rabson@nume= o.fr> wrote:
There is an extensive discussion of ferrite ro= d antennas in Chapter 4 of:

=A0 =A0 =A0 =A0Gibson, David (2004) Channel Characterisation and System De= sign for Sub-Surface Communications PhD thesis, Leeds University 2004.

John
F5VLF

On 15 Aug 2011, at 09:46CEST, Roger Lapthorn wrote:

> Although I've little experience of ferrite rods on LF receive I di= d wind my 600uH 500kHz ATU loading coil for my 5w transverter on one. =A0Wi= th just a 5m top loaded vertical it worked well without saturation problems= when =A0sitting on the bedroom table. At QRP it is less lossy as less wire= is needed.
>
> People have successfully engineered (single turn I think) ferrite rods= as TX antennas for 10MHz QRPp WSPR. Somewhere I have some information on t= his. As long as saturation is avoided there is some mileage for HF TX appli= cations in very compact QRP stations.
>
> Worth some experiments on LF receive Stefan.
>
> 73s
> Roger G3XBM
>
> Via my iPod Touch 4g 2.4GHz handheld.
>





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


--00151750efc0e80aad04aa8ed468--