Return-Path: Received: from mtain-md08.r1000.mx.aol.com (mtain-md08.r1000.mx.aol.com [172.29.96.92]) by air-md08.mail.aol.com (v129.4) with ESMTP id MAILINMD081-8b904d2ca7122d2; Tue, 11 Jan 2011 13:53:06 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-md08.r1000.mx.aol.com (Internet Inbound) with ESMTP id 13B7938000127; Tue, 11 Jan 2011 13:53:04 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PcjKC-0002KL-F1 for rs_out_1@blacksheep.org; Tue, 11 Jan 2011 18:52:08 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PcjKB-0002KC-Jo for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 18:52:07 +0000 Received: from mail-iw0-f171.google.com ([209.85.214.171]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PcjK8-0001XI-EY for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 18:52:07 +0000 Received: by iwn2 with SMTP id 2so20748506iwn.16 for ; Tue, 11 Jan 2011 10:52:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=Z6fLqN8nNMNh7Qm+8X/U+vKlJkf7qW6sd5w8sSqG1t8=; b=nc8O+hx61rrUxszsUkuZEwS80o9lotEW7yiTLKsyIG2GTCxpXOvnkLDXNkr7lHgQ2S 6hBAt2JdgQg5DvFOvHbvCDrzoKdg0gn1JtPavwtFXLYLfepf+qh7Yu+jMCYLuG7YE3ff QVcasYHSjvZmLDOyfgQZ9HmY0qtsdmF5wTgFg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=REKEbwFYu6cMyPdOdAMjjlGl/uGIcMj5eRwWSX+YRfxeyA+AE7G7f0+zyFIFPap8gm 5mGlqn6vcKe7PwrwsGEcrvY5vhe7GEDomZEn7EXy2J3Yg7qYvcFxTesVsE+egg7WSED7 M39ch9I2FPz4dsKvre/1+0FkItKeSp00VW2sU= MIME-Version: 1.0 Received: by 10.231.207.73 with SMTP id fx9mr19787346ibb.137.1294771923186; Tue, 11 Jan 2011 10:52:03 -0800 (PST) Received: by 10.231.200.211 with HTTP; Tue, 11 Jan 2011 10:52:03 -0800 (PST) In-Reply-To: References: Date: Tue, 11 Jan 2011 18:52:03 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126 Subject: Re: LF: Re: Increased ERP on 137.5kHz - WSPR reports please Content-Type: multipart/alternative; boundary=90e6ba53a55e8bf5f4049996947f X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.2 required=5.0 tests=HTML_FONTCOLOR_UNSAFE, HTML_MESSAGE,HTML_TAG_EXISTS_TBODY 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-AUTHENTICATION: mail_rly_antispam_dkim-d231.1 ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d605c4d2ca710050e X-AOL-IP: 195.171.43.25 X-Mailer: Unknown (No Version) --90e6ba53a55e8bf5f4049996947f Content-Type: text/plain; charset=ISO-8859-1 Odd. At 3km G6ALB 'ought' to be in the true far field. but I do wonder if there could be some ground current "ducting" - eg if you have any underground power-cable runs in common. You' be on separate 415V circuits / substations but 3km is close enough to have the same 11kV feeder serving them ? Or any other cables Just a thought Andy www.g4jnt.com On 11 January 2011 18:43, Roger Lapthorn wrote: > 0.18A and an assumed Heffective of 3m Andy. > > 73s > Roger G3XBM > > > On 11 January 2011 18:39, Andy Talbot wrote: > >> What antenna current are you getting? >> - OR - >> What is the total resonant input resistance of the vertical + ground >> system (before any matching network) .and the RF power being delivered into >> this, >> >> Either of these will allow a reasonable estimate of ERP >> >> Andy >> www.g4jnt.com >> >> >> >> >> On 11 January 2011 18:26, Roger Lapthorn wrote: >> >>> So much for the theory then.... >>> >>> The signal level at G6ALB in the next village (3km although WSPR shows it >>> as 0km) is some 10dB *down* on my loop antenna. Not sure if I got my >>> sums wrong or there is some unexplained loss. The RX system at G6ALB is >>> unchanged. >>> >>> 73s >>> Roger G3XBM >>> >>> On 11 January 2011 17:32, Roger Lapthorn wrote: >>> >>>> Dear All, >>>> >>>> Today I rigged up and matched a simple, small, Marconi vertical on >>>> 136kHz instead of the vertical loop. Based on measurements of antenna >>>> current and some reasonable assumptions of effective height, I now believe I >>>> have around 200uW ERP on the band - heck this is *high* power for me! >>>> >>>> From now until late this evening I will run the WSPR beacon (136kHz USB >>>> dial) in the hope that a few more people will be able to copy the QRPp >>>> signal. Please have a go and let me have any reports. >>>> >>>> 73s and good luck >>>> >>>> Roger G3XBM >>>> >>>> -- >>>> g3xbm-qrp.blogspot.com/ >>>> www.g3xbm.co.uk >>>> www.youtube.com/user/g3xbm >>>> G3XBM GQRP 1678 ISWL G11088 >>>> >>> >>> >>> >>> -- >>> g3xbm-qrp.blogspot.com/ >>> www.g3xbm.co.uk >>> www.youtube.com/user/g3xbm >>> G3XBM GQRP 1678 ISWL G11088 >>> >>> >>> >>> >>> >>> >> >> > > > -- > g3xbm-qrp.blogspot.com/ > www.g3xbm.co.uk > www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 > > > > > > --90e6ba53a55e8bf5f4049996947f Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Odd.
At 3km G6ALB 'ought' to be in the true far field. but I do wo= nder if there could be some ground current "ducting"
=A0
- eg if you have any underground power-cable runs in common.=A0=A0=A0= You' be on separate 415V circuits=A0/ substations but =A03km is close= enough to have the same 11kV feeder serving them ?
=A0
Or any other cables
=A0
Just a thought
=A0
Andy
=A0

On 11 January 2011 18:43, Roger Lapthorn <rogerlapthorn@= gmail.com> wrote:
0.18A and an assumed Heffectiv= e of 3m Andy.

73s
Roger G3XBM=20


On 11 January 2011 18:= 39, Andy Talbot <andy.g4jnt@gmail.com> wrote:
What antenna current are you getting?
=A0- OR -
What is the total resonant input resistance of the vertical + ground= system (before any matching network) .and the RF power being delivered in= to this,
=A0
Either of =A0these will allow a reasonable estimate of ERP
=A0
Andy
=A0


=A0
On 11 January 2011 18:26, Roger Lapthorn <rogerlapthorn@gmail.com> wrote:
So much for the= theory then....

The signal level at G6ALB in the next village (3km= although WSPR shows it as 0km) is some 10dB down on my loop antenn= a. Not sure if I got my sums wrong or there is some unexplained loss. The= RX system at G6ALB is unchanged.

73s
Roger G3XBM

On 11 January 2011 17:= 32, Roger Lapthorn <rogerlapthorn@gmail.com> wrote:<= br>
Dear All,

= Today I rigged up and matched a simple, small, Marconi vertical on 136kHz= instead of the vertical loop. Based on measurements of antenna current an= d some reasonable assumptions of effective height, I now believe I have ar= ound 200uW ERP on the band - heck this is high power for me!

From now until late this evening I will run the WSPR beacon (136kHz US= B dial) in the hope that a few more people will be able to copy the QRPp= signal. Please have a go and let me have any reports.

73s and good= luck

Roger G3XBM

--
g3xbm-qrp.blogspot.= com/
www.g3xb= m.co.uk
www.youtub= e.com/user/g3xbm
= G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088



--
g3= xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM=A0=A0 GQRP 167= 8=A0=A0=A0 ISWL G11088
3D""
=A0 =A0
=A0
=3D"" =A0 =3D"" =A0 =A0 =A0
=A0
=A0
=



--
g3xbm-qrp.blogspot.c= om/
www.g3xbm.co.uk<= br>www.you= tube.com/user/g3xbm
G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088
3D""
=A0 =A0
=A0
=3D"" =A0 =3D"" =A0 =A0 =A0
=A0
=A0

--90e6ba53a55e8bf5f4049996947f--