Return-Path: Received: from mtain-dl11.r1000.mx.aol.com (mtain-dl11.r1000.mx.aol.com [172.29.74.217]) by air-da02.mail.aol.com (v129.4) with ESMTP id MAILINDA022-86124d2cc614178; Tue, 11 Jan 2011 16:05:24 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dl11.r1000.mx.aol.com (Internet Inbound) with ESMTP id 32668380000C2; Tue, 11 Jan 2011 16:05:21 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PclO7-0003gw-Nq for rs_out_1@blacksheep.org; Tue, 11 Jan 2011 21:04:19 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PclO6-0003gn-KA for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 21:04:18 +0000 Received: from mail-ww0-f47.google.com ([74.125.82.47]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PclO3-0002TI-Sc for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 21:04:18 +0000 Received: by wwb39 with SMTP id 39so21604727wwb.28 for ; Tue, 11 Jan 2011 13:04:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:references:from :content-type:x-mailer:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=QqF37ohLBA0uD3pu/FzqtFPf0h/LrvEvhmHmYuMwVX4=; b=ji+ZTsllqqR1VGrHqZOJsKrpXy1IxcLcm4inqMbDVELWr1FvrvS6LbaI8QsWdrys/X 9aylMl+ZUsss1gag7KCM1D6VvcU+htuWNralJLO/fEpC7axGsOffe9x4wkBBkgp+dKed gCzpFT1ubmC2x5uKrqJCZIH7aqwUD3ZKS7Stg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:references:from:content-type:x-mailer:in-reply-to :message-id:date:to:content-transfer-encoding:mime-version; b=SycfD78IESKOND34e5hQ46HCRD1fDFt+vM95Yw55KDzGNnH05Zpjsb7cpQC0Khily4 eQEMWAapfP76VCzz+PomMEIvzXeEVBVMOIkKNWDXmfbFDGDHk0ZHgpxld0Bl4Nl3aQW5 8v8WCvWQhKj0wiEnaX9C/y7/NShTjY0++9IQM= Received: by 10.227.168.79 with SMTP id t15mr68912wby.200.1294779850212; Tue, 11 Jan 2011 13:04:10 -0800 (PST) Received: from [192.168.1.101] (cpc3-cmbg14-0-0-cust445.5-4.cable.virginmedia.com [213.106.93.190]) by mx.google.com with ESMTPS id 11sm21269135wbi.18.2011.01.11.13.04.06 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 11 Jan 2011 13:04:08 -0800 (PST) References: From: Roger Lapthorn X-Mailer: iPod Mail (8C148) In-Reply-To: Message-Id: <95F786F2-4722-44F1-B787-879A560FF239@gmail.com> Date: Tue, 11 Jan 2011 21:05:07 +0000 To: "rsgb_lf_group@blacksheep.org" Mime-Version: 1.0 (iPod Mail 8C148) 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=Apple-Mail-5-792616947 Content-Transfer-Encoding: 7bit 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,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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d306.2 ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d4ad94d2cc6112c92 X-AOL-IP: 195.171.43.25 --Apple-Mail-5-792616947 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Yes Rik, the ferrite rod ATU is just sitting on the bedroom table. I used= a similar arrangement quite successfully on 500kHz but this, plus the ver= y short vertical, are not good enough on 136kHz. At QRP levels I think a= ferrite rod is OK in an ATU but I need more wire in the air. 73s Roger G3XBM Sent from my iPod Touch 4g On 11 Jan 2011, at 20:39, Rik Strobbe wrote: > Hello Roger, > =20 > "coil on the bedroom table" : do you have the loading coil indoors ? > It might be worth trying to place the coil outside to reduce losses. > =20 > 73, Rik ON7YD=20 > =20 > Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.= org] namens Roger Lapthorn [rogerlapthorn@gmail.com] > Verzonden: dinsdag 11 januari 2011 20:13 > Aan: rsgb_lf_group@blacksheep.org > Onderwerp: Re: LF: Re: Increased ERP on 137.5kHz - WSPR reports please >=20 > This agrees well with my calculation Rik. As I said, the issue is where= the power is going: with such a short vertical section (5m long and assum= ed Heff of 3m) without any real top loading most of the energy is being di= ssipated in the coil on the bedroom table. >=20 > Currently TXing into the earth electrodes and G6ALB is getting me at -18= dB S/N at 3km. I've a lot of work to do... >=20 > 73s > Roger g3XBM >=20 > On 11 January 2011 19:03, Rik Strobbe wrot= e: > Hello Roger, > =20 > 3m Heff @ 2200m --> Rrad =3D 1580*(3/2200)^2 =3D +/- 0.003 Ohm > radiated power =3D 0.18^2*0.003 =3D +/- 100uW > Gain of a short vertical =3D 1.83 --> ERP =3D +/- 180uW > But "greenery loss" can be up to 6dB (or even more), so instead of 180uW= it could less than 50uW as well. > =20 > I have wspr running, being very very optimistic ;-) > =20 > 73, Rik ON7YD - OR7T > =20 > Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.= org] namens Roger Lapthorn [rogerlapthorn@gmail.com] > =20 > =20 > =20 > =20 > =20 >=20 > Verzonden: dinsdag 11 januari 2011 19:43 > Aan: rsgb_lf_group@blacksheep.org > Onderwerp: Re: LF: Re: Increased ERP on 137.5kHz - WSPR reports please >=20 > 0.18A and an assumed Heffective of 3m Andy. >=20 > 73s > Roger G3XBM >=20 > 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 sys= tem (before any matching network) .and the RF power being delivered into= this, > =20 > Either of these will allow a reasonable estimate of ERP > =20 > Andy > www.g4jnt.com > =20 >=20 >=20 > =20 > On 11 January 2011 18:26, Roger Lapthorn wrote= : > So much for the theory then.... >=20 > 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 sum= s wrong or there is some unexplained loss. The RX system at G6ALB is uncha= nged. >=20 > 73s > Roger G3XBM >=20 > On 11 January 2011 17:32, Roger Lapthorn wrote= : > Dear All, >=20 > Today I rigged up and matched a simple, small, Marconi vertical on 136kH= z 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! >=20 > 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 si= gnal. Please have a go and let me have any reports. >=20 > 73s and good luck >=20 > Roger G3XBM >=20 > --=20 > g3xbm-qrp.blogspot.com/ > www.g3xbm.co.uk > www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 >=20 >=20 >=20 > --=20 > g3xbm-qrp.blogspot.com/ > www.g3xbm.co.uk > www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 > =20 > =20 > =20 > =20 > =20 >=20 >=20 >=20 >=20 > --=20 > g3xbm-qrp.blogspot.com/ > www.g3xbm.co.uk > www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 >=20 >=20 >=20 > --=20 > g3xbm-qrp.blogspot.com/ > www.g3xbm.co.uk > www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 --Apple-Mail-5-792616947 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8
Yes Rik, the ferrite rod ATU is just= sitting on the bedroom table. I used a similar arrangement quite successf= ully on 500kHz but this, plus the very short vertical, are not good enough= on 136kHz. At QRP levels I think a ferrite rod is OK in an ATU but I need= more wire in the air.

73s
Roger G3XBM<= br>
Sent from my iPod Touch 4g

On 11 Jan 2011, at 20:39,= Rik Strobbe <Rik.Strobb= e@fys.kuleuven.be> wrote:

Hello Roger,
 
"coil on the bedroom table" : do you= have the loading coil indoors ?
It might be worth trying to place th= e coil outside to reduce losses.
 
73, Rik  ON7YD 
 
Van: owner-rsgb_lf_group@blacksheep.= org [owner-rsgb_= lf_group@blacksheep.org] namens Roger Lapthorn [rogerlapthorn@gmail.com]
Verzonden: dinsdag 11 januari 2011 20:13
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: Re: Increased ERP on 137.5kHz - WSPR reports ple= ase

This agrees well with my calculation Rik. As I said, the issue is whe= re the power is going: with such a short vertical section (5m long and ass= umed Heff of 3m) without any real top loading most of the energy is being= dissipated in the coil on the bedroom table.

Currently TXing into the earth electrodes and G6ALB is getting me at -18dB= S/N at 3km. I've a lot of work to do...

73s
Roger g3XBM

On 11 January 2011 19:= 03, Rik Strobbe <Rik.Strobbe@fys.kuleuven.be<= /a>> wrote:
Hello Roger,
 
3m Heff @ 2200m --> Rrad =3D 1580= *(3/2200)^2 =3D +/- 0.003 Ohm
radiated power =3D 0.18^2*0.003 =3D= +/- 100uW
Gain of a short vertical =3D 1.83 --= > ERP =3D +/- 180uW
But "greenery loss" can be up to 6dB= (or even more), so instead of 180uW it could less than 50u= W as well.
 
I have wspr running, being very very= optimistic ;-)
 
73, Rik  ON7YD - OR7T
 
Van: owner-rsgb_lf_group@= blacksheep.org [owner-rsgb_lf_gr= oup@blacksheep.org] namens Roger Lapthorn [rogerlaptho= rn@gmail.com]
   
 
       
 
 

Verzonden: dinsdag 11 januari 2011 19:43
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: Re: Increased ERP on 137.5kHz - WSPR reports ple= ase

0.18A and an assumed Heffective of 3m Andy.

73s
Roger G3XBM

On 11 January 2011 18:= 39, Andy Talbot <andy.g4jnt@gmail.com> 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 in= to this,
 
Either of  these will allow a reasonable estimate of ERP
 
Andy
 


 
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 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 <rogerlapthorn@gmail.com> 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 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 USB di= al) in the hope that a few more people will be able to copy the QRPp signa= l. 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   GQ= RP 1678    ISWL G11088



--
g3xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM   GQ= RP 1678    ISWL G11088
   
 
       
 
 
<= /a>




--
g3xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM   GQR= P 1678    ISWL G11088



--
g3xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM   GQR= P 1678    ISWL G11088
   
 
       
 
 
=
=3D --Apple-Mail-5-792616947--