Return-Path: Received: from mtain-ma08.r1000.mx.aol.com (mtain-ma08.r1000.mx.aol.com [172.29.96.16]) by air-de03.mail.aol.com (v129.4) with ESMTP id MAILINDE031-5eaa4d2cc0a2277; Tue, 11 Jan 2011 15:42:10 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-ma08.r1000.mx.aol.com (Internet Inbound) with ESMTP id 57EF9380000A3; Tue, 11 Jan 2011 15:42:08 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Pcl1b-0003Uh-NL for rs_out_1@blacksheep.org; Tue, 11 Jan 2011 20:41:03 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Pcl1a-0003UY-Nb for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 20:41:02 +0000 Received: from cavuit02.kulnet.kuleuven.be ([134.58.240.44]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Pcl1X-0002Ly-4e for rsgb_lf_group@blacksheep.org; Tue, 11 Jan 2011 20:41:02 +0000 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 48F0875A06E for ; Tue, 11 Jan 2011 21:40:44 +0100 (CET) Received: from ICTS-S-HUB-N2.luna.kuleuven.be (icts-s-hub-n2.luna.kuleuven.be [10.112.9.12]) by smtps02.kuleuven.be (Postfix) with ESMTP id 4447BF3862 for ; Tue, 11 Jan 2011 21:40:44 +0100 (CET) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N2.luna.kuleuven.be ([10.112.9.12]) with mapi; Tue, 11 Jan 2011 21:40:44 +0100 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Tue, 11 Jan 2011 21:39:16 +0100 Thread-Topic: LF: Re: Increased ERP on 137.5kHz - WSPR reports please Thread-Index: Acuxw+UuiQCgXU5ORW2CXmWcw2WyAwAC7hkO Message-ID: References: , 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: 0.1 (/) 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="_000_BF4A524700075746A6467658DFC7102C88715AEA4AICTSSEXC2CAlu_" 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-sid: 3039ac1d60104d2cc0a065a5 X-AOL-IP: 195.171.43.25 X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C88715AEA4AICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello Roger, "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. 73, Rik ON7YD ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] 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 This agrees well with my calculation Rik. As I said, the issue is where th= e power is going: with such a short vertical section (5m long and assumed= Heff of 3m) without any real top loading most of the energy is being diss= ipated 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 > 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 50uW as well. I have wspr running, being very very optimistic ;-) 73, Rik ON7YD - OR7T ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Roger Lapthorn [rogerlapthorn@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 please 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 syste= m (before any matching network) .and the RF power being delivered into thi= s, 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 unchan= ged. 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 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 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 -- g3xbm-qrp.blogspot.com/ www.g3xbm.co.uk www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 --_000_BF4A524700075746A6467658DFC7102C88715AEA4AICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
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.S= trobbe@fys.kuleuven.be> 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 tha= n 50uW as well.
 
I have wspr running, being very very= optimistic ;-)
 
73, Rik  ON7YD - OR7T
 
Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Roger= Lapthorn [rogerlapthorn@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@g= mail.com> wrote:
What antenna current are you getting?
 - OR -
What is the total resonant input resistance of the vertical + gro= und system (before any matching network) .and the RF power being delivered= into 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 <rogerlapt= horn@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.blo= gspot.com/
www.g3xbm.co.uk<= br> www.youtub= e.com/user/g3xbm
G3XBM   GQ= RP 1678    ISWL G11088



--
g3xbm-qrp.blo= gspot.com/
www.g3xbm.co.uk<= br> www.youtub= e.com/user/g3xbm
G3XBM   GQ= RP 1678    ISWL G11088
   
 
       
 
 
<= /a>




--
g3xbm-qrp.blo= gspot.com/
www.g3xbm.co.uk www.youtub= e.com/user/g3xbm
G3XBM   GQR= P 1678    ISWL G11088



--
g3xbm-qrp.blo= gspot.com/
www.g3xbm.co.uk www.youtub= e.com/user/g3xbm
G3XBM   GQR= P 1678    ISWL G11088
   
 
       
 
 
=
--_000_BF4A524700075746A6467658DFC7102C88715AEA4AICTSSEXC2CAlu_--