Return-Path: Received: from mtain-mj09.r1000.mx.aol.com (mtain-mj09.r1000.mail.aol.com [172.21.164.93]) by air-dc02.mail.aol.com (v129.4) with ESMTP id MAILINDC024-86a04cc02d2a38e; Thu, 21 Oct 2010 08:08:10 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mj09.r1000.mx.aol.com (Internet Inbound) with ESMTP id 438E3380000A0; Thu, 21 Oct 2010 08:08:08 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1P8ttx-0005LY-Hf for rs_out_1@blacksheep.org; Thu, 21 Oct 2010 13:05:45 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1P8ttw-0005LP-VM for rsgb_lf_group@blacksheep.org; Thu, 21 Oct 2010 13:05:44 +0100 Received: from mail-bw0-f43.google.com ([209.85.214.43]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1P8ttq-0002Hn-SD for rsgb_lf_group@blacksheep.org; Thu, 21 Oct 2010 13:05:44 +0100 Received: by bwz1 with SMTP id 1so188431bwz.16 for ; Thu, 21 Oct 2010 05:05:38 -0700 (PDT) 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=oGzy4WBm2GJMpGvE8PDEi2toBBVqr+3H0pVF7e7e70o=; b=WTxknJnzHFI3MBEYCdfqUZ/UQ9PPuflOW1ADnL4PKiX4Q6pcSyf51La1yXm/XEk2pO phK9J+WdLFuhNmd1zu1tTCpki4FRsxh79aj9dW7j6W3tL9gW6aNFD7ebNvyZIi8vjLws n7fa3GnyutbyBeDmGE3NlXgJew35STQX4MtT0= 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=Cd334xH5tskmxPp0sEmlEDK6/LC4vDs7VtKp6hsWDPz/6NDwh2O7DKfeTucWgfnGTg xsxW9w7O1JEyoePja28Ku74Cew2aGwtbl7py0E7SF3t9g6+erDl4O/XE8VUuinxSJyen TcqtM+5ktgRtXt+c4EwEEIBGqGKOkcH3WZvHM= MIME-Version: 1.0 Received: by 10.204.98.198 with SMTP id r6mr639297bkn.51.1287662737803; Thu, 21 Oct 2010 05:05:37 -0700 (PDT) Received: by 10.204.65.133 with HTTP; Thu, 21 Oct 2010 05:05:37 -0700 (PDT) In-Reply-To: References: Date: Thu, 21 Oct 2010 13:05:37 +0100 Message-ID: From: Roger Lapthorn To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: RE: New personal QRP DX record on 500kHz: 1733km Content-Type: multipart/alternative; boundary=001636499f7713ca1404931f58e8 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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m258.1 ; domain : gmail.com DKIM : pass x-aol-sid: 3039400c89b24cc02d273417 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --001636499f7713ca1404931f58e8 Content-Type: text/plain; charset=ISO-8859-1 No, the 500kHz TX, ATU and loop antenna are as they were a few weeks ago Rik and I am suprised how well this all works. The transverter (on my website) TX produces 5W from an IRF510 and this is fed to a vertical wire loop in the garden tuned with a capacitance decade box for maximum loop current. The loop is supported at the house end by the aluminium poll used to support the 28MHz halo (about 9m above ground at highest). The wire runs about 17m down to a tree where the far end is about 4m above ground. Then it runs down to the lawn and runs back along the ground (buried in the long grass that is wet and needs cutting) to the house. The feed is via an upstairs bedroom window with the ATU on the bedroom table. In all, the loop area is about 70 square metres. The wire is PVC covered 1mm diameter wire. The experts tell me I should raise the bottom of the loop above the ground, but just resting it on the wet grass doesn't seem to be doing too bad. The grass is about 10cm long at the moment as it is too wet to cut and we were away in South Africa for the last few weeks. I can increase the wire diameter soon which will increase the loop current some 3dB. I'd be interested to know what you believe my ERP is. My last calculation came out around 2mW. This evening I shall be back on 137.5kHz WSPR with the same antenna and ATU, although the ERP on 137.5kHz is much lower and almost certainly not more than 100uW at very best. 73s Roger G3XBM On 21 October 2010 07:47, Rik Strobbe wrote: > Hi Roger, > > congrats with teh new ODX. > Did you improve the setup ? > I had daytime copy of your signal up to -25dB at at night copy up to -18dB > (meaning you could have reduced power by another 13dB). > > 73, Rik ON7YD - OR7T > > ------------------------------ > *Van:* owner-rsgb_lf_group@blacksheep.org [ > owner-rsgb_lf_group@blacksheep.org] namens Roger Lapthorn [ > rogerlapthorn@gmail.com] > *Verzonden:* woensdag 20 oktober 2010 23:24 > *Aan:* rsgb_lf_group@blacksheep.org; GQRP@yahoogroups.com > *Onderwerp:* LF: New personal QRP DX record on 500kHz: 1733km > > This evening, quite unexpectedly, I got a string of reports on 500kHz > WSPR from *OH1LSQ* in KP03sd at an astounding distance of 1733km. To me > these are amazing reports pushing my best DX on the band with just a few > milliwatts ERP to new levels. What surprises me is how well a very simple > vertical wire loop works as a TX antenna: the wire is just 1mm diameter, > with an area of around 70m square with part of the loop laying on the ground > buried in wet grass. > > Even more than before, I now believe almost anything is possible. > > Now I just need to repeat this on 137.5kHz.... > > 73s > Roger G3XBM > > -- > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/g3xbm > G3XBM GQRP 1678 ISWL G11088 > -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/g3xbm G3XBM GQRP 1678 ISWL G11088 --001636499f7713ca1404931f58e8 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable No, the 500kHz TX, ATU and loop antenna are as they were a few weeks ago= Rik and I am suprised how well this all works.

The transverter (on= my website) TX produces 5W from an IRF510 and this is fed to a vertical= wire loop in the garden tuned with a capacitance decade box for maximum= loop current. The loop is supported at the house end by the aluminium pol= l used to support the 28MHz halo (about 9m above ground at highest). The= wire runs about 17m down to a tree where the far end is about 4m above gr= ound. Then it runs down to the lawn and runs back along the ground (buried= in the long grass that is wet and needs cutting) to the house. The feed= is via an upstairs bedroom window with the ATU on the bedroom table. In= all, the loop area is about 70 square metres. The wire is PVC covered 1mm= diameter wire.

The experts tell me I should raise the bottom of the loop above the gr= ound, but just resting it on the wet grass doesn't seem to be doing to= o bad. The grass is about 10cm long at the moment as it is too wet to cut= and we were away in South Africa for the last few weeks. I can increase= the wire diameter soon which will increase the loop current some 3dB.

I'd be interested to know what you believe my ERP is. My last calc= ulation came out around 2mW.

This evening I shall be back on 137.5k= Hz WSPR with the same antenna and ATU, although the ERP on 137.5kHz is muc= h lower and almost certainly not more than 100uW at very best.

73s
Roger G3XBM



On 21 Oct= ober 2010 07:47, Rik Strobbe <Rik.Strobbe@fys.kuleuven.be> wrote:<= br>
Hi Roger,
=A0
congrats with teh new ODX.
Did you improve the setup ?
I had daytime copy of your signal up= to -25dB at at night copy up to -18dB (meaning you could have reduced pow= er by another 13dB).
=A0
73, Rik=A0 ON7YD - OR7T
=A0
Van: owner-rsgb_lf= _group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens Ro= ger Lapthorn [rogerlapthorn@gmail.com]
Verzonden: woensdag 20 oktober 2010 23:24
Aan: rsgb_lf_group@blacksheep.org; GQRP@yahoogroups.com
Onderwerp: LF: New personal QRP DX record on 500kHz: 1733km

This evening, quite unexpectedly, I got a string of reports on 500kHz= WSPR from OH1LSQ in KP03sd at an astounding distance of 1733km. To me these= are amazing reports pushing my best DX on the band with just a few milliw= atts ERP to new levels.=A0 What surprises me is how well a very simple ver= tical wire loop works as a TX antenna: the wire is just 1mm diameter, with an area of around 70m square with par= t of the loop laying on the ground buried in wet grass.

Even more than before, I now believe almost anything is possible.

Now I just need to repeat this on 137.5kHz....

73s
Roger G3XBM

--
http://g3xbm-= qrp.blogspot.com/
http://www.g3xbm.co.u= k
http://www= .youtube.com/user/g3xbm
G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088



--
http://g3xbm-qrp.blogspot.com/<= br>http://www.g3xbm.c= o.uk
http://www= .youtube.com/user/g3xbm
G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088<= br> --001636499f7713ca1404931f58e8--