Delivered-To: daveyxm@virginmedia.com Received: by 10.50.93.2 with SMTP id cq2csp28588igb; Thu, 12 Sep 2013 12:17:27 -0700 (PDT) X-Received: by 10.180.188.202 with SMTP id gc10mr7270883wic.3.1379013446999; Thu, 12 Sep 2013 12:17:26 -0700 (PDT) Return-Path: Received: from post.thorcom.com (post.thorcom.com. [195.171.43.25]) by mx.google.com with ESMTP id t1si4378278wia.86.1969.12.31.16.00.00; Thu, 12 Sep 2013 12:17:26 -0700 (PDT) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE dis=NONE) header.from=gmail.com Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1VKBy7-0008Rk-2N for rs_out_1@blacksheep.org; Thu, 12 Sep 2013 19:50:19 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1VKBy6-0008Rb-Db for rsgb_lf_group@blacksheep.org; Thu, 12 Sep 2013 19:50:18 +0100 Received: from mail-qe0-f46.google.com ([209.85.128.46]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1VKBy2-00074d-Uf for rsgb_lf_group@blacksheep.org; Thu, 12 Sep 2013 19:50:17 +0100 Received: by mail-qe0-f46.google.com with SMTP id x7so183365qeu.33 for ; Thu, 12 Sep 2013 11:50:13 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=bj0v+BfeJypjT8Gh6OomcYzx+83pGpDb9Trv4BUqiMY=; b=fSFhJ3ApygwPIuE9W/2u/ulpnHf/WGel1QnLPQUnvKgTsLhxcdTQGmU8IyVgWuJ/5n Mo/JTaKmm0XeHVeuMj1447ulAaJl8//vJwEwaawX5xbZgEXgWrSRVqUuVof554LUOfzN E675ZC/ufoPKb2FhU08MMRhRPDLsJsElXsnxevVDdLUA0edJQGxeDuzuYFBoglJuTVxy lCaVgFTI39kfUUsEvPJL+tZDrCtkmI+WKew+c97TalX/8b+Cntv/5qPhnEae1iu7dVDp 6YnsxsAW4AZkcDmeVWV+SLL+4lncNlq4F5hTD1K9Ba1mZ1be5L8RUd9sH/m2y/+944x3 iqsg== MIME-Version: 1.0 X-Received: by 10.49.107.105 with SMTP id hb9mr16356955qeb.74.1379011812967; Thu, 12 Sep 2013 11:50:12 -0700 (PDT) Received: by 10.229.11.138 with HTTP; Thu, 12 Sep 2013 11:50:12 -0700 (PDT) In-Reply-To: <52320980.5070806@iup.uni-heidelberg.de> References: <52320980.5070806@iup.uni-heidelberg.de> Date: Thu, 12 Sep 2013 19:50:12 +0100 Message-ID: From: Roger Lapthorn To: "rsgb_lf_group@blacksheep.org" X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Stefan, It is on our local "hill" on the 20m contour, so is a better VHF, UHF, uW QTH but the garden shape/size is less ideal for LF and MF. The loop, at present, is 1mm diameter wire running along a 2m high fence, for about 10m, then along another fence at 2m at right angles for about 5m, then a wire back along the top of the grass to the shack. I estimate loop area as around 60-80m sq, but it is far from vertical. TX power into the loop is around 12W and the measured antenna current 0.9A. My aim is to get an efficient LF/MF antenna that is not noticeable by the neighbours, HI. The earth-electrode system fully meets this criterion, but is not good enough at this QTH. If tests tonight are encouraging I will raise the loop height (and increase loop area) in the coming weeks. BTW, you were a very good signal last night on the earth-electrode antenna with signals close to 0dB S/N at times. [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.128.46 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rogerlapthorn[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 6ae5fe68d6708d1e4a9cbdf0f0af43e5 Subject: Re: LF: 630m WSPR this evening Content-Type: multipart/alternative; boundary=047d7bd75ac840eec104e63435a6 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=HTML_MESSAGE, 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 Status: O X-Status: X-Keywords: X-UID: 1931 --047d7bd75ac840eec104e63435a6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi Stefan, It is on our local "hill" on the 20m contour, so is a better VHF, UHF, uW QTH but the garden shape/size is less ideal for LF and MF. The loop, at present, is 1mm diameter wire running along a 2m high fence, for about 10m, then along another fence at 2m at right angles for about 5m, then a wire back along the top of the grass to the shack. I estimate loop area as around 60-80m sq, but it is far from vertical. TX power into the loop is around 12W and the measured antenna current 0.9A. My aim is to get an efficient LF/MF antenna that is not noticeable by the neighbours, HI. The earth-electrode system fully meets this criterion, but is not good enough at this QTH. If tests tonight are encouraging I will raise the loop height (and increase loop area) in the coming weeks. BTW, you were a very good signal last night on the earth-electrode antenna with signals close to 0dB S/N at times. I am being tempted onto 23cms and 10GHz by locals here and have further red light and IR "over the horizon" scatter tests to try, so progress on LF/MF may be interrupted. 73s Roger G3XBM On 12 September 2013 19:35, Stefan Sch=E4fer < Stefan.Schaefer@iup.uni-heidelberg.de> wrote: > ** > Hi Roger, > > Some more details please. What is the loop's cross section area. What typ= e > of wire did you use? What TX power? Will you some day try to get an anten= na > efficiency that is as good as possible for the given QTH? > Did you actually move to a QTH with even more restricted antenna > possibilities??? > I'm watching! > > 73, Stefan/DK7FC > > Am 12.09.2013 20:15, schrieb Roger Lapthorn: > > 'Recently I moved 350m east (!) to a new QTH and I've been experimenting > with 630m WSPR. > > My initial tests were with the transverter on my website feeding a pair o= f > earth-electrodes but with a shorter baseline than was possible at the old > QTH (about 12m separation). Although I managed to get reports from G, ON > and PA, it was clear that results were nowhere near as good as I obtained > at the old QTH. I am speculating that this is due to the effective spacin= g > between earth rods being much shorter and due to buried wires and pipes > criss-crossing the lawn. On RX it is working very well though and I have > copied most of the nearer Europeans on 630m WSPR. > > This afternoon I converted the earth-electrode antenna to an "in the air" > loop by disconnecting the earth rods and joining the wire ends with a wir= e > running along the top of the lawn (in the grass). The loop DC resistance = is > 0.9 ohms and it tunes sharply with about 1.7nF. Matching is via a 3C90 > step-down toroid. > > Initial encouraging reports include first spots from M0PPP, who had faile= d > to copy me before from this QTH, as well as PA3ABK/2 and G8HUH. > > If anyone else can look for me this evening I'd appreciate it. The loop i= s > not very high and can be further improved if results this evening are > encouraging. > > 73s > Roger G3XBM > > -- > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > https://sites.google.com/site/sub9khz/ > http://qss2.blogspot.com/ > http://www.youtube.com/user/g3xbm > > --=20 http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk https://sites.google.com/site/sub9khz/ http://qss2.blogspot.com/ http://www.youtube.com/user/g3xbm --047d7bd75ac840eec104e63435a6 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Hi Stefan,

It is on our l= ocal "hill" on the 20m contour, so is a better VHF, UHF, uW QTH b= ut the garden shape/size is less ideal for LF and MF.

The loo= p, at present, is 1mm diameter wire running along a 2m high fence, for abou= t 10m, then along another fence at 2m at right angles for about 5m, then a = wire back along the top of the grass to the shack. I estimate loop area as = around 60-80m sq, but it is far from vertical. TX power into the loop is ar= ound 12W and the measured antenna current 0.9A. My aim is to get an efficie= nt LF/MF antenna that is not noticeable by the neighbours, HI. The earth-el= ectrode system fully meets this criterion, but is not good enough at this Q= TH.=A0 If tests tonight are encouraging I will raise the loop height (and i= ncrease loop area) in the coming weeks.=A0 BTW, you were a very good signal= last night on the earth-electrode antenna with signals close to 0dB S/N at= times.

I am being tempted onto 23cms and 10GHz by locals here and h= ave further red light and IR "over the horizon" scatter tests to = try, so progress on LF/MF may be interrupted.

73s
Roger G3XBM




On 12 September= 2013 19:35, Stefan Sch=E4fer <Stefan.Schaefer@iup.uni= -heidelberg.de> wrote:
=20
Hi Roger,

Some more details please. What is the loop's cross section area. What type of wire did you use? What TX power? Will you some day try to get an antenna efficiency that is as good as possible for the given QTH?
Did you actually move to a QTH with even more restricted antenna possibilities???
I'm watching!

73, Stefan/DK7FC

Am 12.09.2013 20:15, schrieb Roger Lapthorn:
'Recently I moved 350m east (!) to a new QTH and I&#= 39;ve been experimenting with 630m WSPR.

My initial tests were with the transverter on my website feeding a pair of earth-electrodes but with a shorter baseline than was possible at the old QTH (about 12m separation). Although I managed to get reports from G, ON and PA, it was clear that results were nowhere near as good as I obtained at the old QTH. I am speculating that this is due to the effective spacing between earth rods being much shorter and due to buried wires and pipes criss-crossing the lawn. On RX it is working very well though and I have copied most of the nearer Europeans on 630m WSPR.

This afternoon I converted the earth-electrode antenna to an "in the air" loop by disconnecting the earth rods and joining the wire ends with a wire running along the top of the lawn (in the grass). The loop DC resistance is 0.9 ohms and it tunes sharply with about 1.7nF. Matching is via a 3C90 step-down toroid.

Initial encouraging reports include first spots from M0PPP, who had failed to copy me before from this QTH, as well as PA3ABK/2 and G8HUH.

If anyone else can look for me this evening I'd appreciate it. The loop is not very high and can be further improved if results this evening are encouraging.

73s
Roger G3XBM

--



--
--047d7bd75ac840eec104e63435a6--