Return-Path: Received: (qmail 3812 invoked from network); 17 Nov 2004 15:31:55 -0000 Received: from unknown (HELO ptb-spamcore02.plus.net) (192.168.71.3) by ptb-mailstore02.plus.net with SMTP; 17 Nov 2004 15:31:55 -0000 Received: from mailnull by ptb-spamcore02.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1CURly-0008bT-Fr for dave@picks.force9.co.uk; Wed, 17 Nov 2004 15:31:07 +0000 Received: from [192.168.67.1] (helo=ptb-mxcore01.plus.net) by ptb-spamcore02.plus.net with esmtp (Exim 4.32; FreeBSD) id 1CURlx-0008bJ-Gf for dave@picks.force9.co.uk; Wed, 17 Nov 2004 15:31:05 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore01.plus.net with esmtp (Exim 4.30; FreeBSD) id 1CURmj-0008Wg-HR for dave@picks.force9.co.uk; Wed, 17 Nov 2004 15:31:53 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1CURmK-0007Qy-Vy for rs_out_1@blacksheep.org; Wed, 17 Nov 2004 15:31:28 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1CURmK-0007Qp-IS for rsgb_lf_group@blacksheep.org; Wed, 17 Nov 2004 15:31:28 +0000 Received: from smarthost4.mail.uk.easynet.net ([212.135.6.14]) by relay.thorcom.net with esmtp (Exim 4.41) id 1CURm9-00008W-M9 for rsgb_lf_group@blacksheep.org; Wed, 17 Nov 2004 15:31:28 +0000 Received: from apache3-wm.uk.easynet.net ([212.135.6.54]) by smarthost4.mail.uk.easynet.net with esmtp (Exim 4.10) id 1CURm9-000P2M-00 for rsgb_lf_group@blacksheep.org; Wed, 17 Nov 2004 15:31:17 +0000 Received: from www by apache3-wm.uk.easynet.net with local (Exim 3.36 #1) id 1CURm9-0006ZD-00 for rsgb_lf_group@blacksheep.org; Wed, 17 Nov 2004 15:31:17 +0000 Received: from 205.172.40.2 ([205.172.40.2]) by webmail.ukonline.net (IMP) with HTTP for ; Wed, 17 Nov 2004 15:31:17 +0000 Message-ID: <1100705477.419b6ec50ba2f@webmail.ukonline.net> Date: Wed, 17 Nov 2004 15:31:17 +0000 From: captbrian To: rsgb_lf_group@blacksheep.org References: <19115558.1100686187421.JavaMail.www@wwinf3003> In-Reply-To: <19115558.1100686187421.JavaMail.www@wwinf3003> MIME-Version: 1.0 User-Agent: Internet Messaging Program (IMP) 3.2 X-Originating-IP: 205.172.40.2 X-SPF-Result: relay.thorcom.net: 212.135.6.14 is neither permitted nor denied by domain of ukonline.co.uk X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=no,TW_GV=0.077 Subject: LF: Telephone wires Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Status: No, hits=0.0 required=5.0 tests=none 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-Spam-Filtered: by PlusNet SpamCORE (v3.00) neighbours telephone wires across my garden are an upcoming hazard for me also. Why not tell phone company to take 'em away? Did they ask your permission to put 'em there? Bryan g3gvb ( In w-land this month tho' ] Quoting Lawrence Mayhead G3AQC : > > > > > > > ======================================== > Message date : Nov 17 2004, 09:20 AM > From : "OSBORN, Chris" > To : "LF Group (E-mail)" > Copy to : > Subject : LF: Loading Coils > > > > Hello LF Group > > Many thanks for all comments and advice - most interesting. > > I drilled out the wooden dowels on the loading coil and replaced > them with lengths of 15 mm plastic water pipe. > I was unable to obtain plastic rod at short notice and my XYL > wouldn't let me have her knitting needles ! > The pipe was not really rigid enough and bent slightly but was > sufficient to prove the experiment. > With this new arrangement I obtained my personal best Q of about > 250.. > > Placing the new coil in the aerial circuit made a slight improvement > to the aerial current - from about 1.2 A to 1.5 A > I would have thought that as most of the losses were in the coil a > bigger current improvement would have been achieved. > > I share my office with some young electronics engineers and was > surprised that they know very little about RF inductors or Q factor. > It must be a dying art ! > > My next improvement will be to raise the 'droopy' end of my aerial, > presently at a height of about 5 metres > Unfortunately two neighbours' telephone wires pass over my garden > where the mast was to be situated. > Any suggestions - should I go over the wires or keep well clear of > them and cut a length off the aerial ? > Presumably I can't get the phone company to move their wires !! > > 73 Chris G3XIZ > > Hi Chris, > Major losses are ground losses ! This is very difficult to overcome, buried > radials do not seem to help presumably because the lengths that most of us > can manage are too short. I have found that by far the best way if lowering > losses is to put more wire in the air. One meter of wire in the air is worth > 100m in the ground ! This extra wire does not have to be in a straight line > but it must not be too close to existing wires.So try a zig zag or radial top > hat. Do try to raise the low end also since this works against the height of > the vertical section and lowers the radiation resistance. > Best of luck Laurie. > > -- > > Whatever you Wanadoo: > http://www.wanadoo.co.uk/time/ > > This email has been checked for most known viruses - find out more at: > http://www.wanadoo.co.uk/help/id/7098.htm -- ---------------------------------------------- This mail sent through http://www.ukonline.net