Return-Path: Received: from rly-mg07.mx.aol.com (rly-mg07.mail.aol.com [172.20.83.113]) by air-mg05.mail.aol.com (v125.7) with ESMTP id MAILINMG054-a264a99b487d2; Sat, 29 Aug 2009 19:07:08 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mg07.mx.aol.com (v125.7) with ESMTP id MAILRELAYINMG078-a264a99b487d2; Sat, 29 Aug 2009 19:06:48 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MhWzf-00030z-2p for rs_out_1@blacksheep.org; Sun, 30 Aug 2009 00:05:59 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MhWze-00030q-NH for rsgb_lf_group@blacksheep.org; Sun, 30 Aug 2009 00:05:58 +0100 Received: from smarthost1.mail.uk.easynet.net ([212.135.6.11]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1MhWyo-0003Qa-DO for rsgb_lf_group@blacksheep.org; Sun, 30 Aug 2009 00:05:07 +0100 Received: from bb-87-82-24-91.ukonline.co.uk ([87.82.24.91] helo=[192.168.0.4]) by smarthost1.mail.uk.easynet.net with esmtp (Exim 4.69) (envelope-from ) id 1MhWzX-0003Tb-Kb for rsgb_lf_group@blacksheep.org; Sun, 30 Aug 2009 00:05:51 +0100 Message-ID: <4A99B85F.50306@ukonline.co.uk> Date: Sun, 30 Aug 2009 00:23:11 +0100 From: Peter Dodd User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: In-Reply-To: X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Tree mixing Content-Type: text/plain; charset=ISO-8859-1; format=flowed 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=0.0 required=5.0 tests=CLICK_BELOW 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-IP: 193.82.116.20 X-Mailer: Unknown (No Version) Hi Laurence, Bit about using trees as antennas on the web. Try keying in General George O. Squier into Google and see what you get. Also in Scientific American, July 14 1919. p624 Regards Peter, G3LDO > > Sorry this is way off topic in relation to noise generation at LF/MF > but I know of one case (as I was the responsible investigating > engineer for a well known .gov dept at the time) of a tree causing non > intentional radiation as a result of mixing of 45Mhz TV signals from > Old Meldrum and a nearby "lowband" FM transmitter in Aberdeenshire - > the resultant non linear (arent they all) mixing process from this > Horse Chestnut tree (and it was the only one in the line of fire) > caused wobbly FM interference to a "fixed High band service" - > > the Tree in question was about 5 miles from the TV transmitter on a > ridge and a couple from the VHF transmitter. The interfered with rx > source was some 100m from the Chestnut tree - It was confirmed that > the interference was coming from the mid section about 5 metres from > ground level - a case of the Bark being worse than the byte. Ill > leave you to guess how I cleared the problem. > > Its the only one and only kind I came across with during my career and > I couldnt really believe what the test equipment was showing - but it > was - we didnt go interalia the causes and bio-causes of such an > effect but it did exist - honest gov. > > youll know my respect for the globally dispersed Acacia tree and how > marvellous it is as enhancer of LF signals wrt probes - so perhaps the > trees speak more than we really think at RF... > > Laurence > > With Windows Live, you can organize, edit, and share your photos. > Click here.