Return-Path: Received: from rly-dd10.mx.aol.com (rly-dd10.mail.aol.com [172.19.141.157]) by air-dd10.mail.aol.com (v124.15) with ESMTP id MAILINDD102-ba14a8e6d36214; Fri, 21 Aug 2009 05:47:36 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dd10.mx.aol.com (v124.15) with ESMTP id MAILRELAYINDD103-ba14a8e6d36214; Fri, 21 Aug 2009 05:47:35 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MeQhQ-0001eH-9V for rs_out_1@blacksheep.org; Fri, 21 Aug 2009 10:46:20 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MeQhP-0001e8-TP for rsgb_lf_group@blacksheep.org; Fri, 21 Aug 2009 10:46:19 +0100 Received: from smtp.qtxt.dns-iol.com ([195.200.78.13]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1MeQgh-0001XG-CP for rsgb_lf_group@blacksheep.org; Fri, 21 Aug 2009 10:45:36 +0100 Received: (qmail 26319 invoked by uid 507); 21 Aug 2009 11:45:58 +0200 Received: from mix-dijon-115-3-191.w193-248.abo.wanadoo.fr (HELO JR) (john.rabson@numeo.fr@193.248.40.191) by smtp.qtxt.dns-iol.com with SMTP; 21 Aug 2009 11:45:58 +0200 Message-ID: <200908211146220375.101A566B@smtp2.numeo.fr> In-Reply-To: <002901ca21bb$ba45ad90$0301a8c0@mal769a60aa920> References: <002e01ca2057$32c9a5c0$0900a8c0@AM> <4A8B9246.29046.10FABD@dave.davesergeant.com> <20090819130355.252210@gmx.net> <4D0A429582694836812C0FB6FDCADEDD@mjusamsung> <002901ca21bb$ba45ad90$0301a8c0@mal769a60aa920> X-Mailer: Courier 3.50.00.09.1098 (http://www.rosecitysoftware.com) (P) Date: Fri, 21 Aug 2009 11:46:22 +0200 From: "John RABSON" To: rsgb_lf_group@blacksheep.org Mime-Version: 1.0 X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: Re: Tree noise Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable 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=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-AOL-IP: 193.82.116.20 On 20/08/2009 at 18:29 mal hamilton wrote: [ ... ] >Serious LF/MF operators should look for a QTH out in the clear avoiding= =20 >serious obstacles like trees and close in buildings. Why struggle to=20 >reinvent the wheel=20 Because it is a challenge and great fun. And not everyone is able to move= to an ideal location. Also you might find something new. =20 When it was announced that the UK was likely to get an LF allocation (and= subsequently did) I spent some time in a major technical library looking= at textbooks on LF radio. There weren't many - they didn't even have a= copy of Watt - and everything they had dealt with physically large antenn= a systems and high power transmitters. There was nothing even remotely ap= propriate to the situations encountered by amateurs. =20 We have had to exercise a great deal of ingenuity to get where we are, whi= ch is in keeping with the philosophy of amateur radio (and its definition= in international law). =20 To cite just two examples of this ingenuity: transmitting loops seem to ha= ve been almost unknown to the old-time professionals, and some of the low= data rate systems we have been experimenting with would have been impract= icable then. John F5VLF