Return-Path: Received: from mtain-ma06.r1000.mx.aol.com (mtain-ma06.r1000.mx.aol.com [172.29.96.14]) by air-mf03.mail.aol.com (v129.4) with ESMTP id MAILINMF032-8bde4c125e5a382; Fri, 11 Jun 2010 12:03:38 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-ma06.r1000.mx.aol.com (Internet Inbound) with ESMTP id F1F2438000169; Fri, 11 Jun 2010 12:03:35 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ON6gE-0001fl-1N for rs_out_1@blacksheep.org; Fri, 11 Jun 2010 17:02:02 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ON6gD-0001fc-Ka for rsgb_lf_group@blacksheep.org; Fri, 11 Jun 2010 17:02:01 +0100 Received: from out1.ip01ir2.opaltelecom.net ([62.24.128.237]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1ON6gA-0007Ir-S2 for rsgb_lf_group@blacksheep.org; Fri, 11 Jun 2010 17:02:01 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AlAKANb6EUxOk8bA/2dsb2JhbACHZIpUMIwTcb9ZhRgE X-IronPort-AV: E=Sophos;i="4.53,404,1272841200"; d="scan'208";a="313379396" Received: from unknown (HELO xphd97xgq27nyf) ([78.147.198.192]) by out1.ip01ir2.opaltelecom.net with SMTP; 11 Jun 2010 17:01:50 +0100 Message-ID: <003a01cb097f$640755d0$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <002401cb096b$7d950560$0401a8c0@xphd97xgq27nyf> Date: Fri, 11 Jun 2010 17:01:42 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: LF/VLF Content-Type: text/plain; charset="iso-8859-1" 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=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-global-disposition: G x-aol-sid: 3039ac1d600e4c125e57497c X-AOL-IP: 193.82.116.20 Warren I have not found that to be the case at this qth. Loops are not affected by trees because there is nothing being radiated to be affected whereas the big signals from verticals are affected to some degree but most of the rf escapes to DX locations I am not aware of any commercial LF or MF station using loops. Verticals large voltages small current , loops no voltage but large current causing big losses, especially whey one hears about loops being wound around big lossy leafy trees. de mal/g3kev ----- Original Message ----- From: "Warren Ziegler" To: Sent: Friday, June 11, 2010 3:31 PM Subject: Re: LF: LF/VLF Mal, On 137kHz loops here produce 1W ERP for each 400 Watts of transmitter output. I recall someone posting here from the U.K. that his vertical on 137 produced 700 mW ERP with 650 Watts transmitter output so sometimes loops are superior. -- 73 Warren K2ORS WD2XGJ WD2XSH/23 WE2XEB/2 WE2XGR/1 On Fri, Jun 11, 2010 at 10:21 AM, Laurence KL7UK wrote: > > > Mal - are you saying small lambda loops are ineffective for dx working at > LF, say 137Khz? (where within practical verticals give poorer performance > in wooded areas....or arent feasible). > > Past results would not concur; Small backgarden loops producing around 3W > ERP (on a good day!) have been repeatably seen at >12,000kms - so I beg to > differ. > > Cheers > > ________________________________ > From: g3kevmal@talktalk.net > To: rsgb_lf_group@blacksheep.org > Date: Fri, 11 Jun 2010 14:39:17 +0100 > Subject: LF: LF/VLF > > All > Forget about loops, ground rod induction etc if you want to radiate a dx > signal.The average person could shout and be heard further. A mechanical > alert/fire siren can be heard several miles away by ear. > For serious distance DX on vlf a vertical configured antenna is the only > solution, ie loaded inv L, T ant and some insulated ground radials as long > as possible. > one earth spike at the base of the vertical drop wire connected to radials. > This is the basic approach and can be fine tuned later once you are making > progress and being heard/seen a few hundred kilometres away. > 73 de mal/g3kev > > > ________________________________ > Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. > Learn more.