Return-Path: Received: from rly-mg05.mx.aol.com (rly-mg05.mail.aol.com [172.20.83.111]) by air-mg07.mail.aol.com (v121_r4.4) with ESMTP id MAILINMG071-a1549a8711c3ba; Fri, 27 Feb 2009 18:03:24 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mg05.mx.aol.com (v121_r4.4) with ESMTP id MAILRELAYINMG057-a1549a8711c3ba; Fri, 27 Feb 2009 18:02:58 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1LdBgG-0001RF-2o for rs_out_1@blacksheep.org; Fri, 27 Feb 2009 22:59:44 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1LdBgF-0001R6-Mi for rsgb_lf_group@blacksheep.org; Fri, 27 Feb 2009 22:59:43 +0000 Received: from vms173005pub.verizon.net ([206.46.173.5]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1LdBgC-0004vC-4V for rsgb_lf_group@blacksheep.org; Fri, 27 Feb 2009 22:59:43 +0000 Received: from DR2 ([71.184.212.10]) by vms173005.mailsrvcs.net (Sun Java(tm) System Messaging Server 6.3-7.04 (built Sep 26 2008; 32bit)) with ESMTPA id <0KFQ00I1IYIS72Z4@vms173005.mailsrvcs.net> for rsgb_lf_group@blacksheep.org; Fri, 27 Feb 2009 16:59:17 -0600 (CST) Message-id: From: "dave.riley3" To: References: , <4A11BD1B67394BDD9B3001D8F176B76F@DR2> <49A82D84.827.1398FD9@mike.dennison.ntlworld.com> Date: Fri, 27 Feb 2009 17:59:18 -0500 MIME-version: 1.0 X-Priority: 3 X-MSMail-priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Karma: unknown: X-Spam-Score: 3.4 (+++) X-Spam-Report: autolearn=disabled,FORGED_MUA_OUTLOOK=3.36 Subject: Re: LF: Re: LF Antennas - back to basics Content-type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original 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=1.6 required=5.0 tests=FORGED_MUA_OUTLOOK 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 Howdy Mike, Well, I am grateful for the 2 nulls as there is little or no activity in those directions thus making for some gain in the favored directions ( NE-SW ) and lowering noise from the sides... As far as lowering the R of this loop, I plan soon to parallel the loop with a second one tuned in the near field, that outta run the 'R' down some more... In the meanwhile an e-probe way out in the woods helps to cancel some residual noise... In the LowFer days 160-180 khz. I found that the AC neutral was a decent enuf ground. The idea of having above ground radials with an inductance in series with their common point makes for lower looses as well, but then again, one allows the local 'E' field to become part of the 'loop' while a complete loop shunts the local E fields and produces far less lethan voltages.. Gudday from Dave @ WD2XSH/17 ----- Original Message ----- From: "Mike Dennison" To: Sent: Friday, February 27, 2009 1:14 PM Subject: Re: LF: Re: LF Antennas - back to basics > Dave Riley write about loop antennas: >> As for the CONS, well I just don't think of any... Somebody?? >> > There are two 'cons' that I can think of. One is the weight of the > low-loss wire required. This would cause a problem in my own case as > local restrictions lead me to use a fairly fragile mast. The other is > directivity in the form of two sharp nulls. > > I have used a loop in the past and for a short while held the 73kHz > distance record using it. However, after some comparitive tests, I > opted for a Marconi which at that frequency had similar 'gain' but > was almost omnidirectional. > > In all other respects you are, of course, right. > > Mike, G3XDV > ========== >