Return-Path: Received: (qmail 10971 invoked from network); 14 Nov 2002 14:18:53 -0000 Received: from mx.last.plus.net (212.159.3.230) by mailstore with SMTP; 14 Nov 2002 14:18:53 -0000 Content-Transfer-Encoding: 8bit Received: (qmail 8348 invoked from network); 14 Nov 2002 13:04:20 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from post.thorcom.com (193.82.116.70) by mx.last.plus.net with SMTP; 14 Nov 2002 13:04:20 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18CJnI-0001F2-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 14 Nov 2002 13:12:28 +0000 Received: from [134.58.10.57] (helo=mail3.cc.kuleuven.ac.be) by post.thorcom.com with esmtp (Exim 4.10) id 18CJnH-0001Em-00 for rsgb_lf_group@blacksheep.org; Thu, 14 Nov 2002 13:12:27 +0000 Received: from dell-rik.fys.kuleuven.ac.be (pc-10-33-165-177.fys.kuleuven.ac.be [10.33.165.177]) by mail3.cc.kuleuven.ac.be (8.12.1/8.12.1) with ESMTP id gAEDBuZC058062 for ; Thu, 14 Nov 2002 14:11:57 +0100 Message-ID: <5.1.0.14.0.20021114135046.02a5e660@pb623250.kuleuven.be> X-Sender: pb623250@pb623250.kuleuven.be X-Mailer: QUALCOMM Windows Eudora Version 5.1 Date: Thu, 14 Nov 2002 14:18:06 +0100 To: rsgb_lf_group@blacksheep.org From: "Rik Strobbe" In-reply-to: <3DD389EE.E34C64A9@snet.net> References: <3DD35969.30941.58250D@localhost> <004801c28bb7$b2c00580$015e89d9@jackie> MIME-Version: 1.0 Subject: Re: LF: Loop vs Marconi Content-Type: text/plain; charset=us-ascii; format=flowed X-Spam-Status: No, hits=-0.5 required=5.0tests=IN_REP_TO,REFERENCES,SPAM_PHRASE_00_01version=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Hello Steve and Jay, I simulated a 15m high / 30m long loop at 1m above ground (Er=5, S=0.1mS/m) using MMAMA. Results were : >The loop is actually fairly omnidirectional - just not at 0 degrees >elevation. As you move up from 0 degrees elevation the pattern starts to >"fill in" nicely in the direction of the "nulls". The nulls are minimal at an elevation of about 30 degrees (but still -15..20dB) >Not sure, but I think you can prove this with a small receive loop while >nulling out a local broadcast station. Tilt the loop even slightly off >vertical and away goes your null in a hurry. Tilting the loop didn't change the radiation pattern (vertical polarization), but it just probably reduces the radiation resistance The above assumes not "electrical pick-up". Maybe the nulls in a RX loop get smaller when tilting the loop because the magnetic component decreases while the electric component almost remains.