Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-md01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 263613800009F; Fri, 6 Jan 2012 05:39:29 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Rj7C4-00028d-1q for rs_out_1@blacksheep.org; Fri, 06 Jan 2012 10:38:40 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Rj7C3-00028U-L5 for rsgb_lf_group@blacksheep.org; Fri, 06 Jan 2012 10:38:39 +0000 Received: from mailout-de.gmx.net ([213.165.64.22]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1Rj7C1-0004QQ-2H for rsgb_lf_group@blacksheep.org; Fri, 06 Jan 2012 10:38:39 +0000 Received: (qmail invoked by alias); 06 Jan 2012 10:38:30 -0000 Received: from p4FD0A3F8.dip.t-dialin.net (EHLO Clemens04) [79.208.163.248] by mail.gmx.net (mp066) with SMTP; 06 Jan 2012 11:38:30 +0100 X-Authenticated: #17214767 X-Provags-ID: V01U2FsdGVkX1+CPHFmvYWCrIJCH7epGBL+ImltBvw7nOPqsXz2Os H+hXyOLZ2FVqcA Message-ID: <012601cccc5f$54f12130$1502a8c0@Clemens04> From: "Clemens Paul" To: References: <008301ccc97c$51d9fcf0$0401a8c0@xphd97xgq27nyf>, ,<003501ccca06$6bdef490$0401a8c0@xphd97xgq27nyf> <4F02F9EA.1090101@iup.uni-heidelberg.de> <004601ccca20$8aa7d1c0$0401a8c0@xphd97xgq27nyf> <00fc01ccca65$47277e60$1502a8c0@Clemens04> <00d901ccca69$1f897260$0401a8c0@xphd97xgq27nyf> <024c01cccad1$3c099ba0$1502a8c0@Clemens04> <001901cccad5$bff43840$0401a8c0@xphd97xgq27nyf> <017301cccb22$75f61590$1502a8c0@Clemens04> <8E87C709471544DAB8BEACCCBC282F74@JimPC> Date: Fri, 6 Jan 2012 11:38:13 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3664 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3664 X-Y-GMX-Trusted: 0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: Re: Re: Loop RX Antennas 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=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-SCOLL-SCORE: 0:2:482871520:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d60554f06cf611070 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hello Jim, interesting points! I should have better talked of *system* noise figure instead of *RX* NF. With your IC-718's NF of 35dB you would need a preamp with a gain of 20dB and a NF of 1dB to reach a 15dB system NF. Are there such preamp designs around somewhere? > ...in practice it is fairly easy to hear the band noise with a 1m^2 > loop at 136k... >...Measurements here under quiet, daylight wintertime conditions >indicate a field strength as low as 60nV/m per sqrt(Hz)... It would be interesting to know if, resp. how much the noise at Mal's location could be lower than at your location at 137kHz. 73 Clemens DL4RAJ ----- Original Message ----- From: "James Moritz" To: Sent: Thursday, January 05, 2012 10:33 PM Subject: LF: Re: Loop RX Antennas