Return-Path: Received: from mtain-df12.r1000.mx.aol.com (mtain-df12.r1000.mx.aol.com [172.29.64.224]) by air-mf03.mail.aol.com (v129.4) with ESMTP id MAILINMF031-8bd94cab8a0a22a; Tue, 05 Oct 2010 16:26:50 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-df12.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1EA69380000F8; Tue, 5 Oct 2010 16:26:49 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1P3E4c-0007kE-Ui for rs_out_1@blacksheep.org; Tue, 05 Oct 2010 21:25:18 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1P3E4c-0007k5-It for rsgb_lf_group@blacksheep.org; Tue, 05 Oct 2010 21:25:18 +0100 Received: from 113-mo2-8.acn.waw.pl ([62.121.95.113] helo=paranoid.lipkowski.org) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1P3E4Z-0001R3-Tk for rsgb_lf_group@blacksheep.org; Tue, 05 Oct 2010 21:25:18 +0100 Received: from paranoid.lipkowski.org (localhost [127.0.0.1]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id o95KPDJo026382 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Tue, 5 Oct 2010 22:25:13 +0200 Received: from localhost (sq5bpf@localhost) by paranoid.lipkowski.org (8.13.7/8.13.6/Submit) with ESMTP id o95KPDEh026379 for ; Tue, 5 Oct 2010 22:25:13 +0200 X-Authentication-Warning: paranoid.lipkowski.org: sq5bpf owned process doing -bs Date: Tue, 5 Oct 2010 22:25:13 +0200 (CEST) From: Jacek Lipkowski To: rsgb_lf_group@blacksheep.org In-Reply-To: <4CAB5DA6.6060805@iup.uni-heidelberg.de> Message-ID: References: <4CA9BDE0.4000601@iup.uni-heidelberg.de> <646839.20132.qm@web111910.mail.gq1.yahoo.com> <4CAA4521.6070301@iup.uni-heidelberg.de> <242345.444.qm@web111918.mail.gq1.yahoo.com> <4CAB5DA6.6060805@iup.uni-heidelberg.de> MIME-Version: 1.0 X-Spam-Score-sq5bpf: -2.601 () BAYES_00,SPF_HELO_PASS,SPF_PASS X-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: VLF: Inspire VLF-3 receiver + samole rate drift problems Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed 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: 3039ac1d40e04cab8a0862d4 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) Danielle, Like Stefan said - try to put a simple e-probe antenna on the roof. i use a PA0RDT mini-whip modified for better low frequency response with 50cm of wire as the antenna, and some lowpass filtering/amplification in the shack. so far the results were great. The E-field from powerlines is screened out by the buildings themselves, while the H-field is not. So in the city you will get less interference from an E-probe on the roof. Remember the lowpass filtering - whatever you do, try to connect a simple lm386 based amp to each stage, if you hear radio stations, then you need more filtering :) Also check if you get a line at 9kHz on the spectrogram (his is intermod from radio stations), it means more filtering is needed. Good luck Jacek / SQ5BPF