Return-Path: Received: from mtain-db12.r1000.mx.aol.com (mtain-db12.r1000.mx.aol.com [172.29.64.96]) by air-mf07.mail.aol.com (v129.4) with ESMTP id MAILINMF074-8bf44ca84eae2d3; Sun, 03 Oct 2010 05:36:46 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-db12.r1000.mx.aol.com (Internet Inbound) with ESMTP id C98FE380000B3; Sun, 3 Oct 2010 05:36:44 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1P2KyH-0004WK-V1 for rs_out_1@blacksheep.org; Sun, 03 Oct 2010 10:35:05 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1P2Ky7-0004W9-KW for rsgb_lf_group@blacksheep.org; Sun, 03 Oct 2010 10:34:55 +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 1P2Ky7-0007Xh-2T for rsgb_lf_group@blacksheep.org; Sun, 03 Oct 2010 10:34:57 +0100 Received: from paranoid.lipkowski.org (localhost [127.0.0.1]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id o939YrMS015574 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sun, 3 Oct 2010 11:34:53 +0200 Received: from localhost (sq5bpf@localhost) by paranoid.lipkowski.org (8.13.7/8.13.6/Submit) with ESMTP id o939Yr4N015571 for ; Sun, 3 Oct 2010 11:34:53 +0200 X-Authentication-Warning: paranoid.lipkowski.org: sq5bpf owned process doing -bs Date: Sun, 3 Oct 2010 11:34:53 +0200 (CEST) From: Jacek Lipkowski To: rsgb_lf_group@blacksheep.org In-Reply-To: Message-ID: References: <4CA5E86D.1070208@iup.uni-heidelberg.de> <6F6098420211436FABB78BE04E5F8FAD@JimPC> <000901cb6215$2db60550$0401a8c0@xphd97xgq27nyf> <4CA7096F.7070307@freenet.de> <25B77CFFDA13430086BE150894C4D3C3@Black> <5C71BB4133A642F7A2D06B26B567880D@Black> <65DFBC8F38CD4AF48A62C61B6BC4DCC4@Black> 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: LF: Re: DK7FC's 7th VLF kite experiment 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: 3039ac1d40604ca84eac7587 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) On Sat, 2 Oct 2010, James Moritz wrote: > [...] I think this is due to the cooling fan in the laptop cycling on > and off every minute or two, frequency modulating the soundcard clock by > several millihertz due to the changing temperature. I think if this > instability could be eliminated, the SNR would be improved by some dBs. > [...] in one of my laptops (lattitude d610) i just turn on the fan via acpi. in the other laptop (lattitude e4300) it just runs continiously when i run Spectrum Lab anyway. this is under linux, but there is probably some software to control the fan under windows too. it is also good to change the max sleep state that the devices will go into - turning off powersaving features cuts the sound card spurs very well. it is also good to turn on the laptop one hour before transmission, so that it reaches thermal stability VY 73 Jacek / SQ5BPF