Return-Path: Received: (qmail 27099 invoked from network); 27 Mar 2003 15:09:24 -0000 Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 27 Mar 2003 15:09:24 -0000 Received: (qmail 8059 invoked from network); 27 Mar 2003 15:09:16 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 27 Mar 2003 15:09:16 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.14) id 18yYzY-0006JH-PW for rsgb_lf_group-outgoing@blacksheep.org; Thu, 27 Mar 2003 15:08:32 +0000 Received: from [165.212.11.112] (helo=cmsrelay03.mx.net) by post.thorcom.com with smtp (Exim 4.14) id 18yYzT-0006J4-1t for rsgb_lf_group@blacksheep.org; Thu, 27 Mar 2003 15:08:27 +0000 Received: from uadvg131.cms.usa.net (HELO localhost) (165.212.11.131) by cmsoutbound.mx.net with SMTP; 27 Mar 2003 15:07:53 -0000 Received: from usa.net [213.217.175.81] by uadvg131.cms.usa.net (ASMTP/dibene@usa.net) via mtad (C8.MAIN.2.05) with ESMTP id 194HcAPHz0116M31; Thu, 27 Mar 2003 15:07:52 GMT Message-ID: <3E831377.2030500@usa.net> Date: Thu, 27 Mar 2003 16:06:31 +0100 From: "Alberto di Bene" User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.0.2) Gecko/20030208 Netscape/7.02 X-Accept-Language: en-us, en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <005901c2f3c7$84a766c0$687a37c0@w2ksn> <3E82234A.1080709@usa.net> <001c01c2f417$ffdf3ac0$687a37c0@w2ksn> Subject: LF: Re: VLF signals Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-12.4 required=5.0tests=REFERENCES,USER_AGENT_MOZILLA_UAversion=2.51 X-Spam-Checker-Version: SpamAssassin 2.51 (1.174.2.5-2003-03-20-exp) X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rsgb_lf_group-outgoing@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false Stewart and Matti, thanks again for your answers. Thanks also to Alan Melia who, among other info, suggested me to browse the Web site of Renato, http://www.vlf.it who has a list of the stations on that part of the spectrum. I found the origin of those straight lines. The culprit is the UPS of my PC. Apparently, to guarantee the exactness of the generated 50 Hz in absence of the mains, it has a quartz oscillator, from which also the switching frequency is derived. Upon suggestion of Claudio IK2PII, I listened to the "cloudy" signal using a W&G Selektiver Pegelmesser, and, among pseudo-white noise, it is possible to hear a faint RTTY-sounding signal. The 15625 peak, as suggested by Stewart, is there within just a small fraction of an Hertz. When the TV upstairs in my house is on, the peak is very pronounced. If I switch off my TV, I still see a reduced peak, which with most probability is coming from the house of the neighbours (50 meters from mine). I can even watch when they change channel, from the slight discontinuity in that signal... 73 Alberto I2PHD