Return-Path: Received: from rly-mf03.mx.aol.com (rly-mf03.mail.aol.com [172.20.29.173]) by air-mf09.mail.aol.com (v125.7) with ESMTP id MAILINMF091-9504af69c32319; Sun, 08 Nov 2009 05:24:03 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mf03.mx.aol.com (v125.7) with ESMTP id MAILRELAYINMF036-9504af69c32319; Sun, 08 Nov 2009 05:23:49 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1N74v8-0004su-M8 for rs_out_1@blacksheep.org; Sun, 08 Nov 2009 10:22:54 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1N74v8-0004sl-7J for rsgb_lf_group@blacksheep.org; Sun, 08 Nov 2009 10:22:54 +0000 Received: from cavuit02.kulnet.kuleuven.be ([134.58.240.44]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1N74v6-0003hK-2g for rsgb_lf_group@blacksheep.org; Sun, 08 Nov 2009 10:22:53 +0000 Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 98A9851C002 for ; Sun, 8 Nov 2009 11:22:42 +0100 (CET) Received: from webmail6.cc.kuleuven.be (webmail6.cc.kuleuven.be [134.58.242.53]) by smtps02.kuleuven.be (Postfix) with ESMTP id 7ED7BF3862 for ; Sun, 8 Nov 2009 11:22:42 +0100 (CET) Received: by webmail6.cc.kuleuven.be (Postfix, from userid 48) id 43A9618056; Sun, 8 Nov 2009 11:22:42 +0100 (CET) Received: from 12.168-240-81.adsl-dyn.isp.belgacom.be (12.168-240-81.adsl-dyn.isp.belgacom.be [81.240.168.12]) by webmail6.kuleuven.be (Horde MIME library) with HTTP; Sun, 08 Nov 2009 11:22:42 +0100 Message-ID: <20091108112242.uuglokktzi8kw0oc@webmail6.kuleuven.be> Date: Sun, 08 Nov 2009 11:22:42 +0100 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" References: <9afca2640910310528p4f07557aifdc0557a68bfeff8@mail.gmail.com> <004501ca5a35$30eff840$0900a8c0@lark> <4F89D5F0D43E42F9B344F909CACE0ECD@JimPC> In-Reply-To: <4F89D5F0D43E42F9B344F909CACE0ECD@JimPC> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Internet Messaging Program (IMP) H3 (4.1.2) X-Originating-IP: 81.240.168.12 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: Re: 500kHz attenuation graphs? Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes"; format="flowed" 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=TO_ADDRESS_EQ_REAL 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-IP: 193.82.116.20 X-Mailer: Unknown (No Version) Dear Alan, Jim, over the 420km G4JNT-OR7T path there is a +/-20dB day/night difference 73, Rik ON7YD - OR7T Quoting James Moritz : > Dear Alan, LF Group, > > G3NYK wrote: >> Generally at LF the skywave starts to equal or exceed the >> groundwave strength at ranges exceeding 700km. It may be a little less >> that >> that at 500k. > > ...And yet, when I watch the signal level of G4JNT's WSPR beacon at night, I > see short duration deep fades of 20 - 30 dB quite often, and sometimes > enhancements over the daytime level of several dB also. During the day, the > signal level shows very little variation. So even at a distance of about > 120km, it would seem the ground wave an sky wave strengths must be > comparable, in order to produce the fades. > > Cheers, Jim Moritz > 73 de M0BMU > > >