Return-Path: Received: from mtain-md01.r1000.mx.aol.com (mtain-md01.r1000.mx.aol.com [172.29.96.85]) by air-dd10.mail.aol.com (v129.10) with ESMTP id MAILINDD102-86384dde5e9dab; Thu, 26 May 2011 10:07:25 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-md01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 22179380000A7; Thu, 26 May 2011 10:07:13 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QPbAt-0002W8-MB for rs_out_1@blacksheep.org; Thu, 26 May 2011 15:04:31 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QPbAt-0002Vz-9f for rsgb_lf_group@blacksheep.org; Thu, 26 May 2011 15:04:31 +0100 Received: from rhcavuit01.kulnet.kuleuven.be ([134.58.240.129] helo=cavuit01.kulnet.kuleuven.be) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QPbAq-0008U0-UN for rsgb_lf_group@blacksheep.org; Thu, 26 May 2011 15:04:31 +0100 X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-KULeuven-Scanned: Found to be clean X-KULeuven-ID: C8A1B13830B.AB863 X-KULeuven-Information: Katholieke Universiteit Leuven Received: from smtps02.kuleuven.be (smtpshost02.kulnet.kuleuven.be [134.58.240.75]) by cavuit01.kulnet.kuleuven.be (Postfix) with ESMTP id C8A1B13830B for ; Thu, 26 May 2011 16:04:18 +0200 (CEST) Received: from ICTS-S-HUB-N2.luna.kuleuven.be (icts-s-hub-n2.luna.kuleuven.be [10.112.9.12]) by smtps02.kuleuven.be (Postfix) with ESMTP id A804CF3870 for ; Thu, 26 May 2011 16:04:18 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N2.luna.kuleuven.be ([10.112.9.12]) with mapi; Thu, 26 May 2011 16:04:18 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Thu, 26 May 2011 16:00:14 +0200 Thread-Topic: 137 kHz groundwave Thread-Index: Acwbo+oyEGS3V3lFS12cB6iB/cFSEwACVJ+H Message-ID: References: <4DDE4CB5.4040803@iup.uni-heidelberg.de> In-Reply-To: <4DDE4CB5.4040803@iup.uni-heidelberg.de> Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: RE: 137 kHz groundwave Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 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-global-disposition: G x-aol-sid: 3039ac1d60554dde5e911852 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) Hello Stefan, this was discussed many (> 10) years ago and if I remind well the outcome= was that for groundwave the attenuation (in dB) is linear to the distance= (as it in with a coax cable). I believe that there exist CCIR tables about this. 73, Rik ON7YD - OR7T ________________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens Stefan Sch=E4fer [schaefer@iup.uni-heidelberg.de] Verzonden: donderdag 26 mei 2011 14:51 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: 137 kHz groundwave LF, I just sent some CQ calls on 137.71 kHz and saw the signal at about the same strength on the G4WGT grabber in 910 km, O copy. But there is no trace at all on the YO/4X1RF grabber in 1426 km (in QRSS-10). The 137 kHz groundwave seems to "stop" somewhere between these distances, maybe arround 1000km. I'm sure some of you have some better theoretical and/or practical experience about that? Another advantage of VLF,where it's "easy" to reach 2500 km and above anytime :-) 73, Stefan/DK7FC