Return-Path: Received: (qmail 10501 invoked from network); 17 Feb 2000 08:41:20 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by bells.core.plus.net.uk with SMTP; 17 Feb 2000 08:41:20 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12LMNT-0006PC-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 17 Feb 2000 08:33:35 +0000 Content-Transfer-Encoding: 8bit Received: from mail.cc.kuleuven.ac.be ([134.58.10.6]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12LMNQ-0006P7-00 for rsgb_lf_group@blacksheep.org; Thu, 17 Feb 2000 08:33:32 +0000 Received: from LCBD15.fys.kuleuven.ac.be (LCBD15.fys.kuleuven.ac.be [134.58.80.15]) by mail.cc.kuleuven.ac.be (8.9.3/8.9.0) with SMTP id JAA73136 for ; Thu, 17 Feb 2000 09:33:25 +0100 X-Priority: 3 X-MSMail-Priority: Normal Message-ID: <3.0.1.16.20000217103107.269f94c2@mail.cc.kuleuven.ac.be> X-Sender: pb623250@mail.cc.kuleuven.ac.be X-Mailer: Windows Eudora Pro Version 3.0.1 (16) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Date: Thu, 17 Feb 2000 10:31:07 To: rsgb_lf_group@blacksheep.org From: "Rik Strobbe" Subject: Re: LF: Re SIDs and Transatlantic In-reply-to: <3.0.6.32.20000216200202.008642e0@laatikko.saunalahti.fi> References: <000201bf7872$bb1e6740$e491883e@lvm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: At 20:02 16/02/00 +0200, OH2LX wrote: >SID effects are mainly caused by solar EM radiation >and D region effects by hard X-rays. So they travel >with about the same speed than visible light does. Vaino is right, I mixed up SID (or MDE) with the auroral effects which are caused by slower particles and occure several days after a major flare. In the past I observed enhanced propagation on 136kHz in northern directions at days when aurora was reported on VHF and also recent observations in Canada showed enhanced propagation several days after a flare. So maybe (partly) the same mechanisms are involved. Aurora reports on in DX-clusters could be used as a warning for enhanced LF propagation. 73, Rik ON7YD