[From nobody Thu Jul 3 13:43:05 2003 Return-Path: <majordom@post.thorcom.com> Received: from post.thorcom.com ([212.172.148.70]) by immta1.bellatlantic.net (InterMail vM.4.01.02.27 201-229-119-110) with ESMTP id <20001103225359.VSQJ1441.immta1.bellatlantic.net@post.thorcom.com> for <akestelo@bellatlantic.net>; Fri, 3 Nov 2000 17:53:59 -0500 Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 13rpcr-0000gW-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 03 Nov 2000 22:47:57 +0000 Received: from imo-r11.mx.aol.com ([152.163.225.65] helo=imo-r11.mail.aol.com) by post.thorcom.com with esmtp (Exim 3.16 #1) id 13rpcp-0000gP-00 for rsgb_lf_group@blacksheep.org; Fri, 03 Nov 2000 22:47:56 +0000 Received: from MarkusVester@aol.com by imo-r11.mx.aol.com (mail_out_v28.32.) id l.71.817b23f (4414) for <rsgb_lf_group@blacksheep.org>; Fri, 3 Nov 2000 17:47:20 -0500 (EST) From: MarkusVester@aol.com Message-ID: <71.817b23f.27349a77@aol.com> Date: Fri, 3 Nov 2000 17:47:19 EST Subject: LF: Fieldstrength at sunrise To: rsgb_lf_group@blacksheep.org MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_71.817b23f.27349a77_boundary" X-Mailer: Windows AOL sub 68 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: <majordom@post.thorcom.com> X-Mozilla-Status2: 00000000 --part1_71.817b23f.27349a77_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Hello Alan, hello group, the typical fieldstrength maximum and subsequent dip around sunrise is a very regular feature of ionospheric LF-signals. If it were just a coherent addition of two signals with slowly variing phase lag, I would expect different patterns depending on a random initial path length difference, and a time-reversed maximum-after-minimum behaviour would seem just as likely. This leads me to believe it is rather a quasioptical focusing-mirror effect, caused by the decreasing altitude of the reflecting ionospheric layers at sunrise. Focus and dip would then be essentially frequency-independent. This approach may be a bit simplistic, but what do you think? 73 de Markus, DF6NM --part1_71.817b23f.27349a77_boundary Content-Type: image/gif; name="DAYNIGHT.GIF" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="DAYNIGHT.GIF" R0lGODdhgAKgAIAAAAAAAP///ywAAAAAgAKgAAAC/oSPqcvtD6OctNqLs968+w+G4kiW5omm 6sq27gvH8kzX9o3n+s73/g8MCofEovGITCqXzKbzCY1Kp9Sq9YrNarfcrvcLDovH5LL5jE6r 1+y2+w2Py+f0uv2Oz+v3/L7/DxgoOEhYaHiImKi4yNjoiBMQKRnAIIkQqYD5uMnZGTMJmqlp YHlQ6omaqgoySkp5Sdkq+7pau9Xqmgt7CoDbGws6afvhO/uboOk7vCzFe/z8G2xKOx0dTM2M UUyNiZuMnR3eJFwNPfu6jQwufpGuC+2qzD5vRK77nVkOq06v4W4OTl6/gUC60cIHT5TCfQQt /Lu2sKHEgugq3ls37Ro2/oETF7jTuBFjx5E0EJo8SA5kSJIRvKHkx5ClzJIvT2ZEGPPdTI8a 9elMuDPoinMWgeL0CVSoNV7KjCl9moLou3M/E3KEijWrDpdFl576V1Wr2LE1PoZkGnAl2bVs 27p9Czeu3Ll069q9izev3r18+/r9Cziw4MGECxs+jDix4sVhVDp+DDmy5MmUK1u+jDmz5s2c O3sWyfjI59GkS5s+jTq16tWaQxdhDTu27Nm0a9vu7NrH7d28e/v+DRxz7rLBixs/jjz56uEv UKMY5WzIVemgVUS3Xp15FdIw5Nn7YXB6j2/ZSbxscV17FO4zxC/d0TQ9/HXyR6Qdako9lM85 /uo/+P5JeQD2B4F7/ohkYAZq6feaZ+OVN8GAUUGoDoXYRZggBQJaWAFGHDIYYGsUmRAKiRny dGIIKUbDioYfFujAiiCeIKIQ/okg4YH23ajii6L4eEk7MiLT0ow2XIbEkB6UqA2QLjoZIY4r QqkkhUoaqeBkTFy5Y4JcdsijQ1D+Z+GXUzqEJXZabjnmhOmFaSKXXxY4XZswRSlkmuatyaad LqTkJytwEvmndyW4R2WgWFL2xJw0DVqolYqKyc1z1dk5qX6VOeFoe2dluqR8nW6Q446VCKqn kI/l51U9oDZ3KaQsfPfqgbJmWSmOqWLoWE4VlupprbNmyGR/tz53/ueEvRwqLGGrEvoksMpy 2qa06FXULJ4/DiVstn89Cy2pxdLo7bQ9HttBfKNqSGezwJi46009RSTluOmWa6ma+G64boxP mueriruCG66+x6K7Fb679JsUmdn6iHA+9Pa4aK+nEmctw5HeYC2G4q57pZwxvqrwWpH5ywNE YSVZcrRAKtpxkcTIyK+prkk2coMx69ayrZLG+fKeHA6dac878XkxdT/uTNMSpWq8LbvkCtik lIYx+h8RBqoMidFCQxdidvsKlKiugSGds41jStMd1Bh7fdPE3G4UKsV8oZ11EBE3wDWzWkDH 9NfLNj34zALnhXOHepfct7i3jOx2u0eC/hxo5Kg42M6Ikwe+8hRbc84BSpZfvHfU6c7kXNU8 g8c2irc4CTqaKCqc1qRm/ryJbKTyDDeurWfhqL2h14ws353e3pJyyi+/9oP7Nd7M1NVSCiqE x2PaLvPaw2ausc9X8rsSo1ujzcd+El15taBtz75q1qXcO6ouxw+mDMJ7JOiQL88pMvjt/08w CaiEGAmj373Ud78jGYtszPoQAuvmuNzFbn5MM2DnRNOt8LWNd2CzlHhgJqcqLSKBkQrf+Oj0 PVhNUHXUOWGOSBZCHQ2ChPOZV9ssOLyu0dAfopHXsHJFrnvxsA871NvSNCi/RuHQfyu84HiM N7omgmlt+7tD/hGVRkGEnXBq4ruiE5+YvMgBI4pVWuJ6pJiycyExYF30HBK3SEDqFW1papKh H7yYhHJZjFpcgB4Wzbckh9WRhXbA45bshy0/rq4xNgRPl84kwNKhsElmLCAcCQerSDbyUWIg 2xrt5yYrUTKDVUyDIaO3wQN+ck9kcOApD/dDjlBRYwer5NwuCR8VhnKVeRpDCF9ZvmDRLX9x 6uXf0HjGQm1OkcZrZa2YmaUFMgyZrqufG6npOWUuDnq4hIQKI2bLZWHzV0KzptPGaQXahZNX 0LxCNxcGp3DWDobVI5qrJNkFPb7Tbr/iZRs5aCgwQpFyoxrUPh120Dx6K6GGkyMw/omDQX+C MlqPPJdC8enLC6VQjQ993zg2OdFR2g6jGG0gQxvlwWReC6TX4tRAL5m+ggbvpO8pRAbPuMQB wsul7Cwp/r4W0/N5raNzoOU6xRTRdsqMpz4j6S3z98BdNuKZRzXn85TasCQBNWjfFGrIZOrT opZzo6/rCU1Dd0se0Y+ae5vlWb1AuWZUdaVYnY8wi1FDTIX1pbUo2lx5pQZZgkSgOkQnR1X5 yL/m02pkPYP+WDqrgsTDsKH6pfkUC4aYqtSU9KzrEHUDub1eFpBhfGtg8WlaO5oybBKFkSMp KE3Syk0cqMWs5NZgWp2SSbLDI+rMtChaRPg2qyxrQ2oR/sqkqnb2oCs8LhuIGtxMGveansVP Wrs5XNqC07aTfC53BcjE1sKStTCNrgQfK1c3OHd3DqVsJcX72++edkrrneIb5Ju8esFXYtuk 7Ozwy8hb1deq3k0nXXkJ4P36jh6nHLCL4ODgYC6zumrLbjPDwbkIRzIOAF4q6yB7Uf8uo4Ia zi+EO+xa3obXwndFMW53VuLb3tfFeVNxe80LNBwf4oox3i2HaZw2I+pXwW/T8R3D1OMgQ/hv Wishi3cJZJyKLckX/jGTpVNYIpdwFTSkcpVP/DgsV5jCbCGhl6sphyjXWMh9InNQgHXm2apX zV+28XZAfLQ3xTlZVg6zmAPs/uZhSGjPfObwYpts3MGyw16Ezkgh6YyyPz8az4wolpG5ZUVI R9pGhHhyUdHixkzDFbOarstX6NzoyMK1HlMFoKtfDetYy3rWtK61rW+N61zrete87rWvfw3s YAt72MQutrGPjexkK7vX8Wq2s58N7WhLe9rUrra1r43tbGt729zutre/De5wixt1a2YqWegT ixQXrDuPqJ3pHP3T8pV63FILkrbWbW+AkcIR3mDVvv8NcPrwcN70Bi+++Za0eNvH34pIN8MH N8xh5lt2pGaRxQs3Rn9n/OK52ng8Le6MlBDpICDv4L89nmpdhVwWx0D5px4ujLNM3BKiS6Q4 RRek/pWnO+YXt6LMgHhyQkkc5jfHlr03zjp9oEPpAT8PxI/udOtFneFLD/pUSF44iE890RrX eNSxnvWq5xuIYD9Px31S9rKXY+t4UOvEn370dXec7V05KtDFfnaAh13vYt+7h/PedbVTne+E f/hqWRXxmcd98WMnOtwRH2+gP37yj5d82y/19r5TPiBdH7zV9Z5Gz4O98or3+90NXvhd5Efw hQe835/L+M+/PuvxAD3GHa95zQc8860Xuud9iRuE4973b5/86W9v+K2UfvR4X37sLZ9wsiej 9LPvu/WLjwbXG5/6pdB92kuU+7jtXl7Thzzjof/oNSc+9rS/OfVJn3wC+Yl+/qnffvVRb3po ORz5vTd//QPLftdHf/7Xee0newbYfPGnfQloe3TgdsMXgAvBfOeHffLXf/lXfwJ4fOq2gKtX gBgoe+hnBh14fwRIefy3fkPnf5KngcQ3e3VQJrxHe+Gnf78Hfw1ogSAIeMdndu+3aa5Xfjeo gwKIgyPYeOOXgXznfb/HekEohCh4hM8wgYkgcWQXhc43eBtIWDtIgUzYDUn4d2NHczPIf683 hiUIe1THcjZYcyc4ej3HDV84WY7mbmwoh2dYhIFQh6pXIQknToqnhQUnEQQniIXYIvFniIk4 X4SoiI3oiI8IiZEoiZNIiZVYAgUAAAA7 --part1_71.817b23f.27349a77_boundary-- ]