Return-Path: Received: from mtain-ma03.r1000.mx.aol.com (mtain-ma03.r1000.mx.aol.com [172.29.96.11]) by air-df04.mail.aol.com (v127_r1.1) with ESMTP id MAILINDF041-5eee4babf3ab1b9; Thu, 25 Mar 2010 19:37:15 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-ma03.r1000.mx.aol.com (Internet Inbound) with ESMTP id DAD5A380000F8; Thu, 25 Mar 2010 19:37:13 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Nuwat-0003fk-LO for rs_out_1@blacksheep.org; Thu, 25 Mar 2010 23:36:07 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Nuwat-0003fb-01 for rsgb_lf_group@blacksheep.org; Thu, 25 Mar 2010 23:36:07 +0000 Received: from mailout.toya.net.pl ([217.113.224.27] ident=postfix) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Nuwap-0002AF-VM for rsgb_lf_group@blacksheep.org; Thu, 25 Mar 2010 23:36:06 +0000 Received: from mail.toya.net.pl (localhost.localdomain [127.0.0.1]) by mail.toya.net.pl (Postfix) with ESMTP id ED6B420000076 for ; Fri, 26 Mar 2010 00:36:02 +0100 (CET) Received: from [192.168.1.103] (unknown [10.3.148.9]) (Authenticated sender: unimlyn) by mail.toya.net.pl (Postfix) with ESMTPSA id DA64620000068 for ; Fri, 26 Mar 2010 00:36:02 +0100 (CET) Message-ID: <4BABF362.8000703@toya.net.pl> Date: Fri, 26 Mar 2010 00:36:02 +0100 From: =?UTF-8?B?UGlvdHIgTcWCeW5hcnNraQ==?= User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <4B9FD008.2070607@abelian.org> <4BAAA535.4050401@toya.net.pl> <4BAB1E85.1060304@abelian.org> <4BABA614.4030303@abelian.org> In-Reply-To: <4BABA614.4030303@abelian.org> X-AV-Checked: ClamAV using ClamSMTP X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Ionospheric VLF propagation Content-Type: text/plain; charset=UTF-8; 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=none 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: 3039ac1d600b4babf3a94ff5 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) Paul Nicholson wrote: > ..... > I found in another paper a formula for field strength at VLF. > It uses Legendre functions to model propagation in terms of > cavity modes, combined with an empirical model of attenuation. > Formula is too long to post here but the paper is at > > http://dspace.mit.edu/bitstream/handle/1721.1/16973/53712465.pdf?sequence=1 > > > Maybe I will program this if I get time, but a formula you > can run on a calculator is much nicer. > Dear Paul, LF group thank you for the above reference . I will also try to program these formulae Easter is coming ... so maybe i will have more time to do it. i already have some fortran routines dealing with special functions ( i use it from time to time) During my search upon the VLF propagation issues i have found another papers of J.R. Wait which could be useful . these are: J.R. Wait, "On the theory of propagation of electromagnetic waves along a curved surface" Can. J. Phys. 1958, Vol.36 ,No 1, pages 9-17 {i have an access to Canadian Journal of Physics at my university library but , unfortunately , not to the 50's ) J.R. Wait: "Two-dimensional treatment of mode theory of the propagation of v.l.f. radio waves" J. Research NBS, 1964, Vol.68D, pages: 81-94 J.R. Wait: "On the theory of mixed-path ground-wave propagation on a spherical earth" J. Research NBS,1961, Vol.65D,No 4, pp.401-410 again, i do not have access to this Journal of Research of National Bureau of Standards as these findings are quite new i had no time to make, say, more "aggressive" search i.e. using my univ. library and ask the library stuff there to continue with the search through the library 'network' . Of course, as I will be successful with these articles ( i.e. having them at hand) will issue you a notice. > Well I think we've squeezed everything possible out of page one! > Yes, I agree! > Here is a nice little essay to read on a tea break, > > http://web.mit.edu/sts/pubs/pdfs/MIT_STS_WorkingPaper_37_Yeang.pdf > > It describes a bygone era in which radio amateurs played a > significant role in scientific research into radio propagation. > I certainly will read it, :) Yours, Piotr, sq7mpj qth: Lodz /jo91rs/