Return-Path: Received: from mtain-mc01.r1000.mx.aol.com (mtain-mc01.r1000.mx.aol.com [172.29.96.73]) by air-mb08.mail.aol.com (v127_r1.1) with ESMTP id MAILINMB084-a8064ba4eade2e5; Sat, 20 Mar 2010 11:33:50 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mc01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 5A8EC380000D2; Sat, 20 Mar 2010 11:33:49 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Nt0f0-00028B-F6 for rs_out_1@blacksheep.org; Sat, 20 Mar 2010 15:32:22 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Nt0f0-000282-0f for rsgb_lf_group@blacksheep.org; Sat, 20 Mar 2010 15:32:22 +0000 Received: from mx.omskcity.com ([79.133.160.2]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Nt0ex-0004Ib-1M for rsgb_lf_group@blacksheep.org; Sat, 20 Mar 2010 15:32:21 +0000 Received: from noname.nodomain.nowhere (host209.161-133-79.sotline.ru [79.133.161.209]) by mx.omskcity.com (8.13.6/8.13.6) with ESMTP id o2KFWDIh070618 for ; Sat, 20 Mar 2010 21:32:14 +0600 (OMST) (envelope-from fitec@omskcity.com) Received: from localhost (fitec@localhost) by noname.nodomain.nowhere (8.8.5/8.8.5) with SMTP id PAA00371 for ; Sat, 20 Mar 2010 15:26:49 GMT X-Authentication-Warning: noname.nodomain.nowhere: fitec owned process doing -bs Date: Sat, 20 Mar 2010 15:26:49 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-Reply-To: <4BA4A867.1060907@abelian.org> Message-ID: MIME-Version: 1.0 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.1.8 (mx.omskcity.com [79.133.160.2]); Sat, 20 Mar 2010 21:32:16 +0600 (OMST) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Cooperative ionosphere effects Content-Type: TEXT/PLAIN; charset=US-ASCII 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: 3039ac1d60494ba4eadd5d15 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) On Sat, 20 Mar 2010, Paul Nicholson wrote: > the calculations, but one might imagine a system comprising a > beacon tx with slow triangular FM and a rx or coherent network > of rxs scanning for a weak delayed echo - the same triangular > modulation but delayed perhaps up to half a second or so. > Software would have to de-chirp the triangle for all range > of delays, with continuous moving average over 10 or 20 mins > to dig the echo out of the noise. If that could be made to > work, researchers would be falling over themselves to get at > your data! By the way one can imagine some 'reverse whistler' if TX radiate apropriate FM signal which is 'de-chirped' by dispersion in ionosphere. Can you roughly estimate radiated power needed to observe such 'naturaly compressed' signal? I expect it is not 'amateur' power. But it is interesting is this power reachable for professional station or not. Regards, Alexander