Return-Path: Received: from mtain-mg01.r1000.mx.aol.com (mtain-mg01.r1000.mx.aol.com [172.29.96.201]) by air-mc06.mail.aol.com (v127_r1.1) with ESMTP id MAILINMC063-a9754b8401ec28a; Tue, 23 Feb 2010 11:27:24 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mg01.r1000.mx.aol.com (Internet Inbound) with ESMTP id F0F3538000055; Tue, 23 Feb 2010 11:27:14 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NjxaP-0001vB-4I for rs_out_1@blacksheep.org; Tue, 23 Feb 2010 16:26:13 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NjxaO-0001v2-PQ for rsgb_lf_group@blacksheep.org; Tue, 23 Feb 2010 16:26:12 +0000 Received: from mx.omskcity.com ([79.133.160.2]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NjxaL-00053T-N4 for rsgb_lf_group@blacksheep.org; Tue, 23 Feb 2010 16:26:12 +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 o1NGQ4Ff022380 for ; Tue, 23 Feb 2010 22:26:05 +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 XAA00245 for ; Tue, 23 Feb 2010 23:30:55 GMT X-Authentication-Warning: noname.nodomain.nowhere: fitec owned process doing -bs Date: Tue, 23 Feb 2010 23:30:55 +0000 (GMT) From: "Alexander S. Yurkov" To: rsgb_lf_group@blacksheep.org In-Reply-To: <792299.21067.qm@web86506.mail.ird.yahoo.com> 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]); Tue, 23 Feb 2010 22:26:06 +0600 (OMST) X-Spam-Score: 1.5 (+) X-Spam-Report: autolearn=disabled,DATE_IN_FUTURE_06_12=1.498 Subject: Re: LF: VLF_8.79 kHz 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=1.9 required=5.0 tests=DATE_IN_FUTURE_06_12 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: 3039ac1d60c94b8401e278c5 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) > > Nice comment from Alex on near-field....long time since we heard from > you last Alex or maybe I dont read the group enough. Unfortunely i have very few time for ham radio. But i read this group regulary. Usualy i don't write here now. But about VLF i wonder to point out that for near field antenna voltage is more worth then power. Current is too small... Also it is funny that in such a condition signal don't depend on frequency at all! See the formula. But certanly the lower freq the more noise from power lines (50 Hz) in RX point. All of this is obviously in framework of electrostatics. But it is absolutely unusual for radio. Hi. Seems it is a good task for a student to analyse such a problem. Practicaly it is good idea to use high voltage ferrite transformer from old TV set to get high voltage on TX antenna. Make few turns additionaly as primary wireing is not a problem, big secondary wireing is ready in such a transformer. Few km seems to be real. But it is too dificult radiate vlf for large distance in ham conditions. One need real radiation (not 'electrostatic' field) for this. Regards, Alexander/RA9MB