Return-Path: Received: from mtain-ma07.r1000.mx.aol.com (mtain-ma07.r1000.mx.aol.com [172.29.96.15]) by air-df03.mail.aol.com (v127_r1.1) with ESMTP id MAILINDF034-5eed4b8c1c54f5; Mon, 01 Mar 2010 14:58:12 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-ma07.r1000.mx.aol.com (Internet Inbound) with ESMTP id 03C15380000B3; Mon, 1 Mar 2010 14:57:58 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NmBjY-0003jX-HY for rs_out_1@blacksheep.org; Mon, 01 Mar 2010 19:56:52 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NmBjY-0003jO-4z for rsgb_lf_group@blacksheep.org; Mon, 01 Mar 2010 19:56:52 +0000 Received: from smtp6.freeserve.com ([193.252.22.190]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NmBjW-00017Q-2l for rsgb_lf_group@blacksheep.org; Mon, 01 Mar 2010 19:56:52 +0000 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3604.me.freeserve.com (SMTP Server) with ESMTP id 57CB7700008E for ; Mon, 1 Mar 2010 20:56:42 +0100 (CET) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3604.me.freeserve.com (SMTP Server) with ESMTP id 4ADC57000095 for ; Mon, 1 Mar 2010 20:56:42 +0100 (CET) Received: from AGB (unknown [91.109.21.19]) by mwinf3604.me.freeserve.com (SMTP Server) with SMTP id C874F700008E for ; Mon, 1 Mar 2010 20:56:39 +0100 (CET) X-ME-UUID: 20100301195639821.C874F700008E@mwinf3604.me.freeserve.com Message-ID: <34EE45A0413B499D9FD2861D88BD4AE1@AGB> From: "Graham" To: References: In-Reply-To: Date: Mon, 1 Mar 2010 19:56:38 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 X-Antivirus: avast! (VPS 100301-0, 01/03/2010), Outbound message X-Antivirus-Status: Clean X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: 9kHz without high voltage Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original 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=0.1 required=5.0 tests=MISSING_OUTLOOK_NAME 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: 3039ac1d600f4b8c1c4614c4 X-AOL-IP: 193.82.116.20 Making a Torodial antenna, as presented at the Egham HFC would be a good start .. the concept of the mirror differed from the published articles ... I made one and oddly it worked quite well at Hf ..how it worked ive no idea .how a 12 inch diameter coil resting on a old no-entry sign (alloy plate) one end fed with coax from the atu the other open achived qso's from 160 to 10 mtrs .. who knows .... .its still hanging in the shed .. but a large one may work at 9 khz without the need for all the coils etc ... Did anyone else attend the lecture ?.. it followed the chap from Birmingham with a selection of loop antennas . .... G ... NB .. Can anyone read this .. as '' design of toroidal reflector ..... Antennas '' is showing in the google search http://www.informaworld.com/smpp/content~content=a770413350&db=all -------------------------------------------------- From: "Alexander S. Yurkov" Sent: Monday, March 01, 2010 1:59 AM To: Subject: LF: 9kHz without high voltage > > > I was wonder if it is posible to use a loop on 9 kHz. Serious problem > to radiate 9 kHz is high voltage we saw. Loop has that advantage that > voltage is not too high. Then i do some estimations. Let's assume vertical > loop 15m x 50 m with 20 mm diameter coper tube as a wire. Then effectivity > of such a loop on 9 kHz is about -65 dB. It is adequate to radiate 1 mW > on 9kHz (I=250A, TX power about 4 kW). We saw such a radiation should > give abt 100 km distance in QRSS. Besides such a loop is wellsuited > for 136 kHz. On 136 kHz it effectivity should be about -25 dB. Not too > bad: 1 W radiation with 400 W TX :-) > > Regards, > Alexander > > > >