Return-Path: Received: from mtain-md09.r1000.mx.aol.com (mtain-md09.r1000.mx.aol.com [172.29.96.93]) by air-di01.mail.aol.com (v129.4) with ESMTP id MAILINDI013-eab84c7d5ed23da; Tue, 31 Aug 2010 15:58:11 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-md09.r1000.mx.aol.com (Internet Inbound) with ESMTP id A4F6738000081; Tue, 31 Aug 2010 15:58:08 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OqWx5-0006wl-JA for rs_out_1@blacksheep.org; Tue, 31 Aug 2010 20:57:03 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OqWx5-0006wb-5F for rsgb_lf_group@blacksheep.org; Tue, 31 Aug 2010 20:57:03 +0100 Received: from mail-gx0-f171.google.com ([209.85.161.171]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OqWvc-0003GA-Qz for rsgb_lf_group@blacksheep.org; Tue, 31 Aug 2010 20:56:58 +0100 Received: by gxk6 with SMTP id 6so3170169gxk.16 for ; Tue, 31 Aug 2010 12:52:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=ODEVNXjDdwvi3I9fqjxS4VVYL2Xnuq5Rr322qLsXZZE=; b=eM6d+/dny4pLY+07oekxHD6ksqgysKi29MZ8FvnpiuYowfMy/mn/774EilmpiBFNCi 5oS2yKc03cLZiySpBU3IUJNqhAN9v+xoj/xuth61heIqmT1pYO7DPga45u5ku4NIdyqJ ly/QQCMKz0L6tBZDMmoioWXSBvJoEjksG4+aM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=byeMVopWtL+bL9YQwvxgYMWLX3ENdyMCt/3oJsPrYrDnalSvXwylM+LD/B/q2a+LUF dNQ6g9JiRgR56A1J3jEg9UzIiQ+iiF3cpsP1uSVuMsnK2EzUW6Xjro/ln596xLawbWht ucQr6C5sZ6774ee9LpNY3QUxaN+IWkowLK9YY= MIME-Version: 1.0 Received: by 10.150.185.4 with SMTP id i4mr2571466ybf.302.1283284354172; Tue, 31 Aug 2010 12:52:34 -0700 (PDT) Received: by 10.231.167.149 with HTTP; Tue, 31 Aug 2010 12:52:34 -0700 (PDT) In-Reply-To: <000a01cb493d$fb8f3410$0401a8c0@xphd97xgq27nyf> References: <000a01cb493d$fb8f3410$0401a8c0@xphd97xgq27nyf> Date: Tue, 31 Aug 2010 20:52:34 +0100 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: VLF THOUGHT Content-Type: multipart/alternative; boundary=000e0cd4d53c13c472048f23ece1 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_20_30,HTML_MESSAGE 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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m203.1 ; domain : googlemail.com DKIM : pass x-aol-sid: 3039ac1d605d4c7d5ecf65b4 X-AOL-IP: 193.82.116.20 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --000e0cd4d53c13c472048f23ece1 Content-Type: text/plain; charset=ISO-8859-1 But think of the animals and birds with their extended hearing range. Andy www.g4jnt.com On 31 August 2010 19:54, mal hamilton wrote: > I see 15 Kilowatt audio amplifiers advertised, therefore there must be a > speaker system, public address horns available for such amplifiers. > If one of these speaker horns was directed line of sight towards the > horizon or a mountain top and a suitable dish positioned at the receive end, > it must be possibel to intercept such a signal at audio frequencies. eg > Transmit a tone which could be keyed at 9 - 20 Kcs and see what distance > could be covered. > Keeping the signal just above the normal human audio range would > avoid interference. > or just TX a signal at say 5 Kcs and see how far it could be heard by ear > with this sort of power, maybe further than the same signal transmitted by > radio means, except one had an exceptionally large antenna > Maybe a NOV is required for this experiment!!!! > de g3kev > > > > > --000e0cd4d53c13c472048f23ece1 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
But think of the animals and birds=A0with their extended hearing rang= e.
On 31 August 2010 19:54, mal hamilton <g3kevmal@talktalk.ne= t> wrote:
I see 15 Kilowatt audio amplifiers ad= vertised, therefore there must be a speaker system, public address horns= available for such amplifiers.
If one of these speaker horns was dir= ected line of sight towards the horizon or a mountain top and a suitable= dish positioned at the receive end, it must be possibel to intercept such= a signal at audio frequencies. eg Transmit a tone which could be keyed=A0= at 9=A0- 20=A0Kcs and see what distance could be covered.
Keeping the signal just above the nor= mal=A0human audio range would avoid=A0interference.
or just TX a signal at say 5 Kcs and= =A0see how far it could be heard=A0by ear with this sort of power, maybe= further than the same signal transmitted by radio means, except one had= an exceptionally large antenna
Maybe a NOV is required for this expe= riment!!!!
de g3kev
=A0
=A0
=A0
=A0=A0

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