Return-Path: Received: from mtain-dc06.r1000.mx.aol.com (mtain-dc06.r1000.mx.aol.com [172.29.64.134]) by air-db06.mail.aol.com (v126.13) with ESMTP id MAILINDB061-85f24b58aaf5339; Thu, 21 Jan 2010 14:28:53 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dc06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 677FC38000095; Thu, 21 Jan 2010 14:28:51 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NY2h8-0006nb-Na for rs_out_1@blacksheep.org; Thu, 21 Jan 2010 19:27:54 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NY2h8-0006nS-7j for rsgb_lf_group@blacksheep.org; Thu, 21 Jan 2010 19:27:54 +0000 Received: from mail-fx0-f217.google.com ([209.85.220.217]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NY2h5-0008EU-1a for rsgb_lf_group@blacksheep.org; Thu, 21 Jan 2010 19:27:54 +0000 Received: by fxm9 with SMTP id 9so379096fxm.30 for ; Thu, 21 Jan 2010 11:27:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=KMle7UTUnKcAT3aF8zL6y28eKv/Wz1g178gpCt47WJc=; b=jDisII1C3wAti1Mn2/xxzL9rAxlXkb5sewmYCfTCN84t53xqN0vfPdJxWpXNVGyXhm bajt9T7hALVkfUafb97i50meHeU/0rrhHuYNjqJzpnrsQWq/pGiewP7mwjKfUL/Z99bE 45cHpaKtDWPfcBWpOhRBicIPcCc8MAJebW4mE= 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=L09IqAu5r+PA+mhifXRy0k3jml/cBu5mT+B6zPk9xnAoTvPkdLoTHwNaGjSVMq01CF t36UdnjEQi9M4bHY4CuKIY2n/gST3Nc302l4wsUkmNnwd8syiAfnkD1+s0s9yxKkrvnZ YGSNcb2+LFewhx7hDoWlny5zJS12mZzizeyKY= MIME-Version: 1.0 Received: by 10.239.186.133 with SMTP id g5mr211465hbh.182.1264102064036; Thu, 21 Jan 2010 11:27:44 -0800 (PST) In-Reply-To: <007501ca9acc$e78e29a0$0301a8c0@your91hoehfy9g> References: <9afca2641001210904h7d2b276dv503b55075ce9313@mail.gmail.com> <007501ca9acc$e78e29a0$0301a8c0@your91hoehfy9g> Date: Thu, 21 Jan 2010 19:27:43 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org X-Karma: unknown: DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: Re: M0BMU - any chance of some new ERP estimates please? Content-Type: multipart/alternative; boundary=001485f453347c9b9a047db1b2bd X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.8 required=5.0 tests=HTML_30_40,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-sid: 3039ac1d40864b58aaf35ee5 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --001485f453347c9b9a047db1b2bd Content-Type: text/plain; charset=ISO-8859-1 So go on: argue against the Rrad (an exact figure derived from basic electromag theory) and Rloss (easily measurable, called Ohms law) way of getting antenna efficiency. Or ERP = I^2 . Rrad where I is measurable. Only uncertainty in any of these techniques is the effective height of the antenna used to get Rrad, but absolute worst case, can only ever lead to 6dB error. The difference between no top hat and an infinite top hat Andy www.g4jnt.com 2010/1/21 mal hamilton > Rik's figures are always exaggarated could be plus/minus 100 dB either > way. Recent dipole gain figures from Rik indicated that I am running 400 mw > erp. > whereas some months ago his estimate on received signals from me was 20 > plus watts and here there has been no changes here same old TX/ANTENNA. > Figures from others over the years have been totally wrong, ALL > GUESSWORK, think of a figure juggle it about and publish. > In the amateur context depending on site, theory and practical are often a > long way apart. > When I have queried these figures there is NO RESPONSE > G3KEV > > > > > ----- Original Message ----- > *From:* Roger Lapthorn > *To:* rsgb_lf_group@blacksheep.org ; James Moritz > *Sent:* Thursday, January 21, 2010 5:04 PM > *Subject:* LF: M0BMU - any chance of some new ERP estimates please? > > Dear Jim, > > Following the discussion on the LF reflector in the last 24 hours, I wonder > if we could use your experience and expertise to estimate the most recent > ERP levels for G4JNT, G3ZJO and G3XBM please. Based on Rik's figures we've > some doubt whether Andy G4JNT is being a little optimistic or whether Eddie > and I are being pessimistic or whether the truth is somewhere in between. > > Would much appreciate this. Thanks > > 73s > Roger G3XBM > > -- > > http://g3xbm-qrp.blogspot.com/ > http://www.g3xbm.co.uk > http://www.youtube.com/user/G3XBM > G3XBM GQRP 1678 ISWL G11088 > > --001485f453347c9b9a047db1b2bd Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
So go on:=A0 argue against the Rrad (an exact figure derived from bas= ic electromag theory) and Rloss (easily measurable, called Ohms law) way= of getting antenna efficiency.=A0=A0
=A0
Or=A0 ERP =3D=A0 =A0I^2 . Rrad=A0=A0 where I is measurable.
=A0
Only uncertainty in any of these techniques is the effective height= of the antenna used to get Rrad, but absolute worst case, can only ever= lead to 6dB error.=A0 The difference between no top hat and an infinite= top hat

Andy
www.g4jnt.com



2010/1/21 mal hamilton <g3kevmal@talktalk.net>
Rik's figures are always exaggara= ted could be plus/minus 100 dB either way. Recent dipole gain figures=A0fr= om=A0Rik=A0indicated that I am running 400 mw erp.
=A0=A0=A0 whereas some months ago his= estimate on received signals from me=A0was 20 plus watts and here there= =A0has been no changes here same old TX/ANTENNA.
=A0Figures from others over the years have been totally wrong, ALL GUESS= WORK, think of a figure=A0juggle it about and=A0publish.
In the amateur context depending on= site, =A0theory and practical=A0are often a long way apart.
When=A0I have queried these figures= there is NO RESPONSE
G3KEV
=A0=A0=A0
=A0
=A0
----- Original Message -----
Sent: Thursday, January 21, 2010 5:= 04 PM
Subject: LF: M0BMU - any chance of= some new ERP estimates please?

Dear Jim,

Following the discussion on the LF reflect= or in the last 24 hours, I wonder if we could use your experience and expe= rtise to estimate the most recent ERP levels for G4JNT, G3ZJO and G3XBM pl= ease. Based on Rik's figures we've some doubt whether Andy G4JNT= is being a little optimistic or whether Eddie and I are being pessimistic= or whether the truth is somewhere in between.

Would much appreciate this. Thanks

73s
Roger G3XBM

--

http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www= .youtube.com/user/G3XBM
G3XBM =A0 =A0GQRP 1678 =A0 =A0 =A0ISWL G110= 88

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