Return-Path: <owner-rsgb_lf_group@blacksheep.org> Received: from rly-dg09.mx.aol.com (rly-dg09.mail.aol.com [172.19.151.93]) by air-dg05.mail.aol.com (v123.4) with ESMTP id MAILINDG053-5f04a0db5071cc; Fri, 15 May 2009 14:31:51 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dg09.mx.aol.com (v123.4) with ESMTP id MAILRELAYINDG095-5f04a0db5071cc; Fri, 15 May 2009 14:31:37 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1M52BR-0008Oc-K0 for rs_out_1@blacksheep.org; Fri, 15 May 2009 19:31:01 +0100 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1M52BR-0008OT-5g for rsgb_lf_group@blacksheep.org; Fri, 15 May 2009 19:31:01 +0100 Received: from smtp5.freeserve.com ([193.252.22.151] helo=smtp6.freeserve.com) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from <g8fzk@g8fzk.fsnet.co.uk>) id 1M52BP-0004B7-0a for rsgb_lf_group@blacksheep.org; Fri, 15 May 2009 19:31:01 +0100 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3507.me.freeserve.com (SMTP Server) with ESMTP id 809A37000089 for <rsgb_lf_group@blacksheep.org>; Fri, 15 May 2009 20:30:49 +0200 (CEST) Received: from AGB (unknown [91.110.95.175]) by mwinf3507.me.freeserve.com (SMTP Server) with SMTP id EA1847000088 for <rsgb_lf_group@blacksheep.org>; Fri, 15 May 2009 20:30:46 +0200 (CEST) X-ME-UUID: 20090515183046958.EA1847000088@mwinf3507.me.freeserve.com Message-ID: <314E4EC5BF0B4EF0927346C1EABD1DBC@AGB> From: "Graham" <g8fzk@g8fzk.fsnet.co.uk> To: <rsgb_lf_group@blacksheep.org> References: <4A0D91E3.9040602@btconnect.com> In-Reply-To: <4A0D91E3.9040602@btconnect.com> Date: Fri, 15 May 2009 19:30:30 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8064.206 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8064.206 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Aerial current 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-IP: 193.82.116.20 Richard . This bit may of been missed ////// Any ideas? ////// Incidentally, am I best to measure current in the link or in the aerail ////// wire? The ammeter 'has' to be at the point of feed to the Ae and 'not' within the ATU ie in a link .. the circulating currents within the tuner may be extremely large and peak voltages also may be vast , due in part to the Q of the tuner .. my home brew 80 mtr tuner used to un-solder the tap's on the coil and the ww2 cellulite coil separators used to flash over .... As for measuring power with the ammeter into the antenna this is virtually impossible , unless you have a calibrated power meter and are able to , measure the losses in the tuner and the power supplied to the tuner/Ae with a near perfect match , the current value then may be extrapolated and used as a relative measurement .. for that frequency . with that Ae at that time due to the load being 'complex' G .. -------------------------------------------------- From: "Richard Newstead" <g3cwi@btconnect.com> Sent: Friday, May 15, 2009 5:01 PM To: <rsgb_lf_group@blacksheep.org> Subject: LF: Aerial current > > After my success in getting more current into the aerial yesterday I > decided to measure the RF current in the link (link coupled ATU) with a > proper RF ammeter. I was somewhat surprised that the current pinned my 1 > Amp RF meter. How can that be? I can think of some possible reasons: > > 1) The meter is wrong (it must be nearly 70 years old) > 2) The impedance is not 50 Ohms which is odd because I assume the TX is > designed to have a 50 Ohm output and I carefully adjusted the link for > maximum power transfer last night). > 3) The transmitter is giving out far more power than expected (seems > unlikely). > > Any ideas? > > Incidentally, am I best to measure current in the link or in the aerail > wire? > > 73 > > Richard > > PS - beacon on again 501.6kHz. > > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.287 / Virus Database: 270.12.29/2114 - Release Date: 05/14/09 > 06:28:00 >