Return-Path: Received: (qmail 42119 invoked from network); 31 Jan 2005 15:11:43 -0000 Received: from unknown (HELO ptb-spamcore01.plus.net) (192.168.71.1) by ptb-mailstore02.plus.net with SMTP; 31 Jan 2005 15:11:43 -0000 Received: from mailnull by ptb-spamcore01.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1CvdDE-000Ik2-BA for dave@picks.force9.co.uk; Mon, 31 Jan 2005 15:11:39 +0000 Received: from [192.168.67.3] (helo=ptb-mxcore03.plus.net) by ptb-spamcore01.plus.net with esmtp (Exim 4.32; FreeBSD) id 1CvdDC-000IjY-Uk for dave@picks.force9.co.uk; Mon, 31 Jan 2005 15:11:35 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore03.plus.net with esmtp (Exim) id 1CvdDQ-0006bb-BB for dave@picks.force9.co.uk; Mon, 31 Jan 2005 15:11:48 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1CvdA0-0002fx-Bh for rs_out_1@blacksheep.org; Mon, 31 Jan 2005 15:08:16 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1CvdA0-0002fo-0K for rsgb_lf_group@blacksheep.org; Mon, 31 Jan 2005 15:08:16 +0000 Received: from smtp800.mail.ukl.yahoo.com ([217.12.12.142]) by relay.thorcom.net with smtp (Exim 4.43) id 1Cvd9w-0007Vo-Ib for rsgb_lf_group@blacksheep.org; Mon, 31 Jan 2005 15:08:15 +0000 Received: from unknown (HELO Main) (Alan.Melia@213.122.174.233 with login) by smtp800.mail.ukl.yahoo.com with SMTP; 31 Jan 2005 15:08:04 -0000 Message-ID: <002f01c507a6$9afc03a0$6507a8c0@Main> From: "Alan Melia" To: rsgb_lf_group@blacksheep.org References: <142.3e3d8156.2f2c1586@aol.com> <5.1.0.14.0.20050131153515.0270c180@u0019445.kuleuven.be> Date: Mon, 31 Jan 2005 15:07:29 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 X-SPF-Result: relay.thorcom.net: 217.12.12.142 is neither permitted nor denied by domain of btinternet.com X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=failed,none Subject: Re: LF: Dummy loads for LF Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Status: No, hits=0.0 required=5.0 tests=none 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-Spam-Filtered: by PlusNet SpamCORE (v3.00) Hi Rik is sounds like our toasers and kettles should all be subject to a "swearing-in" session !! Sorry my company used to sell CB sets at one time. Alan G3NYK ----- Original Message ----- From: "Rik Strobbe" To: Sent: 31 January 2005 14:45 Subject: Re: LF: Dummy loads for LF > Hello Bob, Gary, Markus and others, > > over the past days a lot of household equipment has been suggested as 136 > kHz dummy load. > I wonder what the "cold" resistance of some of these devices are. Most > metals have a positive temperature coefficient of about 0.3 to 0.5 % per > degree centigrade (iron : 0.5%, copper : 0.4%, aluminium : 0.4%). > For oil jacket heaters the temperature at full power may be only 40 degrees > above room temperature (= 20% increased resistance) but for devices like > toasters the change very large. > So a 1000 W toaster (@ 220 V) will be about 50 Ohm when loaded with 1kW but > probably much less if loaded with only 100 Watt. > > 73, Rik ON7YD