Return-Path: Received: from mtain-mb04.r1000.mx.aol.com (mtain-mb04.r1000.mx.aol.com [172.29.96.24]) by air-da09.mail.aol.com (v129.4) with ESMTP id MAILINDA091-85eb4d093a8134e; Wed, 15 Dec 2010 17:00:33 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mb04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1CB02380000D8; Wed, 15 Dec 2010 17:00:24 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PSzMz-000277-8M for rs_out_1@blacksheep.org; Wed, 15 Dec 2010 21:58:45 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PSzMy-00026y-Rv for rsgb_lf_group@blacksheep.org; Wed, 15 Dec 2010 21:58:44 +0000 Received: from nm3.bullet.mail.ukl.yahoo.com ([217.146.182.224]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1PSzMx-0008Ru-8B for rsgb_lf_group@blacksheep.org; Wed, 15 Dec 2010 21:58:44 +0000 Received: from [217.146.183.208] by nm3.bullet.mail.ukl.yahoo.com with NNFMP; 15 Dec 2010 21:58:37 -0000 Received: from [217.146.183.72] by tm1.bullet.mail.ukl.yahoo.com with NNFMP; 15 Dec 2010 21:58:37 -0000 Received: from [127.0.0.1] by omp1033.mail.ukl.yahoo.com with NNFMP; 15 Dec 2010 21:58:37 -0000 X-Yahoo-Newman-Id: 561531.15289.bm@omp1033.mail.ukl.yahoo.com Received: (qmail 47445 invoked from network); 15 Dec 2010 21:58:37 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btinternet.com; h=DKIM-Signature:Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE:X-Antivirus:X-Antivirus-Status; b=p8X98PrTACnMnnFQDxxgEyQ4BI0ZbNbh1TfIco6IBOrTz3Ruqqt7bvcGru+D/SJVCF5NL9o4oFSppndKWmUR2hu4AqxY8129L7kWTTn0YLvI8P9nzNQY5zulcaoBi4i2IVIc/q/buNY1HZJZUCpBTxQhyjO5xrczBWtlHmqg7Vw= ; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=s1024; t=1292450317; bh=XbhhraDt3Xq3AMA9Z0l/w5ZJVrcYdULC+OxZ+zTqpys=; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE:X-Antivirus:X-Antivirus-Status; b=qQYkqxOlKREB17sbpKB+0Ndumwbc07BIN1CS5LuZWLk7D/rCphZgqm0BPFOpWI8jQCVWopfbfglmWJ5zhmCzzQX5axOb4cDlXfEvo5j55ceLWDYJqQAO9YLhtPWrgfrJC7KpqYGIqQp8DbNo9DloRj4Fhso2d7KHr8ngcJFDTxE= Received: from lark (alan.melia@86.157.31.254 with login) by smtp817.mail.ukl.yahoo.com with SMTP; 15 Dec 2010 21:58:34 +0000 GMT X-Yahoo-SMTP: fpz.2VeswBBs59bVshRPmMN51lcO2lgFRIvE4XTqE8dRwOxd70E- X-YMail-OSG: jJLHIKwVM1mdEEXTEzHbhuiGV0z6BAs8IpaebtJJ62ZyZde iF2e6fbWqLF6I9m53qai_Kf1mFXBaGG_UObAeBYSzz1STJaSFGyfApvH3Iu7 vkgKtg2Ez8sWxzg8AkfWOqtLRHLl_wxunlLma7ciH5z_Ck2BJs2G.WxXabre AhfUt.i5fBQigZdJGQ1Wl.uZma83Qi8lRQbSNiXQS1CBRcl_yy1Hqucquedj TCfRZkcZH1lEMiuzsAMkbxoApEL9lywatd8P8un5pkvNYj8HoHcFlzfOr8VD Y1R5fVe3H1Dp0s_fh0.WSi5b8.d0VeEo1Lhx3qlaASyOJIzC.70RcyQ-- X-Yahoo-Newman-Property: ymail-3 Message-ID: <003d01cb9ca3$3eb6a2b0$4001a8c0@lark> From: "Alan Melia" To: "RSGB LF Gp" References: <5BB571709EEB4C2084239E924B0EACEE@lindavideo> Date: Wed, 15 Dec 2010 21:58:32 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.2001 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.2001 X-Antivirus: avast! (VPS 101215-1, 15/12/2010), Outbound message X-Antivirus-Status: Clean DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,UNPARSEABLE_RELAY=0.001 Subject: LF: Re: Sound Card Impedance Content-Type: text/plain; charset="iso-8859-1" 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=0.0 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-aol-sid: 3039ac1d60184d093a7705a8 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hi Ken stick a steady signal into the card on one channel, (use one of the waterfalls) but put a small, say 20k, pot connected as a variable resistance in series with the source. Wind up the pot' til the signal drops 6dB. Remove the pot and carefully measure the resistance that reduced the level by 6dB and that is the input impedance of the card. Best wishes Alan G3NYK ----- Original Message ----- From: "Ken" To: Sent: Wednesday, December 15, 2010 8:09 PM Subject: LF: Sound Card Impedance Hello all. Does anyone know the approximate impedance of the mic input jack on a pc sound card. 73. Ken M0KHW