X-GM-THRID: 1200537839364361837 X-Gmail-Labels: rsgb lf X-Gmail-Received: a8bbc42b6ddb85cc2c0a73824afa72a9c9e7bad5 Delivered-To: daveyxm@gmail.com Received: by 10.54.70.6 with SMTP id s6cs31900wra; Thu, 13 Apr 2006 02:55:03 -0700 (PDT) Received: by 10.65.224.3 with SMTP id b3mr181732qbr; Thu, 13 Apr 2006 02:55:03 -0700 (PDT) Return-Path: Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mx.gmail.com with ESMTP id e15si401494qbe.2006.04.13.02.55.01; Thu, 13 Apr 2006 02:55:03 -0700 (PDT) Received-SPF: neutral (gmail.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1FTyVa-0003u2-Cv for rs_out_1@blacksheep.org; Thu, 13 Apr 2006 10:53:02 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1FTyVa-0003tt-1B for rsgb_lf_group@blacksheep.org; Thu, 13 Apr 2006 10:53:02 +0100 Received: from mail.gmx.net ([213.165.64.20]) by relay1.thorcom.net with smtp (Exim 4.51) id 1FU0Fi-0002WF-LG for rsgb_lf_group@blacksheep.org; Thu, 13 Apr 2006 12:45:02 +0100 Received: (qmail invoked by alias); 13 Apr 2006 09:52:40 -0000 Received: from p54907873.dip.t-dialin.net (EHLO router) [84.144.120.115] by mail.gmx.net (mp043) with SMTP; 13 Apr 2006 11:52:40 +0200 X-Authenticated: #9373712 Message-ID: <002a01c65ee0$c449e460$0600a8c0@router> From: "Uwe Wensauer" To: References: Date: Thu, 13 Apr 2006 11:58:07 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1409 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Y-GMX-Trusted: 0 X-Spam-Score: -1.2 (-) X-Spam-Report: autolearn=disabled,AWL=-1.155 Subject: LF: Re: preamp 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 Status: O X-Status: X-Keywords: X-UID: 6515 Hi Victor, this Pre- Amp looks nice, but ... such a design is useless until in order to reproduce it, all parts must be to get. So, what are the datas for the transformer s "wit" "Geel" and "Zwart" and from where may I get it ? uwe, dk1kq ----- Original Message ----- From: "Victor van kooten" To: "blacksheep" Sent: Thursday, April 13, 2006 11:22 AM Subject: LF: preamp > Hello all, > > since some months I am listening to the 136KHz band with a Icom IC761,this > is a good HF tranceiver but on longwave it has some intermodulation problems > with local broadcasting stations on 675KHz and higher.To solve this I build > a narrowband preamp,also suitable for a whip antenna.Enclosed the circuit,a > picture of the filter shape follows. > B-3 dB : 3 KHz > B-60dB : 28 KHz > No more IM problems on any receiver I use.To compensate for the gain on the > 50 Ohm input I use the 20 dB attentuator on the IC761. > > Greetings, > > Victor > PA3FNY >