Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dl03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 3A855380000F8; Sat, 9 Mar 2013 09:48:43 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1UEKYb-0000lA-MJ for rs_out_1@blacksheep.org; Sat, 09 Mar 2013 14:15:29 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1UEKYb-0000l1-9K for rsgb_lf_group@blacksheep.org; Sat, 09 Mar 2013 14:15:29 +0000 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1UEKYZ-00056G-40 for rsgb_lf_group@blacksheep.org; Sat, 09 Mar 2013 14:15:28 +0000 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id r29EF6LO018729 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sat, 9 Mar 2013 15:15:06 +0100 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id r29EF6gP023669 for ; Sat, 9 Mar 2013 15:15:06 +0100 Message-ID: <513B43E5.80600@iup.uni-heidelberg.de> Date: Sat, 09 Mar 2013 15:15:01 +0100 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: In-Reply-To: X-Spam-Score: -1.3 (-) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Dimitris, Here i'm also using a AMradiuo IF filter, a mechanical one. There are available in a German surplus store, http://www.oppermann-electronic.de/html/body_hf-spezialbauteile.html FZ-02. Now they cost 6 Euro, i remember they started with 5 EUR ;-) Anyway cheap i find because they work really excellent and the effort isn't high to get good results. I've got this filter curve in a recent measurement: https://dl.dropbox.com/u/19882028/MF/473%20kHz%20ZF%20Filter%2040%20dB.png and https://dl.dropbox.com/u/19882028/MF/473%20kHz%20ZF%20Filter%201%20dB.png Datasheet: https://dl.dropbox.com/u/19882028/MF/FZ_01_FZ_02.pdf [...] Content analysis details: (-1.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [129.206.100.212 listed in list.dnswl.org] -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Scan-Signature: 0a4643e586472c13187d293ec5d096c2 Subject: Re: LF: simple 475 kHz BPF Content-Type: text/plain; charset=ISO-8859-1; format=flowed 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-global-disposition: G x-aol-sid: 3039ac1d4ad1513b4bc85590 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : temperror Hi Dimitris, Here i'm also using a AMradiuo IF filter, a mechanical one. There are available in a German surplus store, http://www.oppermann-electronic.de/html/body_hf-spezialbauteile.html FZ-02. Now they cost 6 Euro, i remember they started with 5 EUR ;-) Anyway cheap i find because they work really excellent and the effort isn't high to get good results. I've got this filter curve in a recent measurement: https://dl.dropbox.com/u/19882028/MF/473%20kHz%20ZF%20Filter%2040%20dB.png and https://dl.dropbox.com/u/19882028/MF/473%20kHz%20ZF%20Filter%201%20dB.png Datasheet: https://dl.dropbox.com/u/19882028/MF/FZ_01_FZ_02.pdf 73, Stefan/DK7FC Am 09.03.2013 04:52, schrieb Dimitrios Tsifakis: > Hello group, > > I apologise if I am stating the obvious, but perhaps this will be of > interest to someone. Old AM radio IF transformers connected back to > back via a tiny capacitor make a simple but effective 475 kHz BPF: > > http://people.physics.anu.edu.au/~dxt103/472/rx_bpf/ > > 73, Dimitris VK1SV >