Return-Path: Received: from mtain-mh01.r1000.mx.aol.com (mtain-mh01.r1000.mx.aol.com [172.29.96.213]) by air-mc06.mail.aol.com (v129.10) with ESMTP id MAILINMC064-a9764dcaa148f8; Wed, 11 May 2011 10:46:32 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mh01.r1000.mx.aol.com (Internet Inbound) with ESMTP id AB19438000084; Wed, 11 May 2011 10:46:21 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QKAeJ-0002cs-AL for rs_out_1@blacksheep.org; Wed, 11 May 2011 15:44:27 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QKAeI-0002cj-V0 for rsgb_lf_group@blacksheep.org; Wed, 11 May 2011 15:44:26 +0100 Received: from relay2.uni-heidelberg.de ([129.206.210.211]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QKAeG-0008GE-Ot for rsgb_lf_group@blacksheep.org; Wed, 11 May 2011 15:44:26 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay2.uni-heidelberg.de (8.13.8/8.13.8) with ESMTP id p4BEiNkS014054 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 11 May 2011 16:44:23 +0200 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 p4BEiNGU030421 for ; Wed, 11 May 2011 16:44:23 +0200 Message-ID: <4DCAA066.8090701@iup.uni-heidelberg.de> Date: Wed, 11 May 2011 16:42:46 +0200 From: =?ISO-8859-15?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 X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,RATWARE_GECKO_BUILD=1.426 Subject: LF: Lf Frontend Content-Type: text/plain; charset=ISO-8859-15; 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: 3039ac1d60d54dcaa13d73f9 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) Hello group, Here a picture of my new LF frontend of my active antenna, http://dl.dropbox.com/u/19882028/LF/LF%20frontend.jpg It has a 2 stage bandpass filter in front of the first FET stage (BF862 which is located on the back side). The Q is not very high but DLF and DCF49 are attenuated by about 15 dB. Additionally it provides a kind of HV protection, i hope ;-) But the main purpose is to filter VLF and MF and HF. On the older version i regularly saw MSK traces arround 136.6 kHz. This is 153 kHz (DLF) minus 16.4 kHz (JXN)! :-) After some test time it moves in a water proof PVC tube now and is intended to run 24/7 on the grabber as the omnidirectional antenna. Further improvements will be done in the shack, perhaps. 73, Stefan/DK7FC