Return-Path: Received: from rly-me03.mx.aol.com (rly-me03.mail.aol.com [172.20.83.36]) by air-me03.mail.aol.com (v125.7) with ESMTP id MAILINME033-9aa4aa16809f7; Fri, 04 Sep 2009 15:18:52 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-me03.mx.aol.com (v125.7) with ESMTP id MAILRELAYINME036-9aa4aa16809f7; Fri, 04 Sep 2009 15:18:35 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MjeHk-0003EQ-Sr for rs_out_1@blacksheep.org; Fri, 04 Sep 2009 20:17:24 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MjeHk-0003EH-EF for rsgb_lf_group@blacksheep.org; Fri, 04 Sep 2009 20:17:24 +0100 Received: from smtp-vbr6.xs4all.nl ([194.109.24.26]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1MjeGo-00082v-VC for rsgb_lf_group@blacksheep.org; Fri, 04 Sep 2009 20:16:27 +0100 Received: from webmail.xs4all.nl (dovemail2.xs4all.nl [194.109.26.4]) by smtp-vbr6.xs4all.nl (8.13.8/8.13.8) with ESMTP id n84JHB2X049712 for ; Fri, 4 Sep 2009 21:17:16 +0200 (CEST) (envelope-from roelof@ndb.demon.nl) Received: from 82.161.81.65 (SquirrelMail authenticated user pa0rdt) by webmail.xs4all.nl with HTTP; Fri, 4 Sep 2009 21:17:16 +0200 Message-ID: <84dd817830a234ab822d5e8d6df8a5e7.squirrel@webmail.xs4all.nl> In-Reply-To: References: <9afca2640908261406r3ced27fr31bbca942848a291@mail.gmail.com> <005701ca2707$438a4570$0301a8c0@mal769a60aa920> <9afca2640908270502q3136dd1cjf52d2666eedeed94@mail.gmail.com> <009c01ca2731$2d5e0e60$0301a8c0@mal769a60aa920> <9afca2640908271133v7eea7f18r7855a822514399a4@mail.gmail.com> <847F3A04E31C413A81AD022BDC11AD46@JimPC> <5CA746FC83614040A4C4D8B6F9F2519E@NIS942960248> <200909041044070836.0E08CA55@smtp2.numeo.fr> Date: Fri, 4 Sep 2009 21:17:16 +0200 From: "Roelof Bakker" To: rsgb_lf_group@blacksheep.org User-Agent: SquirrelMail/1.4.18 MIME-Version: 1.0 X-Virus-Scanned: by XS4ALL Virus Scanner X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Low frequency preselectors? Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit 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-IP: 193.82.116.20 X-Mailer: Unknown (No Version) Hello Jordan, Regarding Q, I have used potcores, but this is not necessary at all. Standard moulded rf chokes, those that look like resistors, give excellent results. I have found that the bandwidth can be so narrow that it was possible to peak the individual sidebands of a 400 Hz modulated non directional beacon at 400 kHz. as said before, decreasing the gain broadens the response to a more practical bandwidth. 73, Roelof Bakker, pa0rdt