X-GM-THRID: 1211252742720040667 X-Gmail-Labels: rsgb lf X-Gmail-Received: 4be7198e43cf5aa3026f21854af63028c9f9365a Delivered-To: daveyxm@gmail.com Received: by 10.64.249.16 with SMTP id w16cs54194qbh; Wed, 9 Aug 2006 09:23:51 -0700 (PDT) Received: by 10.49.75.2 with SMTP id c2mr1716673nfl; Wed, 09 Aug 2006 09:23:51 -0700 (PDT) Return-Path: Received: from post.thorcom.com ([193.82.116.20]) by mx.gmail.com with ESMTP id l38si290929nfc.2006.08.09.09.23.37; Wed, 09 Aug 2006 09:23:51 -0700 (PDT) Received-SPF: error (gmail.com: error in processing during lookup of owner-rsgb_lf_group@blacksheep.org: DNS timeout) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1GAqmj-0006cS-Pd for rs_out_1@blacksheep.org; Wed, 09 Aug 2006 17:19:57 +0100 Received: from [193.82.59.130] (helo=relay2.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1GAqmj-0006cJ-7V for rsgb_lf_group@blacksheep.org; Wed, 09 Aug 2006 17:19:57 +0100 Received: from post-24.mail.nl.demon.net ([194.159.73.194]) by relay2.thorcom.net with esmtp (Exim 4.51) id 1GAqmf-0007oY-Eh for rsgb_lf_group@blacksheep.org; Wed, 09 Aug 2006 17:19:57 +0100 Received: from ndb.demon.nl ([82.161.81.65]:29167 helo=pcroelof) by post-24.mail.nl.demon.net with smtp (Exim 4.51) id 1GAqme-000PVS-7f for rsgb_lf_group@blacksheep.org; Wed, 09 Aug 2006 16:19:52 +0000 Message-ID: <000501c6bbcf$9e65e4a0$2101a8c0@pcroelof> From: "Roelof Bakker" To: References: Date: Wed, 9 Aug 2006 18:19:41 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Spam-Score: -0.4 (/) X-Spam-Report: autolearn=disabled,AWL=-0.393 Subject: LF: Re: 134.1Khz Content-Type: text/plain; format=flowed; charset="Windows-1252"; reply-type=original 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 Status: O X-Status: X-Keywords: X-UID: 4722 Hello Laurence, Glad to hear the design is working fine. Though there are now more than 120 around, as far as I know, it is the first one in Asia! >> The only difference to the original design is a slightly longer (cap) >> aerial, added another few cms there, and the inter-stage coupling >> increased to 680pF from 560pF, only because thats what they have and not >> to improve the LF side << This value is not very critical, but it should be in the order of > 100 nF (0.1 �F) to achieve good VLF performance. 680 pF is a little on the low side, I guess. Adding a few cm length to the PCB antenna does not make much of a difference. Doubling the size gives only 3 dB(m) more signal. It has been designed to prevent overload of the receiver, but again nothing critical. I am following your endeavers with great interest. Best regards, Roelof Bakker, pa0rdt