Return-Path: Received: (qmail 7343 invoked from network); 17 Jan 2003 12:01:51 -0000 Received: from netmail01.services.quay.plus.net (212.159.14.219) by mailstore with SMTP; 17 Jan 2003 12:01:51 -0000 Received: (qmail 14256 invoked from network); 17 Jan 2003 12:01:41 -0000 Received: from post.thorcom.com (193.82.116.70) by netmail01.services.quay.plus.net with SMTP; 17 Jan 2003 12:01:41 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.12) id 18ZVB2-0008Gf-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 17 Jan 2003 12:00:48 +0000 Received: from [212.159.14.221] (helo=netmail02.services.quay.plus.net) by post.thorcom.com with smtp (Exim 4.12) id 18ZVB2-0008GW-00 for rsgb_lf_group@blacksheep.org; Fri, 17 Jan 2003 12:00:48 +0000 Received: (qmail 25783 invoked from network); 17 Jan 2003 12:00:17 -0000 Received: from ctuash.sonnetinternet.co.uk (HELO hugh) (212.159.90.113) by netmail02.services.quay.plus.net with SMTP; 17 Jan 2003 12:00:17 -0000 Message-ID: <005d01c2be1f$ed4e7200$0504210a@c.scope> From: "g6tmk" To: rsgb_lf_group@blacksheep.org References: <000701c2be0d$16426ee0$6507a8c0@Main> Date: Fri, 17 Jan 2003 11:59:34 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: Re: Notch for DCF39 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-0.3 required=6.0tests=QUOTED_EMAIL_TEXT,REFERENCES,SPAM_PHRASE_00_01, USER_AGENT_OEversion=2.43 X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rsgb_lf_group-outgoing@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false Hello all, Alan wrote: > Hugh has made up the filter and from workbench tests it seems promising. Yes it does what it says on the tin ... I got a notch depth of 47dB. I used a Panasonic ELC08D101E coil available from RS Components part no. 233-5213. I unwound it and found it had 50 turns. Rewinding with 36 turns and tapping at 18 gives the correct 50uH. I think a multiturn pot (or a fixed value resistor in series with a pot) might be best as it is a very sharp adjustment with a single turn type. I used polycarbonate film type capacitors (hen's teeth now Bayer don't make the film any more) Alan and I are presently discussing impedance matching, as it is 100 ohms in, 10k out. 73 Hugh M0WYE http://www.m0wye.thersgb.net/lf.htm > > Details on http://www.alan.melia.btinternet.co.uk/BR-t-Notch.htm >