Return-Path: Received: (qmail 11069 invoked from network); 27 Sep 2002 11:03:09 -0000 Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 27 Sep 2002 11:03:09 -0000 Received: (qmail 7104 invoked from network); 27 Sep 2002 11:03:16 -0000 Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 27 Sep 2002 11:03:16 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 17usqZ-0004Tj-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 27 Sep 2002 11:59:47 +0100 Received: from [212.159.14.227] (helo=warrior.services.quay.plus.net) by post.thorcom.com with smtp (Exim 4.10) id 17usqZ-0004TZ-00 for rsgb_lf_group@blacksheep.org; Fri, 27 Sep 2002 11:59:47 +0100 Received: (qmail 24345 invoked from network); 27 Sep 2002 10:59:16 -0000 Received: from unknown (HELO hugh) (62.60.46.45) by warrior.services.quay.plus.net with SMTP; 27 Sep 2002 10:59:16 -0000 Message-ID: <002301c26614$84f62c60$0504210a@c.scope> From: "g6tmk" To: rsgb_lf_group@blacksheep.org References: <01C26537.C1466D20.g4jnt@thersgb.net> <001601c26609$c8a831c0$0504210a@c.scope> Date: Fri, 27 Sep 2002 11:56:10 +0100 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: Re: RE: Narrow CW filter using 32kHz clock crstals? Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-0.2 required=5.0tests=SUBJ_ENDS_IN_Q_MARK,FROM_NAME_NO_SPACESversion=2.31 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Hello Andy I think I've answered my own question here. I built the filter and it doesn't work with 50 ohm input/output impedance, but it DOES work with 50k ohms. Narrow isn't it ! I can just about hit the right frequency with a signal generator and see some sine wave on the scope. I haven't had a chance to put it on the spectrum analyser yet. 73 Hugh M0WYE ----- Original Message ----- From: "g6tmk" To: Sent: Friday, September 27, 2002 10:39 AM Subject: LF: Re: RE: Narrow CW filter using 32kHz clock crstals? > Hello Andy, > In your recent posting about the 33kHz crystal filter, can you clarify what > the characteristic impedance is ... > It is very unusual to specify an impedance in terms of a frequency, so I > feel there must be some mistake. > Thanks > Hugh M0WYE >