Return-Path: Received: (qmail 20048 invoked from network); 31 Jul 2001 22:58:59 -0000 Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur.plus.net with SMTP; 31 Jul 2001 22:58:59 -0000 Received: (qmail 8728 invoked from network); 31 Jul 2001 22:58:40 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 31 Jul 2001 22:58:40 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15RiOa-0000iA-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 31 Jul 2001 23:53:48 +0100 Received: from dc-mx03.cluster0.hsacorp.net ([209.225.8.13] helo=dc-mx03.cluster1.charter.net) by post.thorcom.com with esmtp (Exim 3.16 #2) id 15RiOZ-0000i5-00 for rsgb_lf_group@blacksheep.org; Tue, 31 Jul 2001 23:53:47 +0100 Received: from [24.216.235.182] (HELO johncellar) by dc-mx03.cluster1.charter.net (CommuniGate Pro SMTP 3.4.6) with SMTP id 8820561 for rsgb_lf_group@blacksheep.org; Tue, 31 Jul 2001 18:59:25 -0400 Message-ID: <000901c11a13$75709da0$0300a8c0@charter.net> From: "John Andrews" To: rsgb_lf_group@blacksheep.org References: <002201c119fe$589f3160$e10a97d4@oemcomputer> Subject: LF: Re: SV: LF Receivers Date: Tue, 31 Jul 2001 18:52:21 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Johan, Another interesting clock frequency for 32 bit DDS chips is 3579.13941... kHz, one third the frequency you mentioned. It is easily "pullable" from a common 3579.545 kHz color burst crystal. While it yields tuning steps of the oddball value of 0.8333... mHz, it allows integer math to 10 mHz resolution, which is sufficient for most LF work. I am currently building an LF exciter based on this setup, using an AD9850 DDS chip. John Andrews, W1TAG