Return-Path: Received: (qmail 1941 invoked from network); 1 Aug 2001 11:03:37 -0000 Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur.plus.net with SMTP; 1 Aug 2001 11:03:37 -0000 Received: (qmail 4473 invoked from network); 1 Aug 2001 11:03:04 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 1 Aug 2001 11:03:04 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15Rth5-0007Sn-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 01 Aug 2001 11:57:39 +0100 Received: from relay.dera.gov.uk ([192.5.29.49]) by post.thorcom.com with smtp (Exim 3.16 #2) id 15Rth3-0007RO-00 for rsgb_lf_group@blacksheep.org; Wed, 01 Aug 2001 11:57:37 +0100 Content-Transfer-Encoding: 8bit Received: (qmail 18059 invoked from network); 1 Aug 2001 11:54:52 +0100 Received: from trtnmail.dera.gov.uk (146.80.9.56) by relay.dera.gov.uk with SMTP; 1 Aug 2001 11:54:52 +0100 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 24650 invoked from network); 1 Aug 2001 11:59:02 +0100 Received: (ofmipd 192.5.29.90); 1 Aug 2001 10:58:40 -0000 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id MAA15268; Wed, 1 Aug 2001 12:02:52 +0100 (BST) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: (qmail 21424 invoked from network); 1 Aug 2001 11:48:18 -0000 Received: from gauntlet.mail.dera.gov.uk (172.16.9.10) by baton.dera.gov.uk with SMTP; 1 Aug 2001 11:48:18 -0000 Received: by gauntlet.mail.dera.gov.uk; id LAA10508; Wed, 1 Aug 2001 11:35:54 GMT Received: from unknown(10.71.64.31) by gauntlet.mail.dera.gov.uk via smap (3.2) id xma010502; Wed, 1 Aug 01 11:35:32 GMT Received: from mailex.dera.gov.uk (unverified) by mailguard.dera.gov.uk (Content Technologies SMTPRS 4.1.5) with SMTP id for ; Wed, 1 Aug 2001 11:56:30 +0100 Received: (qmail 3283 invoked from network); 1 Aug 2001 10:45:03 +0100 Date: 1 Aug 2001 11:55:06 +0100 Message-ID: <7D653C9C42F5D411A27C00508BF8803D55C575@pdw-mail-r1.dstl.gov.uk> From: "Andrew Talbot" To: rsgb_lf_group@blacksheep.org X-5Received: from softdnserror (HELO cchecker.dstl.gov.uk) (192.168.248.52) by mailex.dstl.gov.uk with SMTP; 1 Aug 2001 09:45:03 -0000 X-4Received: from FRN-MAIL-R3.dstl.gov.uk (unverified) by cchecker.dstl.gov.uk (Content Technologies SMTPRS 4.1.2) with ESMTP id for ; Wed, 1 Aug 2001 10:44:53 +0100 X-3Received: by FRN-MAIL-R3 with Internet Mail Service (5.5.2650.21)id ; Wed, 1 Aug 2001 11:55:05 +0100 Subject: LF: RE: SV: LF Receivers MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: What an elegant solution ! For a signal generator as a piece of test equipment its ideal ! Although for my purposes in a receiver, exact frequency increments are not necessary provided the exact value is known. Furthermore the more 'rubbery' or pullable the crystal is, you can make the PLL wider bandwidth, so reducing phase noise. Furthermore, instead of using 1MHz derived via a PLL etc from GPS, you could programme the fixed DDS with a code of 40 and generate a 1Hz signal which you could then lock to 1s GPS pulses directly. Andy, > Not if it is phase locked to the 5/10MHz standard. > > My idea was to use a second DDS chip as divider (with fixed "nice number" > phase increment) to get a "nice number" PLL reference frequency. The VCXO > is then the only odd-ball frequency in the system. > -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.