Return-Path: Received: from mtain-mj02.r1000.mx.aol.com (mtain-mj02.r1000.mail.aol.com [172.21.164.86]) by air-mc03.mail.aol.com (v129.4) with ESMTP id MAILINMC034-a8de4d851cbd380; Sat, 19 Mar 2011 17:14:37 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mj02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 290923800008F; Sat, 19 Mar 2011 17:14:35 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Q13SW-0006xA-Ij for rs_out_1@blacksheep.org; Sat, 19 Mar 2011 21:13:16 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Q13SW-0006x1-6D for rsgb_lf_group@blacksheep.org; Sat, 19 Mar 2011 21:13:16 +0000 Received: from mhost02c.leeds.ac.uk ([129.11.76.154]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Q13SU-0003qx-E6 for rsgb_lf_group@blacksheep.org; Sat, 19 Mar 2011 21:13:16 +0000 Received: from APOLLO1.ds.leeds.ac.uk (apollo1.leeds.ac.uk [129.11.5.4]) by mhost02c.leeds.ac.uk (8.14.4/8.14.4) with ESMTP id p2JLD8jk010366 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT) for ; Sat, 19 Mar 2011 21:13:08 GMT Received: from HERMES8.ds.leeds.ac.uk ([fe80::39ce:23e:d0b5:7e24]) by APOLLO1.ds.leeds.ac.uk ([129.11.5.4]) with mapi; Sat, 19 Mar 2011 21:13:08 +0000 From: Chris Trayner To: "rsgb_lf_group@blacksheep.org" Date: Sat, 19 Mar 2011 21:13:07 +0000 Thread-Topic: LF: Re: Frequency Stability Thread-Index: AcvmenHUCWO52QpRQLGtTMv4BJne2A== Message-ID: <8CAE351D-C09D-46CE-BE9E-3BEA141DCEFC@leeds.ac.uk> References: <4D83CAEE.2060305@freenet.de> <3D88D5AFC0094751A8CA041C9700D50E@JimPC> In-Reply-To: <3D88D5AFC0094751A8CA041C9700D50E@JimPC> Accept-Language: en-US, en-GB Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US, en-GB MIME-Version: 1.0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: Frequency Stability Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable 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=TO_ADDRESS_EQ_REAL 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 x-aol-global-disposition: G x-aol-sid: 3039400c89a44d851cbb4953 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) > It seems the=20 > 198kHz carrier has some kind of cyclical drift in phase which occurs ove= r a=20 > period of a minute or two Actually, for your communication purposes, do you need a stable frequency? If Tx and Rx both lock to BBC Radio 4 or MSF or whatever, it doesn't matte= r if it drifts. Both amateur Tx and Rx drift together, so you can still ha= ve a very narrow-band filter. You could call it LOWFUSS - LOW Frequency Unintended Spread Spectrum ;-) 73, Chris G4OKW ----------------------- Dr Chris Trayner School of Electronic & Electrical Engineering, The University of Leeds, Leeds LS2 9JT, United Kingdom Tel: +44 113 34 32053 Fax: +44 113 34 32032