Return-Path: Received: (qmail 4878 invoked from network); 30 Nov 2002 19:13:22 -0000 Received: from murphys.services.quay.plus.net (212.159.14.225) by mailstore with SMTP; 30 Nov 2002 19:13:22 -0000 Received: (qmail 7545 invoked from network); 30 Nov 2002 19:13:41 -0000 Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 30 Nov 2002 19:13:41 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18ID3A-0003K1-00 for rsgb_lf_group-outgoing@blacksheep.org; Sat, 30 Nov 2002 19:13:12 +0000 Received: from [194.73.73.176] (helo=protactinium) by post.thorcom.com with esmtp (Exim 4.10) id 18ID39-0003Js-00 for rsgb_lf_group@blacksheep.org; Sat, 30 Nov 2002 19:13:11 +0000 Received: from host213-1-185-158.in-addr.btopenworld.com ([213.1.185.158] helo=main) by protactinium with smtp (Exim 3.22 #16) id 18ID38-00065z-00 for rsgb_lf_group@blacksheep.org; Sat, 30 Nov 2002 19:13:11 +0000 Message-ID: <002001c298a4$647bf920$9eb901d5@main> From: "Alan Melia" To: "LF-Group" Date: Sat, 30 Nov 2002 18:49:26 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: Frequency Standards..... Content-Type: text/plain; charset=Windows-1252; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=0.7 required=5.0tests=SPAM_PHRASE_01_02,USER_AGENT_OEversion=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Hi all, ever wondered what a Cesium Clock was...... or how a Rubidium standard worked.....why do crystals "age"..... ?? It's all explained now....I found an old copy of an NBS Tutorial (dated 1977) which covers all these and many more interesting facets of Time and Frequency standards. I have scanned it and made it available as a .PDF file in two parts, which can be downloaded from the index page of my web site. It even covers the 2003 "must have" the Hydrogen Maser....anyone for parts in 10^13 ?? Cheers de Alan G3NYK alan.melia@btinternet.com http://www.alan.melia.btinternet.co.uk