http://rembl.org Seductive serendipity / Verleidende serendipiteit Tue, 06 Jan 2009 06:35:29 +0000 http://backend.userland.com/rss092 en Yesterday I published about the insertion of a leapsceond (in Dutch: schrikkelseconde). About 45 minutes ago I added an update to this post (please scroll down) and discovered that -at that 'time'- the Russian Institute of Metrology for Time and Space (IMVP/VNIIFTRI) lacked to insert the leapsecond in their public NTP ... http://rembl.org/index.php/2009/01/01/does-imvp-vniiftri-read-this-blog/ Short version of this post: look/click at/on the pictures. Long(er) version of this post: read below ; -) Recently a friend of mine offered me rack space in his colocation facility. This facility is connected directly to AMSIX, the nr. 1  internet exchange in the World, located in Amsterdam. He also donated ... http://rembl.org/index.php/2008/12/31/thermostat-for-system-clock/ Today the 34th leapsecond will be inserted in 'our time' by adding a 60th second in the last minute of this year. This was announced by the International Earth Rotation and Reference System Service (IERS) in July this year. Dr. Daniel Gambis, director of the Earth Orientation Centre, explains precisely why insertion ... http://rembl.org/index.php/2008/12/31/today-is-leapsecond-day/ UPDATE 9 nov 2008: Currently ntp2.remco.org runs with the configuration mentioned below. Polling time for the PPS peer is 32 seconds (minpoll 5, maxpoll 5). Stats can be viewed here. UPDATE 8 aug 2008: As I already felt, the idea below is already implemented by Poul-Henning Kamp in his own implementation of ... http://rembl.org/index.php/2008/06/09/dcf77-pps-experiments-with-a-dcf77-radio-module-using-ntpd/ Recently I bought a Motorola Oncore UT+ GPS timing receiver on Ebay. I run Debian Linux and it seems that the refclock_oncore driver is not included in ntpd because the LinuxPPSAPI from Rodolfo Giometti is not an official part of the linux kernel (yet? ; -) I interfaced the module with ... http://rembl.org/index.php/2008/04/19/motorola-oncore-ut-and-linuxpps/ Also this year Joe Walsh invited me, and a few friends, as VIP to his concert of The Eagles. Last time we did not bring a present and we felt a bit guilty. So this time Dick arranged an old Philips tube for Joe and a tile 'Delfts Blauw' to ... http://rembl.org/index.php/2008/04/18/remco-meets-joe-walsh-the-eagles-again/ Although DCF77 seems to be the 'default' time reference for the European continent, I want to have a backup because I run a stratum 0 NTP server. MSF (60 kHz England, UK) is a good candidate. Compared to DCF receivers, MSF receivers are difficult to obtain and expensive on the continent. So, ... http://rembl.org/index.php/2008/03/24/adding-msf-to-your-ntpd-refid-list-or-msf-60-khz-from-dcf-775-khz/ Yesterday I built a 10.000.000 divider with a small cascade of 74LS390's to divide the rubidium 87 (Rb87) locked 10,000.000.00000(0) MHz from my Efratom FRS into 1 Pulse Per Second (PPS). I know that there is a another approach available. However, I managed to program a 16F648A PIC, but the ... http://rembl.org/index.php/2008/02/23/rb87-experiment-with-ntpremcoorg/ In my previous post I reported a succesfull try wih LinuxPPS in conjunction with ntpd's NMEA, ATOM and SHMPPS drivers. However, as far as I could ascertain, the PPS signal from the CIROCOMM G100/300 (I still have not heard anything from them..) can not be locked to the GPS signal ... http://rembl.org/index.php/2008/02/16/rockwell-jupiter-and-linuxpps/ As many of you know, I run an 'open access' stratum 1 NTP server (ntp.remco.org) for almost four years now. In fact, ntp6.remco.org is one of the few open access IPv6 NTP servers worldwide. During this period ntpd was disciplined with a DCF77 radio module, keeping the time within a few ... http://rembl.org/index.php/2008/02/14/linuxpps-cirocomm-nmea-pps-or-dcf/