Message-ID: <5ACEEE96F4F9D41190790002A528B51E693A4C@s0-ott-x11.nrn.nrcan.gc.ca> From: "O'Kane, Daniel" To: "'igsmail@igscb.jpl.nasa.gov'" Subject: [IGSMAIL-3990]: ALGO Hydrogen Maser Clock Date: Wed, 17 Jul 2002 12:50:12 -0400 Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 17 Jul 09:50:19 PDT 2002 Message Number 3990 ****************************************************************************** Author : Dann O'Kane This email is a follow-up to IGS mail #3986 issued on 13Jul2002 DOY 194. At that time, the hydrogen maser clock at ALGO was taken off-line and the GPS receiver was placed on the internal quartz clock. The hydrogen maser is now back in service. The first complete day of GPS data using the hydrogen maser, was Tuesday July 16, 2002, DOY 197. Data for DOY's 194, 195 and 196 are available at CDDIS, but be aware that the data sets will reflect gaps in service and a combination of quartz and hydrogen maser clocks as follows: 194 ( Maser from to) 00:00:00 to 10:45:00 UTC 194 ( NO clock - site down) 10:45:00 to 13:45:00 UTC 194 ( Quartz from to) 13:45:00 to 24:00:00 UTC 195 ( Quartz from to) 00:00:00 to 24:00:00 UTC 196 ( Quartz from to) 00:00:00 to 04:41:00 UTC 196 (NO clock- site down) 04:41:00 to 13:45:00 UTC 196 (Maser from to) 13:45:00 to 17:23:00 UTC 196 (NO clock - site down) 17:23:00 to 18:15:30 UTC 196 ( Maser from to) 18:15:30 to 24:00:00 UTC