Timing Logs and The Sigma Tau maser in Green Bank

Model NAV-2001, serial # 105-17 was installed at Green Bank in 1992.

Timing Plots

These plots give the delay between : The One PPS delays are usually recorded every two minutes. All the data reported here are one hour medians.

Plot for 2007 showing synthesizer adjustments

  • Feb 2, 2007, increase synthesizer by 1000 counts.
  • July 03, 2007, increase synthesizer by 1000 counts.
  • Dec 11, 2007, increase synthesizer by 300 counts.

Plot for 2006 showing synthesizer adjustments

Plot for 2005 showing synthesizer adjustments

(Note the spikes in these plots are due to problems in the recording system, not the maser!)
  • May 4, 2006 : Synthesizer adjust
  • June 8, 2006 : Synthesizer adjust
  • Sept 2, 2006 : Power supply problem
  • Oct 27-28, 2006 : Auto-tune off, back on, adjust 1pps offset.
  • Nov 15, 2006 : Synthesizer adjust

Plot for 2004 (no synthesizer adjustments in 2004)

The jumps are adjustments to the 1 pps zero point of the TRAK master clock. No changes at all were done to the Sigma Tau.

Plot for 2003 (no adjustments in 2003)

Plot for 2002 (rate adjustment April 5)

The jumps are changes to the zero point offset of the TRAK master clock.

Plot for 2001 (no rate adjustments)

The jumps are changes to the zero point offset of the TRAK master clock.

Plot for 2000 (no rate adjustments)

The jumps are changes to the zero point offset of the TRAK master clock.

Plot for 1999 (no rate adjustments)

The jumps are changes to the zero point offset of the TRAK master clock. The spikes are due to problems in the 1pps recording system.

Plot for 1998 (rate adjustment Jan 2)

The ST maser was moved from the Interferometer Control Building basement to the new GBT control building in October.

Plot for 1997 (rate adjustment Jan 2,1998)

Plot for 1996 (rate adjustment Oct 22)

Plot for 1995 (rate adjustment Dec 7)

Timer Data for 1994

Timer Data for March through December, 1993.