USNO VLBA Support Meeting

• Previous Action items: none
• Correlator:
  • Power outage: did last power outage shutdown and restart work?
  • USNO: Nicole doesn't recall powering off infrastructure nodes, works fine with computing nodes.
  • NRAO: We thought there were issues with last power up
  • USNO: Special situations are no longer issue, USNO Action: Will follow up with IT department, regarding what K. Scott sent and which option is best.
  • Upcoming deliverables: Direct delivery of nodes to USNO in ~September
  • Walter will be at USNO starting July 17th for a week, covering SW correlator and anything else that comes up
• MK/PT Status
  • Recent Failures and Observation Modification
  • Masers were replaced at both sites, both working very well
  • NRAO is in process of obtaining a good spare (through lease from 4T)
• Frequency Setup Change Possibility?
  • Walter: Chris discussed possibility and Walter needs to ask questions about # of channels, etc.
  • Action to Walter: To work with Chris and get back up to speed on idea
• USNO retrieval of NRAO correlated data
  • Chris has not figured out how to retrieve data and what USNO has access to.
  • Walter: my.nrao.edu is starting point, email Paul Dyer, Meri Stanely (analysts@nrao.edu)
  • Peggy: Analysts can keep USNO up to date with what has been correlated.
  • Action to Walter: VEX files need Allen IDed as PI
• Daily Observation Report.
  • If more than 15 minutes lost NRAO will do a re-observation.
  • June was a rough month.
  • Chris: Worked on clock offsites, agrees that 15 minutes is a good cutoff. It took effort to get fringes due to clock offsets.
  • Around 3170, there was a big swing in clock offsets and settled back down by 3176.
  • Action NRAO: Starting June 19th, offsets drifted about 300 ns between each experiment until Mark5C recording was brough back on 25th. Then stable (10-20ns drift). Steve to investigate.
• Daily Observations contract renewal
  • Current contract has been funded for 6 months
  • Period of performance is July 18 2013 -January 17, 2014
• Open issues
  • Plan Walter's visit to USNO
  • Next meeting on August 8th. Action to Steve: arrange a hub.
  • Nicole: Is redhat 6.4 compatible with DifX? Walter: concern would be if the kernel version is jumped to a new level that the drivers don't support.