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AuScope VLBI Operations meeting : 29 Aug 2013

Present: Jim Lovell, Jamie McCallum, Ellen Manning, Imogen Jones, Mark Howe, Dave Horsley, Jacqui Howe, Warren Hankey

  1. Review of recent experiments. The following items were raised following an examination of recent operator logs, correlator reports and analyst reports:
    1. Experiments discussed are listed below and a table summarising them is on the wiki on the Operations Summary page. Those marked with a * should be re-visited in future meetings when a correlator/analyst report becomes available:
      • R1595
      • RD1305 *
      • R1596
      • CRDS66 *
      • R1597
      • AUST11 *
      • R4597
      • R1598
      • R4598 *
      • CRF76 *
      • T2091 *
      • RD1306 *
      • R4599 *
    2. Items arising:
      1. Hb has had a couple of experiments recently where data were lost because the delay through the DBBC and Mark5 was unstable and drifting. The only solution seems to be power-cycling the DBBC. Please keep a close eye on the delay difference. Documentation on what to look out for and how to monitor it is here. See the section “clkoff reading is drifting or far from the maser-GPS offset”.
      2. Hobart 26m : We are experiencing occasional formatter problems which Jamie suspects are due to timing distribution issues. Further investigation is needed (action: Jamie, Brett)
      3. On one or two experiments recently we've been getting close to module capacity or just going over. More care needed to make sure modules are big enough (action Jim, Jamie)
      4. Sometimes we send Hb or Ho data to Japan for Ultra-rapid experiments. Sometimes we forget to notify observers that they are on, and, as the procedure files are slightly different, no data are sent on the network. Ultra-Rapid experiments should be tagged in the schedule and observers notified (action Jim)
      5. The Ke control room needs an internal light that can be turned on/off remotely so observers can read the Mark5 module VSNs at night. (Action Brett, Martin)
      6. Yg earthing has been changed recently (following Brett's maintenance visit, completed July 31) and there's been a great improvement. However there were multiple clock drifts/jumps during R4599 and another one after setup for CRF77, but before it started, then again at ~04:15 UT (0.03 us). Please continue to watch out for clock jumps and note times. More discussions with MOBLAS staff needed to try and improve things.
  2. Roster
    1. Please let Jim know if you have any questions
    2. the account has a non-standard password. Ask Jim, Jamie if you need it.
  3. Recent software, hardware changes
    1. Tsys with caltsys and monit3.
      • We are now using caltsys as the command to obtain Tsys at all three sites. Use the program monit3 (run from a terminal on pcfs[hb|ke|yg]) to see the output. Documentation is needed on the wiki to describe how it works and what the numbers mean (action Jim)
      • Log monitor should be updated to provide a Tsys summary (Jim)
      • Note that S-band at Hb has bad interference in the upper two S-band BBCs and the broadband S-band Tsys values are badly affected by RFI too
    2. End-of-experiment message and module usage
      • Operators, please edit the comments file before sending so that the VSN of the module that was actually used is correctly shown. The script that pulls the VSN out of the log gets confused by the multiple module switching during setup for test recording, VSN checks etc.
  4. Operational issues
    1. Are Yg clock jumps back? See above
    2. 26m formatter jumps. See above
  5. Q & A
  6. Next meeting : 10 Sep at 2 PM
/home/www/auscope/opswiki/data/pages/operations/minutes2013_08_29.txt · Last modified: 2013/08/29 05:10 by Jim Lovell