VEGAS Team Meeting

January 14, 2013


CALTECH, UC-B, & Columbia

Dan, Jayanth, Mark, Andrew


Jason, Ray, Marty, Anish, John, Paul, Scott, Randy, John

Meeting Notes:

Next Teleconference: January 21, 2012 .

VEGAS Mode Development Status:

Action Items:

  1. half part of the IF band has poor SNR. why? is it fixed already? how to fix?
    • Tests on cable integrity downstream of the RF splitter will be conducted during maintenance tomorrow.
    • The Gain/TSYS slope is probably not an issue if the spectrometer can be balanced for applied power levels
  2. the start up problem:
    • how often does it occur?
      • About 1 in 10 times
    • how quickly can we recover?
      • Quickly now there is code that flags of no data is being produced
    • how much observation time is lost)?
      • Not an excessive amount
    • how to fix?
  3. 16 bins of the spectra have poor SNR. (an FPGA design problem).
    • does this affect timing?
      • no
    • is the problem understood?
      • need to test with test pulsar
    • do we need to fix it before observations?
      • no
  4. valon locking problem.
    • Solved by a power cycle - inconsistent status between python GUI and laptop
  5. what else needs to get fixed before we observe?
    • 12 second gaps
      • after 'arm' command the counter increments - the time offset from the manager shows increasing and the jumps value at ~12 seconds
        • maybe missing data
        • or FPGA code
        • Anish will circulate with actual FPGA data and count plot
        • "Show stopper" unless this is well understood previous to observation
    • Two hour+ data collection (first test tonight)
  6. what tests should we do before we have enough confidence to start observing?
    • Test Pulsar
    • Known Pulsar - with gap to prove obs can be combined
    • Two hour+ data collection (first test tonight)
    • On-Off continuum obs for sensitivity

Other items:

-- MartyBloss - 2013-01-14
Topic revision: r2 - 2013-01-14, MartyBloss
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding NRAO Public Wiki? Send feedback