Meeting Information

  • 1600 UT (1000 MDT)
  • AOC 317; IP: 146.88.16.8; phone: +1 575-835-7370

Agenda/Minutes

News, Travel, Visitors (McMullin)

  • Overall status: In D configuration (all antennas moved as of the 26th; end of D is 27 December). All correlator hw resource issues resolved and ready (Q4 pair 15 is currently
reserved for testing purposes).
  • Key dates:
    • 26 Sep - 27 Dec: D configuration
  • Visitors:
    • Michiel Brentjens: 11 Jun - 11 Nov (Holography; characterizing polarized beams)

Hardware status and updates (Langley, Perley, Rupen)

  • Array (Perley/Langley):
    • Antennas: EA25 out.
    • Receivers:
      • EA24 for first L-band solar capable Rx.
      • Perley: RF Switch testing ongoing.
      • Calibration (Perley): Gain compression/expansion ongoing (Hayward).
  • WIDAR (Rupen):
    • Notes (Rupen/Sowinski): On the sky acceptance document completed.
  • Computing (Robnett):
    • Notes:

Software status and updates (Butler)

Commissioning Group Reports and Test Planning

  • NOTE: Please cc me on submitted tests so that it can be assigned the appropriate priority!

Commissioning priorities for the week (McMullin, Chandler); Note: Change for Mondays in D configuration - dedicated to science operations/planned commissioning tests.

  • Mon
    • 1000-1700: Testing/software development time
    • 1800-0900: Science operations and testing
  • Tue:
    • 0900-1700: Testing/software development time
    • 1800-0900: Science operations and testing
  • Wed: Maintenance day
    • 0630-1700: Maintenance operations
    • 1800-0900: Science operations and testing
  • Thu:
    • 0900-1700: Testing/software development time
    • 1800-0900: Science operations and testing
  • Fri (not-yet-a-holiday):
    • 0900-0900: Science operations and testing
  • Sat-Sun
    • Science operations + planned testing

Issues Affecting Science Observing:

  • Correlator: [Rupen/Carlson w/ Momjian/Sault] V stokes issues.Status
  • Correlator: [Pokorny/Rupen/McMullin] time mislabeling in SDM data (non-synchronous operation between correlator dumps and CBE can require additional 1/2 integration time padding for online flags). .Needs close-out testing (Michael-update activation time testing).
  • Correlator: [Clark/Carlson] Delay rocking across bands. (October)
    • Array: [All] Zoo of other effects (some data are very good, some still seeing antenna-based IF/Polarization issue).

Testing This week/soon

  • Holography.
  • Subarrays: cleanup.
  • Stage 2 mixer testing to relax sub 128 MHz BW grids
  • Correlator: Rupen: S-band shadow testing
  • Spectral line: Roy/Dhawan: HI High resolution bandpass testing
  • Baseband edge/filter rolloff.
  • Sub-band dependent fshifts.
  • Array: *; Individual issue sleuthing.

Commissioning Groups

1000 -- 1150 MHz:  Pretty grim.  This is the zone of aeronautical
beacons (DMEs and radars).   The lines are all narrow, with an abundance
of 'holes'.
   1170 -- 1260 MHz:  Extremely strong and broad emission (GPS, and
others).
   1260 -- 1350 MHz:  Mostly empty, with a few (~8) narrow emissions
(radars, I think).
   1350 -- 1525 MHz:  Mostly empty.
   1525 -- 1610 MHz:  Zone of Death!  I doubt we'll ever be able to use
this region.
   1617 -- 1640 MHz:  Another deathly zone.
   1640 -- 1675:  Open
   1675 -- 1695:  Many RFI sources.
   1695 -- 1930:  Almost completely clear!
   1930 -- 1990:  Much RFI -- cellphones, I think (?)
   1990 -- 2180:  Mostly clear.
   2180 -- 2200:  Very strong RFI (geostationary satellites, I think).
   2200 -- 2310:  Mostly o.k., some strong RFI between 2225 -- 2240.
   2310 -- 2355:  Satellite radio. Completely hopeless!
   2355 -- 2500:  Mostly open, with a few (~8) narrow 'lines'.
   2500 -- 3580:  Mostly clear, but with strong RFI near:  2740, 2800
-- 2820, 3315, 3420 -- 3460 MHz.
   3580 -- 4200:  All of this span is heavily polluted -- I think this
is due to satellite downlinks for TV.
   4200 -- 6110:  Almost entirely open.  *** 5990 -- 6015 had strong
RFI in March 2010***
   6110 -- 6170:  Strong RFI throughout.  *** This span was entirely
open in March 2011***
   6170 -- 6360:  Open.  *** 6240 -- 6270 had strong RFI in March 2011***
   6360 -- 6420:  Strong RFI throughout.  *** This was entirely open in
March 2011***
   6612 -- 6618:  Strong RFI (which was also present in March 2011)
   6618 -- 6772:  Open.
   6772 -- 6777:   Strong RFI (also present in March 2011)
   6777 -- 7400:  Almost clear of RFI.
   7400 -- 7720:  Generally clear, but with scattered, generally
narrow, RFI.
   7720 -- 8000:  Clear of RFI.
    • 4-band (Owen):
      • Notes:
    • Adv: Low band (Owen):
      • Notes:
* Scheduling/Rapid Response (Claussen/McMullin): Link: https://safe.nrao.edu/wiki/bin/view/EVLA/RapidResponseObserving
      • Notes:
Sept 08 test:  I was testing to see how long it took to phase up using various scan lengths (8, 5, 10, 15 sec).  I would do an autophase only on the first scan then have 9 scans where there would be autophase & apply phase and delay, then I would apply only for a few minutes.  I would always start with the autophase only.  That test worked great, the array seemed to phase up in 3 scans, no matter what the scan length.  If you look at the delays there seems to be an adjustment after 3 scans and then another small adjustment after 3 more, but the phases look great after the first adjustment.

Sept 17 test: I was testing if you could phase up in 3 scans only and if applying the delay continuously would even be better.  So every 5 minutes there would be a 3x10sec autophase loop but the delay and phase was applied continuously, except for the first autphase loop.  For the first autophase loop the first scan is autophase only, and then 3x10scans autophasing and applying. In this test it looks the first autophase loop is the only one that does anything, after *2* autophase scans the baselines are phased up.  Unfortunately, for this test, most of the baselines are rock steady at 0 phase for the entire half hour after the first autophase loop.  But antenna 1 doesn't get to source until after the first phasing loop and it never phases up; and a few baselines wander away from 0 as much as 90 degrees and are never fixed.  I looked at the *.evla script and it is says what I expect, i.e., at the start of each autophase loop has these lines
autoph0 = subarray.registerPhasing('A-0')
autoph1 = subarray.registerPhasing('D-0')

So there are two differences between the first and second test, 1) the first had more autophase scans and 2) the first stopped applying the delay at for the first scan of the autophase loops.  There is nothing weird about the antennas that wander from 0 other than being longer baselines

    • Adv: Astrometry (Mioduszewski):
      • Notes:Update
  • Calibrator Models
    • Notes: Reduction underway; Ka/S coming very soon; others to follow.
  • HPC (Bhatnagar/Owen/Golap):
    • Notes: ~500 GB data set obtained. Issues noted when filling switched power.
  • Imaging (Ott/Golap):
    • Notes: Takahashi/Ott working on mosaic needs in PST/OPT. Document under review.
  • Algorithm (Bhatnagar, Owen):

RSRO/ECSO Reports

RSRO A configuration status: https://safe.nrao.edu/wiki/bin/view/EVLA/2011AConfiguration

Individual reports (updates)

Misc:

Demo Science Status

AOB

-- JosephMcMullin - 2011-09-13
Topic revision: r2 - 2011-09-28, JosephMcMullin
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