Date: February 19, 2020

Time: 11 am Mountain, 1pm Eastern
Phone: 434-817-6468 ext 228113#
Room 152, Socorro

Attending: Jim, Justin, John from USNO, Walter, Mark
USNO: Chris, Matt, Stewart, Nicole, Bruce, Alan, Philip, Andy

VLBA Observations
    • Daily Observation Report (N-series)
      • PT began experiencing what we believe to be S-band RFI on January 13 or 14, first seen by operations in the post-observing check of N20014. Initially believing it to be an RDBE problem a reobs was attempted and when then also looked bad a third observation was made with LA substituting for PT, but for unknown reasons no data was recorded by LA. USNO correlation confirmed lots of H-code problems in S-band. A few more zeros/no fringes than normal, but still finding fringes most of the time.
      • MK two of the X-band channels have low amplitudes and need to be removed from correlation in the W-series. N-series channels don't overlap with the W-series and it's not being seen in N-series. Not RFI. Phases good in first two channels but then go bad. Clock? RDBE?
      • There's another issue where N-series is having to drop one X-band channel from PT when pointing to the west. Likely RFI.
      • X-band RFI might be from Spacelink? VLA has been seeing some recently.
    • Other Intensive Observations
      • W-series observations underway, will probably run through mid-March 2020.
        • Last one appears to be on March 16th.
        • Due to recent PT-MK issues may want to extend/redo some sessions. Will need to analyze the affected runs more.
      • "Holiday" intensive observations at MK
        • Will be substituting MK for Kokee on federal holidays in 2020 such as 1/20/20 and 2/17/20.
        • Formerly referred to as "emergency" intensives.
        • Project code for this observation will be IYYDOY.
      • A MK-WZ observations will run on Saturdays beginning December 7 2019 through March 7 2020.
        • Project code for this observation will be QYYDOY.
        • Will involve a new post-observing procedure for operators to copy the data to correlator in Japan.
        • No Q-projects for MK listed in the IVS schedule for March, stops with run on Feb 22nd then returns in late September (possibly - awaiting approval.)
      • O-series test of HN-OV baseline continues
        • Will run simultaneous with the N-series observations but will not interrupt other observing.
        • Some access problems due to loss of web portal, considering if they should go public like the other series'.
        • Any end date in sight? No. Data still useful. Possibly expand to include another baseline like SC-BR or SC-LA (avoiding S-band RFI at BR.)
        • Possible oscillation/tracking issue at HN recently detected.
    • Post-Monthly Report Review:
      • Three requested observations didn't get run in December for a total of 21 hours of backlog for January. All three were observed in early January.
      • Sowders replacement observation did not use any of its eight hours in January.
        • Probably should start calling this something other than "Sowders replacement observation".
      • UG003T had numerous issues during its run so a replacement observation UG003T1 was scheduled just in case it proved to not meet requirements.
      • The pre-monthly request listed a UJ003 project but it was actually UJ002. The request said 26 hours but it only used a little over 21 hours.
    • Pre-monthly request
      • The monthly time allotment has been increased to 200 hours, request does not reflect this. Updated version came out with correct hours.
      • W-series intensives end 3/16.
  • Open issues
    • UH006 (Sowders replacement) has been demanding much more than their monthly allotment of time and not providing observing files in a timely fashion, disrupting operations and interfering with our ability to schedule other observing.
      • Communications breakdown among all parties, Megan unaware they'd gone directly to us asking for the extra time after an initial query from them about the possibility of it. Requests should go through USNO for anything past the allotted 8 hours.
    • USNO emails to ut1 list are not being forwarded along to other USNO people.
      • Not an issue with the mailing list itself, something a couple levels up from USNO in the network.
      • Mail is being blocked at the Dept. of Defense level, working with them on that. Have not instituted any workarounds yet.
      • Some things have been tried, didn't work. Waiting on clearer instructions for some more things to try.
    • HN-OV baseline is more precise than any of the others USNO has data for, not sure why. Plus with all the recent problems showing up at PT maybe when fiber available to HN switch the N-series to them and PT-MK to the O-series? HN fiber probably won't be in place until late summer/early autumn (August?)
        • Mayb also add BR to the F-series for testing of additional baselines. Put it in the next one to see how it looks (S-band RFI might be a problem.)
    • USNO needs to renew support contract for MK fiber.
      • Paperwork has gone through. No update.
    • Networking Support Contract: Contract will be renewed for FY2020.
      • Renewed or not? USNO will check into it. No update.
    • Correlator Refresh Contract: Correlator was assembled in November.
      • Lustre filesystem and second set of nodes still awaiting installation in January. Done?
      • Not done. Procurement problems have delayed it until late March.
    • USNO is moving to new ingest data server and IP address is not working even though it's on NRAO's whitelist. USNO reports attempts to transfer data to the .179 address does not work. Looks like problem might be firewalls at USNO end?
      • Started approval process to fix problem.
    • Transition to Mark6 recording system is underway, including 4 Gbps capability.
      • Tests for transitioning to the higher data rate, perhaps with C-band, will be considered. (Though C-band has ionosphere problems.)
        • Mark Claussen will provide some 4 Gbps setups for USNO to look at for the tests.
      • Might be some USNO funding for more Mark6 disk drives/packs. NRAO doesn't currently have a need for more disk packs but that could change in the future once more 4Gbps observing starts.
    • New IVS session code naming structure (long-term issue)
      • There is likely to be a change to format of the IVS "session code", but maybe not until 2021. As the USNO works to make the VLBA intensives look like IVS sessions we want to discuss what impacts such a change might have on this effort. This particularly relates to the 'exper_name' in the .vex files.
      • Intensives are all now using the xYYDOY naming format (ie, N20001, O20001, etc)
      • New IVS codes will be similar to existing codes but perhaps slightly longer, for example "NYYYYDOYNN". USNO & Goddard have discussion about it, length will be more than six characters. NRAO has already used some seven character length codes (such as N20014B) without it causing any problems.
    • VLBA able to participate in CONT2020 (Nov-Dec 2020). Won't be a full 15-day session, maybe a "mini-CONT" of around five days. (Long-term issue)
  • Next regular telecon meeting on March 12.

-- JimOgle - 2020-02-03
Topic revision: r7 - 2020-02-24, JimOgle
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