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GBT Operations & Commissioning Meeting

17 August 2007

AGENDA

• Upcoming Activities -- Carl
• Az Track, Antennae Report -- Bob
• Observing News -- Ron
• Scheduling Status -- Carl
• Microwave Electronics Status -- Steve
  • Operations
  • Development
• Digital Electronics Status -- Randy
• Servo Systems Status -- John and Bob
  • Operations, Problem Summary
  • Development
• Software Status -- Amy
  • Operational & User Support
  • Modification Requests/Tasks
• Computing -- Chris
• PTCS -- PTCS Team
• Pulsar Related -- Scott
• MIT/LL 43m Project -- Glen
• Commissioning Plans -- Ron
• Any other Business

Upcoming Activities -- Carl

Az Track, Antennae Report -- Bob

Machining of the distorted areas of the base plates has started, and is giving favorable results. Grouting of the other base plates was completed Wednesday. A total of 8 base plates and 4 splice plates remain to be grouted after the machining of their surfaces is completed. Continental's weld group has staffed down to 1 welder to support the machinists, and SATCOM will also begin staffing down, as they now complete dressing of the grout areas, filling of some voids, removing imperfect grout, and general clean-up. We've lost some time tonight due to the lightning, but we expect that we can release the telescope by the 31st, perhaps sooner.

Lightning tripped the network last night, interrupting GBT observations and a 140' tracking pass. Efforts to restore service are in progress as I'm writing. John Shelton and I are on night shift monitoring and supporting the machining effort.

Observing News -- Ron

We're taking a break from the pulsar survey since PF1 was uninstalled on Monday. I've looked into whether we can execute the S-band summer shutdown project but, unfortunately, the desired elevation doesn't match with our elevation restrictions. Until PF1 is repaired, we're trying to use the telescope for testing but aren't filling the time. We're open to other suggestions.

In other news, we gave Q-band a receiver checkout and, as Gary's email stated, found 1 of the 4 channels having high Tsys. The Tsys of the other channels look fine.

Scheduling Status -- Carl

Microwave Electronics Status -- Steve

Operations

Development

Digital Electronics Status -- Randy

***Operations, Problem Summary***

No significant events to report this week.

***Maintenance***

Active Surface...

• Summer maintenance activities are now winding down with the following accomplishments: 41 Actuator problems fixed, 18 motors replaced, 18 LVDTs replaced, 4 modules repaired, and 1 cable spliced.
• Due to scheduling and access constraints, this leaves 9 under-the-surface problems and 6 acuator room problems yet to be taken care of.

***Development***

CICADA (Advanced Digital Backends Program)...

• FYI... "CICADA" stands for "Configurable Instrument Collaboration for Agile Data Acquisition" (A creative product of Glen's imagination!)
• Orders have been placed for computers and networks for CICADA development
• Our two summer interns (Brandon Rumberg and Patrick Brandt) have now finished their terms with us; having completed and released a working design for Glen's "Transient Event Capture 3000" instrument.
• A draft project charter for the Next Generation Common User NRAO Pulsar Backend Project (NGCUNPBP, AKA Scott Ransom's "Dream Pulsar Machine") has now been placed on our CICADA wiki.
• Project WBS, Schedule, and Effort Request documents for the NGCUNPBP are expected to be placed on the CICADA wiki Monday of next week.

Spectrometer LTA Re-design...

• The 1st article, upgraded LTA has now been successfully installed and tested in the GBT Spectrometer with no ill effects.
• Long-standing problems with the LTA test fixture, which have plagued this project from the outset, have now been resolved. This should allow us to proceed from this point with an aggressive program aimed at completion of upgrades to all 8 LTAs in the GBT Spectrometer by the end of September.

PTCS...

• A large order for parts has been placed which will allow us to build 5 spare units each of: Temperature Sensors, Accelerometers, and GDAQs
• Some preliminary engineering efforts have been carried out regarding the installation of another Accelerometer set near the vertex (where the holography reference horn is to be installed).

ALMA...

On-going efforts are continuing fairly smoothly on the ALMA front.

***Plans For Next Week***

• Continue to work on program/project planning documents for CICADA projects...
• Prepare for and participate in Paige Ireland's visit...
• Begin accelerated GBT Spectrometer LTA upgrade program...
• Continue ALMA efforts as required...

Randy

Servo Systems Status -- John and Bob

Operations, Problem Summary

Development

• PLC interlock system being installed for testing

Software Status -- Amy

We are just starting the sixth development cycle of 2007 which can be viewed at PlanOfRecordC62007. We released M&C v7.5 and GBTIDL v2.2 yesterday, August 15. The integration test reports for the release are available for your perusal (August 7, August 9) as are the release notes.

Operational & User Support

Operational and user support was very light this week.

Modification Requests/Tasks

• MRs ready for release:
• MRs ready for sponsor testing:
  • Implement PFM5 revised pointing/focus model (ModificationRequest1C407)
    • Note - This MR was released as part of M&C v7.5 to simplify sponsor testing. PTCS is actively working on testing numerical results using test program created as part of MR.
• MRs under development:
  • Port Holography Manager to Linux (ModificationRequest1C307)
  • Modify Peak Finding Algorithm for Pointing/Focus Code (ModificationRequest4C207)
    • FrankGhigo and ToddHunter have settled on GaussianFilter as preferred method. However, since this approach changes the resultant pointing offset values, deployment of the selected approach will be postponed until after the new pointing model is implemented this summer.
  • SCCU Servo Changes (ModificationRequest1C806)
    • Although the code is working, we have found that commanded velocity spikes occur during normal observing. To date this has not been a problem since the hardware filters out the spikes. However with the hardware modifications coupled with this MR, the spikes will corrupt the intended operation of the friction compensation. John is working on modeling a different methods of deriving the velocity commands.
• MRs under CCC review:
  • Add DIO interface to Linux Holography Manager (ModificationRequest12C507)
    • Revising MR to reflect recent team discussion about interrupt characteristics of new interface card, and the effects this will have on software design.
• MRs ready for sponsor signature:
• MRs being written:
  • Control of Subreflector Nodding by Astrid (ModificationRequest2C407)
    • Decision has been made to extend ObservingAPIBuildingBlocks to control subreflector movements, this MR needs to be modified describe which scan procedures will require this capability.
  • Subreflector Nodding Observing API Building Block (ModificationRequest17C507)
    • This MR is a spin-off from ModificationRequest2C407 and describes the building block SubMotion for controlling the subreflector in general and SubNod for nodding specifically. A first draft is about 3/4 complete.
  • Ka Manager Changes (ModificationRequest1C507)
    • GalenWatts is working on MR.
  • Correct Labeling of Ka-band Hybrid-Switched Signals (ModificationRequest3C407)
    • One small issue in the MR remaining and then it will be ready for sponsor signature.
  • Create Pyrgeometer Manager (ModificationRequest2C207)
    • No progress.
  • Mustang Manager (ModificationRequest6C507)
    • This MR will be broken up into many smaller MRs. We will be working next week with Brian Mason and other project team members to scope out crate/parameter/cabling specs. We will also be working with Simon Dicker next week to scope out the housekeeping requirements.
  • Data File Stream Upgrade (ModificationRequest7C507)
    • No progress this week.
• Tabled MRs:
  • Add Two New ScanTypes: FivePoint and Circle (ModificationRequest1C706)
• Other Activities:
  • Complete Pointing Processing Description Memo - Work being performed as part of implement model 5 task above. Needs some cleanup to include focus tracking.
  • Dynamic Scheduling - Little or no effort this week.
  • Create SRS for PST Administrative Functionality - We are iterating with Carl to refine requirements. Carl is away on vacation this week and next.
  • Complete Documentation of Cross-Polarization Changes - Complete.
  • Evaluate GBT Data Handling Status & Future Options - No work this week because Bob is on vacation.
  • Mustang Support - We are providing support as needed.
  • PTCS Support - Currently working on subreflector sampler data drop-outs and retesting subreflector actuators.

Computing -- Chris

PTCS -- PTCS Team

• Servo Systems
  • Meeting held to review sub-projects and project plans
  • Interlock system being installed this week for testing
• Pointing
  • We are trying to perform a validation test of the new M&C code that implements PFM5. I received a MATLAB data structure from Kim on Tuesday with the results from 700 pointing scans. While converting it to ASCII tables for input to Joe's pointingTestUtility, I uncovered a typo in an equation in PN25 (thermal aspect of pointing model, specifically the alidade temperature relation). Fortunately, the M&C code is implemented correctly, but Kim had followed the typo in creating his structure. He sent me a revised structure yesterday, which I hope to start running through the pointingTestUtility later today.
• Surface/Holography
  • Agenda being developed for an informal OOF workshop
• Instrumentation
  • No activity

Pulsar Related -- Scott

MIT/LL 43m Project -- Glen

• Normal spacecraft tracking
• Working on a real-time trajectory interface with MIT's Lincoln Labs. We will circulate the plan to team members and get comments before implementation.
• Starting to plan budget for capital outlays to use unspent funds from FY 07.

Commissioning Plans -- Ron

My understanding is that the Mustang tests went well. The receiver was removed yesterday. Galen distributed a very promising report on the recent Ka/Zpec tests. CCB/Ka tests also went well. On Monday's commissioning/resource meeting, the decision was made that we'll be mounting the single-channel version of Ka-band in September.

The track delay has not affected our achieving various commissioning milestones. So far, the consequences of the delay are a loss of astronomical observing in September and a delay in the PTCS work associated with remodeling the pointing. I doubt that the problems with Q-band will ripple into our commissioning plans.

• July 17 through Aug 1 : L-Band refrigerator work. Must be completed for Governor's school
• Aug 1 through Aug 31 (originally Aug 17, the end of track shutdown) : Reinstall Q-band; pump and cool.
• Aug 6 : Install Mustang
• Aug 6 through no later than Sept 7 : Mustang tests
• By Aug 13 (Originally Aug 10) : Decision as to whether we will use this fall the one polarization configuration of Ka-band.
• By Aug 10 (1 week before end of track shutdown) : Install S-band and X-band. The receivers will already be cold when they are installed. Due date is set by the end of the track repairs and so may slip forward or backward. Installing by Aug 10 is preferable since that will give us time for receiver checkouts during the track shutdown.
• By Aug 31 (originally Aug 17, the end of track shutdown) : receiver checkouts for S-, X-, and Q-band. Includes pulsar checks of new S-band filters. Two nighttime 4 hr sessions per week, the LST is to be determined.
• Aug 31 - Sept 15 (originally Aug 17 - Aug 30, the end of shutdown to 2 weeks later) : Contingency test time for any remaining S-, X-, and Q-band receiver checkouts. One nighttime 4 hr sessions per week. Dynamically scheduled.
• Aug 31 (originally Aug 17, the end of track shutdown) : start of PTCS recommissioning of the track
• No later than Sept. 3 : K-band pumped and cooled
• No later than Sept. 10 but no sooner than 1 week after K-band is cold: K-band receiver checkout. Dynamically scheduled.
• No later than Sept 7 : Mustang removed
• Sept 14 : End of PTCS recommissioning of track
• Week of Sept 17 or Sept 24 : Install Ka-band. Contingent on Aug 10 decision.
• Before Sept 24 : Ku-band removed to make room for Zpec. No need to cool Ku until it is reinstalled (Nov?). Contingent on Aug 10 decision.
• Week of Sept 24 or Oct 1: Install Zpec. Contingent on Aug 13 decision.
• Week of Sept 24 : Q-band project checkout (8 hrs)
• Sept 23 - Sept 30 : SDD software tests for Oct 3 release
• Week of Sept 24, Oct 1, and Oct 8: Ka-band/Spectrometer recommissioning. Contingent on Aug 10 decision. One 8 hr sessions per week of A-class weather (nighttime, dynamically scheduled).

• Week of Sept 24, Oct 1, and Oct 8: Ka-band/Spectrometer recommissioning. Contingent on Aug 10 decision. One 8 hr sessions per week of A-class weather (nighttime, dynamically scheduled).
• Oct 1 - Oct 13 : Zpec commissioning, A and B weather, dynamically scheduled. Contingent on Aug 10 decision.
• Oct 7 - 15 : CCB/Ka testing, A-class weather (nighttime, dynamically scheduled).
• No later than week of Oct 15 : Install C-band .
• Oct 18 : Decision as to whether to continue using the Ka-band single-pol configuration. Whether to schedule 100 hrs of Zpec observing. Whether to remove Ka and convert back to old configuration. Whether to proceed with Ka/Spec/CCB observing.
• Oct 21-Nov 2 : C-band astronomical commissioning, C-class weather
• Nov 2 : C-Band observing can start
• Nov 2 : Decision on how to proceed with traditional holography. Which receiver will we remove? When will tests start? Do we need to cut a mounting plate?
• Nov 2-15 : C-band baseline tests, C weather, and X-band baseline tests, B weather, dynamically scheduled.
• Week of Dec 3 : C-band removed, Mustang installed
• Dec 7 : Telescope at access for Mustang
• Dec 8 - week of Jan 15 : Mustang tests -- dynamically scheduled, A weather, nighttime.
• Week of Jan 21 : Mustang removed, C-band installed
• Feb 3-13: SDD software tests for Feb 13 release

Any other Business

-- RichardPrestage - 16 Aug 2007