GBT Operations & Commissioning Meeting
AGENDA
Activities List
We are soooooo close to finishing!!
All of the machining finished Tuesday morning, and Continental has demobilized.
Satcom checked the level of the final areas, installed wear plates, and grouted the sections yesterday.
Liquid epoxy was injected into some of the voids and debonded areas yesterday. That work continues today and tomorrow. After allowing for curing, the telescope should be ready for scheduling on Monday morning.
The stairs have been re-installed, and the baskets have been removed. There are no restrictions on elevation angles.
All azimuth and elevation motors and their brake packages and tachometers have been PM'd and are in service. The full system was run yesterday and today, and there are no faults.
We were able to put the S-band project onto the telescope starting on Tuesday evening. They had some issues with the changing power levels as the Galactic Center drifted by. They have modified their observing techniques to handle this. They also had one instance of Astrid freezing up.
Last Week
=========
Observations for proposals
GBT07A-060
Next Week
=========
Observations scheduled for **
GBT07C-067 [ B] Helene Courtois
Bulk Motions of Filaments in the Local Universe
GBT06B-037 [ B] Joel Weisberg
Probing the Small-Scale Structure of Molecular
Gas with Pulsar B1641-45
GBT07B-006 [ B] Fernando Camilo
Studying the magnetar XTE J1810-197
GBT07B-008 [ B] Nissim Kanekar
The nature of damped Lyman-alpha systems, as
traced by their spin temperatures
GBT07A-060 [F B] Julia Deneva
S-band Drift Search for Transients and Pulsars in
the Inner Galaxy
** Scheduled as F-ixed, P-rimary, B-ackup
Contact Information for 09/13/2007 - 09/27/2007
=======================================
Proposal PI Bands Email [NRAO contact]
---------- ------------------ ----- --------------------
GBT07A-089 Fernando Camilo 8 fernando@astro.columbia.edu [Scott Ransom]
GBT07B-011 Dunc Lorimer 3 Duncan.Lorimer@mail.wvu.edu [Scott Ransom]
GBT07C-067 Helene Courtois L courtois@ifa.hawaii.edu [Rick Fisher]
GBT07B-014 Marta Burgay S burgay@ca.astro.it [Scott Ransom]
GBT07B-005 Sharon Montgomery L smontgomery@clarion.edu [Frank Ghigo]
GBT07B-006 Fernando Camilo S fernando@astro.columbia.edu [Scott Ransom]
GBT07B-007 Nissim Kanekar 8 nkanekar@nrao.edu [D.J. Pisano]
GBT07B-008 Nissim Kanekar 3 nkanekar@nrao.edu [Frank Ghigo]
GBT07A-060 Julia Deneva S deneva@astro.cornell.edu [Scott Ransom]
GBT07A-072 Lisa Wei L wei@astro.umd.edu [Frank Ghigo]
Scheduled hours [backup]
========================
Category/Month-> August September
Astronomy ~ 241 8 [573]
Maintenance ~ 210 17 [068]
Test & Comm ~ 294 655 [031]
Un-assigned ~ 0 40
Proposal Checkouts #[hrs]*
=========================
Awaiting checkout - 0[0]
Active checkout - 0[0]
On Hold - 0[0]
Schedule - 76[3212]
Completed - 491[6289]
* All but completed queue applies to GBT only proposals
Current backlog of Reg & RRS proposals [hours prior to 07B*] = 1168
[2005:369(14), 2006:355(17), 2007:444(21)]
Backlog includes 59 hrs of monitoring projects
182 hrs of vlbi projects
Total time to discharge [hours] = 6518
Includes 286 hours++ of monitoring (not Large or Spec) after trimester 07B
2807 hours of Regular & RRS proposals
3317 hours of Large proposals
43 hours of Track Refurbishment proposals
352 hours of VLBI proposals
* Includes projects that are on hold for trimester 07B
++ Time is counted in other break down as well. 07B
- Prime Focus 1 is repaired, calibrated, and ready to install next week.
- Ku Band instability appears to be LNA related, testing is ongoing with removal highly likely.
- K Band is now cold.
- C Band retro-fit continues with hardware construction going as planned.
Digital Group Status 25-AUG-07 THRU 31-AUG-07
***Operations, Problem Summary***
No significant events to report this week.
***Maintenance***
Active Surface...
No work was done on the Active Surface this week.
***Development***
CICADA (Advanced Digital Backends Program)...
Specifications for the NGCUNPB have now been placed on our CICADA wiki for review and approval.
Spectrometer LTA Re-design...
- All LTAs in Quadrants 0 & 1 have been upgraded (a total of 4).
- Quadrants 2 & 3 should be complete by 07-SEP-07.
PTCS...
Preparations are being make to install another accelerometer set at the holography reference horn location. Design for the required mount is nearly complete, our old inventory of parts has been reconciled, and all remaining parts are on order.
ALMA...
On-going efforts are continuing fairly smoothly on the ALMA front.
***Plans For Next Week***
- Continue GBT Spectrometer LTA upgrade program...
- Continue work on NGCUNPB project, Phase 1...
- Complete design of mount for new accelerometer set...
- Continue ALMA efforts as required...
Randy
We are in the sixth development cycle of 2007. Please see the PlanOfRecordC62007 for all of the division's assigned activities.
Operational and user support was very light this week.
- 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. Sponsor is actively working on testing numerical results using test program. Continued to work with sponsor on testing. No issues identified with the new PFM5 yet, but a term seems to be missing in the antennaCharacterization database expression in the current Gregorian model.
- MRs under development:
- Port Holography Manager to Linux (ModificationRequest1C307)
- Alpha version of Linux manager is working. Building simulated data stream against which to perform more thorough testing, per MR. Building unit tests.
- 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:
- MRs ready for sponsor signature:
- MRs being written:
- 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.
- Control of Subreflector Nodding by Astrid (ModificationRequest2C407)
- Currently waiting on checker signature. Ready for sponsor signature shortly.
- Indicate Subreflector Position in Data (ModificationRequest4C507)
- Written except for one possible item that would be useful to test during if possible. The checking step can begin now.
- Implement GBTIDL Reduction Procedure for Subreflector Nodding (ModificationRequest5C507)
- Another round of feedback send back to Ron and others.
- Ka Manager Changes (ModificationRequest1C507)
- Merge Zpectrometer code branch into main trunk (ModificationRequest15C507)
- Written. Still needs Andrew Baker's signature. Then will be ready for CCC review.
- Mustang Manager Meta-MR (MasterMustangManagerMr)
- Links all of the sub-MRs together. The PCI initialization worked with just a minor tweak. Full testing of the PCI related parameters will be performed shortly. We've started looking at and documenting the basic data acquisition/parsing stand alone C++ parser.
- Data File Stream Upgrade (ModificationRequest7C507)
- Mustang Crate Control (ModificationRequest16C507)
- Crate Control MR still under negotiation. Brian is making progress in understanding key parts of DFB control 'mapping', and MR may have all requirements soon. We have coded most of the necessary low-level serial port commands. This week confirmed that serial port commanding code works by creating an NSTEP param for the manager, changing this value, and seeing the value from the parser agree - i.e. we can command the DFB's!!!
- Mustang Tower Control (ModificationRequest14C507)
- MR approved by sponsor (though 1 or 2 simple requirements are missing). 95% of low-level code complete. Need to add Ygor Manager parameters next.
- Tabled MRs:
- 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 - Mostly project management related activity this week. Finished first draft of agile work break down structure for software products.
- Create SRS for PST Administrative Functionality - We are iterating with Carl to refine requirements. Carl is back from vacation; we will start again in earnest next week.
- Evaluate GBT Data Handling Status & Future Options - No work this week because Bob focused on Ka work this week.
- Mustang Support - We added script to load the PCI driver on host computer (green) boot up.
- PTCS Support - Providing support as needed.
The servo room network upgrade has been completed. SDD report that all seems to be well.
PTCS -- PTCS Team
- Engineering
- Pointing
- Plans are in place for recommissioning observations beginning this weekend. See this http://wiki.gb.nrao.edu/bin/view/PTCS/RecommissioningCalendar?
- We have identified a few inconsistencies in the form and implementation in one of the thermal terms of the azimuth pointing model, as well as a confusion in alidade temperature sensor labels. To clarify all this, the contents of Project Note 25 (the thermal terms of the pointing model) is now being recast and moved into Project Note 53, which presently describes the geometry of the gravity terms and track model terms. In the M&C system, the corrections (which are a function of mount position) will be implemented in the equations stored in the database read by the Antenna Characterization manager. This decision allows the addition of other mount-angle dependent terms which Kim is now reintroducing. Hopefully this will lead to some small improvement in ultimate performance.
Quite a bit to report this week.
1. After working with Ray Craeger and finding that all the new 8-bit Spigot code somehow managed to get left out of the release, I tested the new 8-bit 800MHz mode via Astrid and all looks grand. On Monday we used S-band to drift through a known MSP and it looked great. With Paul Demorest we compared the profile to one made with GASP and they were very similar. Will be great for future S-band pulsar projects (and globular cluster pulsar timing).
2. Randy, John and I cleaned up the specifications for the new pulsar backend project. Paul was in GB yesterday trying to start learning the system. And it seems like Brandon will be working part time on the Stage I development (which should be a big boon to getting Randy, Jason, and Paul spun up). We may be converging on a name for the new beast as well. I think we like GUPPi. Green bank Ultimate Pulsar Processor. Opinions?
3. Julia Deneva's drift-scan S-band observations this week using the new 8-bit Spigot modes have had some issues. The biggest problem is that the Spectrometer and/or Spigot keeps clipping the zero-lags when the telescope gets close to the Galactic Center. Since Tsys changes dramatically, maybe this isn't too surprising. We've tried several "solutions" involving changing the Convertor Rack attenuator settings and balancing the IFRack periodically, but the Spigot seems to be easily knocked out of calibration by doing these things. Her data from last night was almost completely clipped (however, we didn't know this until after this evenings observations were complete). Maybe we need to rejuvenate the cursed AutoLeveler?.... (time passes) Actually, I just got off a long phone call with Julia and things tonight looked pretty good. By manually balancing the IFrack at strategicly timed intervals, she managed to observe through the Galactic Center with only about 10 sec of clipping in total. There was tons of RFI early in the evening, though.
MIT/LL 43m Project -- Glen
- 43m Mechanical and Drive systems in good shape, thanks to good continued maintenance.
- Some troubles with 43m control system this week. Not sure of the problem yet. Occurring at the rate of 1 or 2 spacecraft tracks missed per day. GB Ops has done a good job of getting us restarted after each hang-up.
- Otherwise normal spacecraft tracking.
- Pointing test results for GPS trajectories also somewhat marginal at low elevations. Some pointing offsets < .5 arc-min, others as large as 4 arc-min. Need to develop a test plan more completely next week.
K and Ku were cooled down. A preliminary checkout of these receivers was performed. K checked out OK. Ku, however, had intermitent power instabilities in the LCP of feed 2.
PF1 is still under repairs. Carl removed all 450 MHz observing from the schedule and the 350 MHz feed will be installed once PF1 is ready.
Q-band was taken off the telescope this week.
-
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 27 Remove Q-band from telescope to investigate high Tsys in one channel.
- 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: Re-install Q-band and do receiver checkout.
- 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
- Thanks to all for help with VSOP-II meeting. The visitors asked that we thank all for hosting the meeting. - Glen
-- RichardPrestage - 30 Aug 2007
Revision r1.13 - 31 Aug 2007 - 14:54 GMT - StevenWhite
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