GBT Operations & Commissioning Meeting 18 June 2004 AGENDA 1. Az Track and Telescope Status -- Bob 2. Observing News -- Ron 3. Scheduling Status -- Carl 4. Frontends, IFs, and Spectral Baselines -- Roger 5. Spectrometer Status -- Rich 6. Software Status -- Nicole 7. Project Planning Status -- John 8. Any other Business PRELIMINARY REPORTS 1. Az Track and Telescope Status As for the track activity: * Plate 23 developed a 2" crack. When lifted, the extent on the bottom side was about 9". We replaced it yesterday. Along with the crack, 5 bolts on the inside bolt circle were broken or broke when turned to remove. They were located midspan. * Art, Dennis, and I have modified SGH's proposal for additional studies and will be forwarding it to them today for discussion. * The materials lab have completed prep on the samples from plate 45 and we should have a report on it soon. * We have asked Gadsden Tool Co. for a quote and delivery time for 4 additional wear plates. There is heavy demand right now for steel products. The 4340 plate material should be in Gadsden by the end of this month, after a delayed delivery. * Other activity prevented further work on the track this week. Other activity: * We found a buckled angle brace under the walkway from bearing to bearing last week. Further inspection this week found a cracked weld in a gusset to a structural member. Yesterday, the brace was replaced, and a temporary suspension cable installed. Art, Dennis and I are working to redesign this support. * The structural inspectors have found two welded cover plates over openings that appear to have been broken by freezing. These will be repaired (minor items). -- RAA 2. Observing News We supported 6 observing projects, one of which was a radar run, in 17 observing sessions. We also supported observing API, calibration, and PTCS tests. In total, 100 hours of astronomy and 20 hours of tests were scheduled. Lost time amounted to about 5% of the scheduled time. The majority of the lost time this week was due to Spectral Processor software (4 hrs) and GFM (1 hr). All other lost time amounted to 1.25 hrs, almost all due to software. We had some luck in the timing of when the X- and S-band receivers warmed up. A day earlier or later would have been disruptive to the observing plans. The average setup time this week was lower than typical at about 35 minutes per observing session. We can expect next week to be as light as this week since only 5 observing projects are scheduled, many of which are in large blocks. -- RJM 3. Scheduling Status Last Week ========= Observations for proposals GV017 , BB187 , GBT02A-046, GBT04B-015, GBT04B-017, GBT04B-007, GBT02A-017 Completed proposals GV017, BB187, GBT04B-015 Next Week ========= Observations scheduled for GBT02A-041 PI Robert Rood Stalking the Cosmic 3-Helium Abundance GBT04B-035 PI Fernando Camilo Spectral and Temporal Studies of the Two Pulsars in the J0737-3039 System GBT02A-046 PI James Braatz Monitoring a Maser Disk in Mrk 1419 GBT02B-005 [P] PI Farhad Yusef-Zadeh Search for Positronium Recombination Maser Line Emission Toward the Galactic center GBT04B-007 PI Casey Law A Study of the Galactic Center Lobe Scheduled hours [backup] ======================== Category/Month-> June July August September Astronomy ~ 327 322 [029] 301 [014] 330 [152] Maintenance ~ 220 208 214 210 Test & Comm ~ 170 174 [017] 129 [023] 162 [053] Un-assigned ~ 3 40 100 18 Proposal Checkouts ================== Awaiting checkout - 0 Active checkout - 5 On Hold - 6 Schedule - 66 Completed - 187 Current backlog [hours prior to 04B*] = 1699 Total time to discharge [hours] = 2681 * Includes projects that are on hold for trimester 04B -- RCB 4. Frontends, IFs, and Spectral Baselines The cryogenics group serviced two receivers this week. A compressor failure caused the X-band to warm-up on Sunday evening, and since that refrigerator was due for maintenance the opportunity was used to replace it. An unrelated refrigerator failure on the S-band receiver also required service. Norrod, Fisher, Balser, Maddalena, Minter, and Ford had a meeting reviewing recent baseline investigations, and discussed possible future tacts. On the engineering side, the immediate emphasis will be mitigation of the "60MHz" ripple induced by Equipment Room temperature variations, and then on understanding the receivers' noise temperature ripple. Development of observing and analysis procedures accounting for receiver noise variations needs to be done in parallel. Work continues on the Q-band and Ka-band receivers. R. Norrod 6/17/2004 5. Spectrometer Status Spectrometer Report 10 Jun - 17 Jun 2004 *****Operations***** Only one significant problem was reported this week. The spectral processor had several episodes of unscheduled stops. This was caused by multiple problems, both hardware and software. The hardware problem was traced to a failed EDT data acquisition card in gemini. Software problems were traced to recent, subtle, changes in the code. The software group can explain these in better detail. *****Development***** Some timing tests were run on the spigot as part of a small project to characterize the absolute delay of the spigot vs operating mode. Also begun was a firmware modification to acknowledge the receipt of coefficients by the spigot cards. The LTA design review was held Monday and went reasonably well. Small deficiencies in the design were spotted and most have been corrected already. Another outcome of the review was a decision to investigate the cause the lag drop-out problem before calling the new LTA design complete. If the cause is buried in the present LTA design, then this will assure that the problem will be fixed by the re-design. *****Plans***** Spigot: - Continue work on spigot card firmware modification. The software will make it possible to know that calibration constants have been successfully loaded. - Continue work on absolute timing of spigot data vs mode. LTA replacement: - Continue to incorporate changes from the design review. - Continue searching for the cause of the lag drop-outs. Lag drop-outs: - Continue work on finding the cause of 1024-lag-long pulses in acfs. -- Rich 6. Software Status Single Dish Development IPT #85 - Friday, June 18, 2004 Today ends Week 5 of 6 in the fourth development cycle (C4) in 2004. The Plan of Record which shows what you can expect in these releases is available from the wiki at Software.PlanOfRecordC42004. Documentation showing results from our integration and regression testing, and other previous cycles release information, can be found at Software.SoftwareReportCentral on the wiki. Most work this week has focused on readying the items on the POR for integration tests, which begin on Saturday. Additional work has including tying up loose ends with configuration management of IDL code and the JNI GPIB interface. Also, the issue seen by the PTCS group where the Archivist fails to archive has been reliably reproduced and investigation is underway. It is likely that resolving this problem will be a requested maintenance task for the upcoming cycle. Observing API tests have been conducted for a few hours each day this past week. The API is now reliably producing GO FITS files and quick look data can be viewed within GFM. Friday's tests will evaluate dynamic corrections driven from the API, and use of a prototype SB executor GUI which may provide the flexibility that observers demanded in last week's meeting, namely, that new SBs can be created on the fly by selecting lines from a previously executed SB. Operational support over the past week has included: + Errors with memory overloads in the Spectral Processor have been identified as too many, too large parameters being set at once on a single board that can not cope with the load. As a result, Grail has been improved to manage communications with the single boards more parsimoniously than managers on other platforms. This should prevent single board limitations from bringing down the system until all managers are ported to Linux. --NMR 7. Project Planning Status MINUTES June 14, 2004 Planning Meeting Rm 137 10:45 A.M. [0] Observer comments & operator log items resulting in lost time: Operator's log comments Significant failures this week stemmed from: Computing: data and scratch disks filling up (no time lost). - Chris is cleaning up space Software: Spectral Processor Quicktest failure Spectral Processor hung in aborting/stopping Spectrometer data interrupt failure Scan length with extra zero caused Antenna to reboot (processing time at start of scan caused communications to timeout). - Known or one-off problems Electronics: Spectral Processor EDT board failure N.B. Both of these SP failures should have been found *before* they caused lost time. We need to be more diligent about making sure dormant backends are OK before they are needed. -- JF We agreed the Operator should be asked to run quick-test on Spectral backends that are not in use. RMP/BA to agree details. 5 MHz/1PPS problem Compressor trip caused X-band receiver to warm up. This is to an extent "just one of those things". However, we did discuss the fact that replacement of the model-22 refridgerator on both C and X-band receivers is explicitly planned as part of the "receiver refurbishments" project, which is on hold due to lack of money and effort. This decision could be revisited, although some other activity would then have to be dropped. Active Surface and Structural Temperatures problems - no time lost. Workarounds/fixes in place. Telescope/Servo: Weather, Az Brake fault Misc: Arecibo transmitter / code generator failures Other Problems from Observing Reports: G. Langston: GFM does not do RA-DEC peaks. An explicit decision has already been made that GFM will not support RA-DEC peaks. This might be added as part of a general purpose off-line analysis package. [1] Resource calendar schedule conflicts and discussions" Day #1 - 5 OK. Note maintenance all five days! Bob raised the possibility that inspectors might like antenna at bird-bath. If so, this would have to be worked around plans already in place requiring access. [2] Observing Schedule discussions Time on Wednesday evening nominally allocated to PTCS tests. Some time on Sunday morning still available. [3] GBT development planning Meetings Schedule Project presentation meeting June 15th, 10-12 Cycle 5 planning meeting, June 22nd, 10-12 Quarterly Reports due July 5th, so June 25th for individual contributions. [4] AOB None --RMP / JMF 8. Any other Business