GBT Commissioning and Operations Meeting 25 July 2003 AGENDA 1. Az Track Status -- Bob A. 2. Observing news -- Ron 3. Spectrometer status -- Rich 4. Spectral Baseline, Front-end, and IF work -- Roger 5. Software status -- Nicole 6. Schedule -- Carl 7. Project scheduling -- John 8. Any other business Preliminary Reports 1. Az Track Status Az track: No significant milestones or developments this week. Lee, Dennis, and I are discussing the Finite Element Analysis Friday morning. Operations: Structural Inspection is in progress. No significant findings. The telescope will be in the access position Monday morning for the PF1 receiver installation, then moving to 83 degrees upon its completion. -- RAA 2. Observing news Support has concentrated this week into three major areas: PF2 commissioning, observer support, and Holography. PF2 commissioning has been summarized in various e-mails. Tests included: o Two RFI survey, one at night, the other during the day (Ghigo). For the most part, RFI is prolific with nighttime better and few RFI-free contiguous MHz. Frank can report on these results. o Focus as a function of frequency (Maddalena), the results of which I sent out as an e-mail last Friday. There is a slight dependence on frequency that observers will have to take into account manually since there isn't a way currently for the telescope control system to track focus with frequency. Also, the PF2 focus position is very different than that for PF1. Since the antenna manager probably does not know whether PF1 or PF2 is in place, the observer will have to make sure they do not use the default, PF1 focus offset when using PF2. o Long DCR integrations to check on the 1/F characteristics of the receiver and whether broadband observations integrate down. o Pointing and beam shape -- all looks OK with small pointing offsets and good beam shapes. o Scal/Tcal/Tsys/bandpass/efficiency data still needs to be reduced (Langston). The only experiment we didn't have time for was a long spectral-line observations. We may want to talk about the problems we had with safe-hold modes and software limits encountered during the PF2 commissioning time. Problems were not only for the PF2 mount but also for the Azimuth drive where Tim came very close to hitting a hardware limit without a software limit kicking in first. Here's a quick summary of the notable items for the four projects we supported this week. o We need to buy more IDL licenses for observers use, especially with the new data-reduction directions we are moving toward. o Most projects used the Spectral Processor but there is no indications that the SP failure rate is any higher than in the past. Thus, last months issues may have been a fluke. o The startup for proposal 2C46 on Monday was very shaky with two hours of lost time due to manager failures, various restarts, etc. Karen's e-mail showed a very painful night. None of these problems reoccurred on subsequent nights for this project. o Karen has encountered some documentation and parameter-setting issues within GO. o She is also having to work around the undesired firing of the noise diode by the Spectral Processor between scans and when balancing the IF Rack. o Wed. night the antenna's date was off by an exact 3 years, which only affected the 'indicated' telescope's position so no substantial time or data were lost. Joe was able to fix this but the operators didn't log any details as to the cause or fix. The holography backend, for the same satellite I used in early July, had the same phase drop out problems. The problem did not exist when I went to a 10db-weaker satellite. Thus, the 'problem' is either something intrinsic to the satellite or a digital overflow of some kind somewhere. I have some ideas on how to investigate the cause a bit further. Then I tried making a 128x128 map and am only partly through the steps of checking the sanity of the data. I should have more to say on the holography results sometime next week. -- RJM 3. Spectrometer status The spectrometer has been used very little for astronomy lately. There's been little progress on determining the cause of the DMA errors. With regards to the noisy spectrum reported by Langston at last week's meeting, it was found that there were obvious steps in the correlation function of several (13 out of 270) integrations. They showed up in the average of the correlation function as well. Software to look for these steps would be useful. It is not clear whether these steps were due to software or hardware errors. The minimum dump time was also requested. For each quadrant, the minimum dump time is 85.2 ms * number_of_bins, as limited by the hardware. The software can read the data faster than the hardware can write it. However, there may be some other limits due to software file writing, etc. The final touches were put on the hardware reset this week. It was demonstrated to work properly in the system and has been documented. A few misadventures on the way to this goal caused a fair amount of time to be lost repairing burnt wires on a board! One upgraded LTA Board has been tested on the system thoroughly (different self tests and scans), it seems work fine. But self test on the bench still has problem. Hopefully, to get together to discuss about it next week, and debug it with Ray when he come to Green Bank (probably next week) can make some progress on it. Ordered more 32 MHZ oscillators for the rest of LTA boards. Some modes were broken in the upgrade to 3.15. Luckily I stumbled over a few during hardware reset testing and they were promptly fixed by Mark. Plans for next week. - Continue work on LTA upgrade - Start work on documenting pulsar programming requirements. - May need another spigot test run to clean up a few items before the scheduled observing run. -- Rich & Holly 4. Spectral Baseline, Front-end, and IF work No significant new baseline observations were made this week. Phase-stable coax cables for the Optical Receiver to Converter Module connections are due by the end of July. Design of a package for a prototype LO2 buffer amp using a commercial MMIC chip nears completion. One of a mixer for possible use in the Converter Module upconverter spot has just been received and will be evaluated next week. The shop is well along on fabrication of the Ku-band waffle-iron thermal transition, but the job has been slowed by other priorities. Waveguide transitions for testing the new transition are in the CDL plating lab for electroforming. While PF2 was on the GBT for commissioning, various bugs that had accumulated over the past few years were worked out of PF1. It is scheduled to be reinstalled next Monday, and Gary is in the midst of new thermal cals and other checkouts. The K-band upgrade proceeds. New amplifiers and the associated wiring changes (fairly major) have been installed. The new wiring will be checked "hot" next week. The feedhorns are in the shop to have the waveguide flanges dressed, and the radomes are being redesigned to eliminate "puddling". The shop has also been asked to build waveguide cal standards to allow accurate measurements of the thermal transitions before the system reassembly is completed. We're shooting to do the first cooldown of the reworked receiver in the first week of August, and barring surprises GBT reinstallation near the first of September. Editing of the baseline internal report continues. -- RDN 7/24/03 5. Software status Single Dish Development IPT #44 - Friday, July 25, 2003 We are now ending week 4 of a 7 week development cycle. The next upcoming release of M&Cv3.16 is planned for immediately after the summer school, on or about 8/18/03. The Plan of Record for the current development cycle is available from the Project Office web site at http://tryllium.gb.nrao.edu/docs/POR/POR_July03.pdf. Activities for next cycle will include continued work on Data Export and Accessibility, the Ease of Use Initiative, PTCS activities, completion of the current phase for the Antenna Test Range software, and other continuing maintenance and enhancement activities including the addition of a new quicktest for the spectrometer. Work continues on preparing the Project Charter for DCR Improvements, and solving any small-scale DCR issues in the process. These will be fully tested prior to release in mid-August. The new spectrometer quicktest has been developed and is ready for internal testing, which will commence on 7/28. The 5000 samples per scan limitation on the DCR has been resolved, tested internally, and is currently undergoing sponsor testing. The issue with the DCR starting one second late has been resolved in development and is awaiting further internal testing. In support of the summer school, two data sets have been successfully imported into IDL from an SDFITS file containing GBT data, and are currently being reviewed by Karen for completeness and accuracy. Throughout the summer the possibility of compiling a single SDFITS file for GBT data is being explored in depth. SDFITS files have already been constructed for several DCR and spectrometer data sets, and have received preliminary evaluation by astronomers. By the end of the development cycle the goal is to have a memo in place that discusses the specifications for these prototypes, so that this can be reviewed by a wider audience as we decide whether to make this a production capability. Work is underway, and we anticipate meeting the deadline. Further progress is also being made on software for the Caltech Continuum Backend. Documents and test programs from Caltech are being reviewed and evaluated for completeness, and preparations are being made to write a new Manager for this device in one of the remaining three development cycles of 2003. The current phase of work on the Antenna Test Range will complete at the end of this development cycle as well, however, additional software work will be required in the fall if the new test range software is to be used. Problems have arisen handling a digital encoder for receiver azimuth position monitoring, and additional hardware has been built to simplify the problem. The software to handle this digital encoder will not be complete this development cycle, and is required to produce useful measurements from the receivers under test. -NMR 6. Schedule Last week ======= Observations for: GBT01A-057, GBT02C-023, GBT01A-007, GBT02C-046 Completed: GBT01A-057, GBT02C-023 July === Remaining: Astronomy ~ 117 hours Maintenance ~ 60 hours Tests & Commissioning ~ 4 hours August ===== Scheduled: Astronomy ~ 345 hours Maintenance ~ 193 hours Tests & Commissioning ~ 185 hours Not scheduled ~ 21 hours September ======= Scheduled: Astronomy ~ 72 hours (BU=16 hours) Maintenance ~ 148 hours (BU=48 hours) Tests & Commissioning ~ 210 hours Not scheduled ~ 290 hours Just started scheduling September. -- RCB 7. Project scheduling July 21st Planning Meeting Minutes Rm 241 10:00 A.M. Attendees: B. Anderson, C. Bignell, D. Egan, J. Ford, P. Jewell, R. Maddalena, R. Prestage, N. Radziwill 0) Observer comments None this week 1) This week's schedule No conflicts PTCS temperature sensor installation commences this week Structural inspections start today 2) Next week's schedule Maintenance days are cut short Wednesday and Thursday. 3) July Observing Schedule discussions SDD wishes to give up test time on the 31st of July. 4) August Observing Schedule discussions SDD will give up part of the time on August 2nd/3rd. SDD would like time on the 17th for pre-release tests 5) GBT development process and program proposal review Green Bank Project Management talk Tuesday 3:00 P.M. John will mail out a draft of the presentation to meeting attendees Tuesday morning for comments. Nicole will give John the project initiation table. Project Management 6 weeks review meeting set for Monday, August 4, 1:30-4:30) We discussed who should come to this meeting. It was decided that the project managers, project scientists, project engineers, and division heads should attend. All other interested scientists and engineers are invited to attend, as well. 6) AOB September Observing Schedule discussions We will plan to have 4 12 hour maintenance days in September, mainly to catch up on the painting, but also to allow PTCS installation work, active surface repairs, and other work cut short by the summer structural inspection access schedule to be completed before winter. PTCS might need as much as 1 day per week for observations. Richard will confirm this with Carl. October Observing Schedule discussions We will plan on 3 9.5 hour maintenance days for October, to be scheduled on Monday, Tuesday, and Thursday. Phil asked us to get our estimates and plans for the 2004 Program Plan in by Thursday. -- JF 8. Any other business