GBT Operations & Commissioning Meeting 23 May 2003 AGENDA 1. Az Track Status -- Bob A. 2. Spectrometer status -- Rich 3. Commissioning and Observing Checkout News -- Ron 4. Spectral Baseline, Front-end, and IF work -- Roger 5. Software status -- Melinda / Nicole 6. Data reduction report -- Joe McM (or proxy) 7. Project scheduling -- John 8. Observing schedule -- Carl 9. Any other business PRELIMINARY REPORTS 1. Az Track Status Dennis and I are in Savannah, GA observing the welding and machining trial. The work is going around the clock, so we've been staying late/coming in at odd hours to see important milestones. As in any development project, there have been things to work through, but they are still exactly on the established schedule this morning. The welding is complete on the top weld, and they are remachining the side welds this morning , and finishing all welding today. Ultrasonic inspection and dimension checks are tomorrow. They are also tearing down equipment and loading it to mobilize for the work in Green Bank June 2. Dennis and I will be back either late Friday night or Saturday morning. In other efforts: - I have laid out draft safety and shutdown instructions, and will bring those to the planning meeting Tuesday. - We have reviewed the structural inspection bids, and Carol is proceeding with a recommendation of award. -- RA 2. Spectrometer status This week has been working on increasing microprocessor clock from 16MHZ to 32MHZ. System Monitor has passed tests on the bench and in the system after upgrade to 32MHZ. It will be put back in the system next week, and monitor its behave. LTA board has pass some, and failed some tests on the bench. A firmware upgrade was installed in the system monitor. It now waits on the correct interrupt to read analog voltages, currents and temperatures. However, it also waits 5 msec, which is way more than required for the conversion to complete. Therefore the predicted robustness enhancement from this firmware change will not occur. Pulsar spigot firmware has been upgraded to permit synchronization with the site 1 PPS. It was found that hardware upgrades will also be required to make this work. These are now in progress. A second upgrade to the system monitor was checked this week. The purpose of the upgrade is to allow the VME computer to reset the System Monitor computer. Hardware modifications were successful. There are still some problems with the firmware. Some time was spent learning Microwave Office. This program will be useful in the design of the upgraded test fixture. There are now two predominant failure modes in the spectrometer. The first is that data from quadrant zero is not present after an interrupt from this quadrant. I have requested that time tags be added to the log entries associated with interrupts being received. This will help identify whether we are dealing with spurious interrupts. I have also requested to be called when this occurs to look at certain monitor points and the health of the system's microprocessors. I have not received any calls. The second problem deals with set up. We often get "Failure to load CCC Xilinx personality" in quads 0 and 2. I cannot reproduce this problem using the engineering port. I suspect this will require a joint hardware/software debugging sessions to solve. Plans for next week (comments appreciated!). - Update documentation related to this week's upgrades - Continue work on 32 MHz upgrade - Continue work on system monitor reset capability - Continue learning Microwave Office -- RL & HC 3. Commissioning and Observing Checkout News Commissioning this week was business as "usual". o Glen checked out four proposals, all of which can now be moved to the "Can Be Scheduled" list. Two more proposals will be checked out on Friday o Karen had one session of Spectrometer checkout, all of which, according to Karen, has a frequency problem of unknown cause. She will be on the telescope Friday morning trying to determine the cause. o We supported three observing proposals and the numerous, enthusiastic visitors we had from Socorro. Next week, we expect we'll be working on observing support, a few remaining proposal checkouts, our last session for spectrometer checkout until fall, and, if the hardware is repaired, an holography experiment. -- RM 4. Spectral Baseline, Front-end, and IF work Passive thermal stabilization of a Optical Receiver 4-way divider had no discernable affect on the 60MHz baseline ripples. Additional testing with pads at various locations was done this week. Analysis of the data is not yet complete, but it does appear the problem is related to isolation between the channels. We continue to see that terminations on three of four OR outputs gives the best performance. Initial thinking about an affordable way to add buffer amps has started, as that may prove to be the final solution. On or about June 2, we plan to remove the K-band and Q-band receivers for an upgrade to the K-band amplifiers, and to prep the Q-band for next season. Assuming the track shutdown goes as scheduled, we will also pull the X-band receiver down for lab baseline testing. -- RDN 5. M&C Software status Software Development Division #37 - Friday, May 23, 2003 We are ending week 4 of a 5-week development cycle, which will culminate with the release of M&C v.3.14 on 6/4/03. The plan of record which shows goals for M&C v3.14 is available at http://tryllium.gb.nrao.edu/images/POR_May03.pdf. Key tasks this month include finishing up software work on the spectrometer in response to the recent platform change, a batch of active surface items in support of PTCS, continued EMS development and analysis tasks including review of GBT configuration algorithms from a control systems perspective. 15 out of 15 MRs have been written and are approved, 1 MR has been dropped due to costs outweighing benefits, and 1 MR has been dropped due to changing requirements that preclude development on schedule (this task is in support of active surface hardware troubleshooting). Of the 13 remaining MRs, 2 are still under development and 9 are ready for sponsor testing (this includes all EMS-related tasks which are still being tested by Kim to support the first trilateration experiment using EMS). The remaining 2 MRs, involving antenna work in support of PTCS, have been approved and development has begun. Some operational support was provided for troubleshooting during observations, most notably with respect to user interfaces. Additional time was spent in consultation to the Penn Array project. Two small Requests submitted to the Project Office were fulfilled this week, including a fix to a data format in the holography FITS file, and adding 2 new samplers and 2 new control parameters to the LO for electronics. Despite some technical difficulties at the outset, the first of two FQL Tutorials was held on 5/21. Another FQL Tutorial will be held in the NCR the first week of June for those who were unable to attend, or would like to hear the same stuff again. -- NMR 6. Data reduction report 7. Project scheduling May 19th Planning Meeting Minutes 0) Observer comments None received this week. We discussed some informal comments from commissioners and support scientists. We also discussed asking the support scientists for a particular project to comment on the projects. It was stressed that this was *not* meant to replace the observer's comments, but to capture additional information, or in the case where the observer will not give any comments, to at least record the general feel of the staff as to the relative success of the project. Nicole had some specific questions that she wanted the observers to answer. She and Ron will discuss this. Carl will support this effort by modifying the comment form as required. 1) This week's schedule Spigot card tests scheduled for Thursday. Otherwise, nothing noteworthy. 2) Next week's schedule Thacker will be here for a test run on their ALMA tests. 3) June Observing Schedule discussions 2 projects for drift scans were put on the schedule during the track shutdown. It was noted that there may be work going on by the contracter and NRAO emplyees at ny time day or night during the track shutdown, and so there may be some RFI consequences. 4) July Observing Schedule discussions PF-2 will be commissioned in the first 2 weeks of July as previously planned. 5) 6 month plan review No activity yet on minutes of last meeting. 6) AOB a) RFI Several discussions took place on RFI. With the advent of the low frequency observing season, we will be paying much attention to RFI. There is a great deal to look at: 1) The JL shielded rooms are completely overhauled 2) The servo RFI improvements are done 3) The network equipment shielding is nearly complete. 4) Receiver room components are starting to appear on the RFI screen. This gives us reason to suspect that the receiver room shielding is not up to par. We plan to test this out, and identify any problems. 5) We will need to start identifying sources of LF RFI around the site and getting rid of them. ASince the shielded rooms are repaired, and the network equipment is shielded, we may be able to significantly quiet the site by shutting down all the electronics at night. Tests need to be done to confirm the feasibility of this. 6) See "C" below for additional RFI survey information b) Roger Norrod asked to pull K band on June 2nd for the summer. X band will also be pulled down June 2nd for two weeks for in-lab baseline tests. The Q band receiver will be pulled and stored for the summer. c) Frank Ghigo writes: I'd like to request some time for a new RFI survey at the prime focus bands. The MIT satellite radar group that is planning to do some experiments with the GBT later this year wanted us to do a survey of 410-460 MHz in a different way than we have done these surveys in the past. The request is to point the antenna near the horizon, say at 5 degrees elevation, and sweep around the horizon. We would collect spectra every half degree. The process would take about 1 hour to complete a scan. This would be of general benefit to all of our low-frequency observers, not just the MIT group. So I would like to request we schedule this in blocks of 2 hours (setup plus observing time), and have one session in the middle of the day, and one in the middle of the night, and do this for each of the 4 prime focus bands. We would of course observe the whole frequency range of each receiver, not just the portion that the MIT group is interested in. I would suggest we might do two bands in each session, so allow about 3-4 hours in the day, and 3-4 hours at night (after 1am for example), and do this on two separate days. i.e., 12-16 hours total. It would be useful to repeat the survey at 6-month intervals. -- frank This will be done. Scheduling has begun for it. Frank and Glen will cooperate on it. -- JF 8. Observing Schedule Last Week ======= Observations for: GBT02C-059, GBT02C-034, GBT01A-014, GBT02C-063, GBT02A-015, BT069, GBT03B-041 GBT02C-063 was completed May === Remaining time: Astronomy ~ 100 hours Maintenance ~ 37 hours Tests & comm ~ 95 hours June === Shutdown ~ 227 hours Astronomy ~ 401 hours * Maintenance ~ 190 hours Tests & comm ~ 118 hours * 215 hours are scheduled during the track work shutdown period as background projects when the GBT cannot be moved July === Astronomy ~ 305 hours Maintenance ~ 218 hours Tests & comm ~ 221 hours August ===== Astronomy ~ 296 hours Maintenance ~ 192 hours Tests & comm ~ 255 hours ** ** includes some time for Single Dish Summer School -- CB 9. Any other business