GBT Commissioning and Operations Meeting 08 August 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 Minutes 1. Az Track Status -- Bob A. We have received a proposal and cost quotation from SG&H for phase 2 of the finite element analysis. We are working out the detail over the next few days. No other milestones or developments. Discussion: Bob added that the 4 remaining replacement wear plates will arrive this week. Rich wanted some clarification on what Phase 2 meant and Bob explained how Phase 2 involves a 3-d model. Bob also went on to describe some of the results from the structural inspection. He outlined how the quality of the caulking at some joints is allowing water to seep behind the caulking. Bob is interested in determining we have to inspect the system as often as is currently in our plans. 2. Observing news -- Ron Observing this week, like the last few, have mostly been Zeeman experiments with the Spectral Processor. And. like the last few weeks, the major source of lost time has been the Spectral Processor. Typically, in a 12 hour shift the SP will crash two to four times. The Converter Rack has also been "hanging" in "activating". This week, problems associated with GO have been adding up more than usual. Typical lost time is anywhere from 1/2 to 1 1/2 hours per 12 hr shift. Discussion: Rich described a test where he ran the SP for 16 hours without a failure. The best guess for reducing the Sp problem is to change the data cables between the SP Rack and the Gemini computer, approximately a $700 fix. 3. Spectrometer status -- Rich The spectrometer had one reported problem this week. Braatz had problems with observations using more than one quadrant. This problem was actually found a day before he distributed his observing summary. It was traced to an intermittent problem on an LTA card. The card has been replaced. A second problem was fixed before any observers noticed. Power would not stay on for more than a fraction of a second. This was traced to a capacitor that had failed short and was loading down a power supply. The capacitor, or what was left of it, was replaced and the problem fixed. Development of the 32 MHz LTA upgrade continued. A few cards have problems with the higher speed clock for the microprocessor. The problems are not consistent from one card to the next. A large, unnecessary, delay in the pulsar spigot's reset routine was removed from the firmware. The measurement of the reset times of all microprocessors in the system was completed. A modification request was submitted to the SDD to take advantage of the new hardware reset capability. The measured reset times were included in the modification since the system will have to wait at least that long after a reset before issuing more commands. A new "tweak test" developed by the SDD was tested this week. This test measures errors as a function of LTA read-out delays, which is required in setting these delays when LTA or correlator cards are changed in the system. After a bit iteration, the test closely matches the results of the original tweak test provided by Jeff Hagen and Escoffier. With a little additional cosmetic work it will be ready for prime time. Testing of the pulsar spigot continued. This week a command which temporarily changes the data format to allow the measurement of lag statistics was tested. Some problems were found and forwarded to Escoffier. With regards to the Spectral Processor, specifications were generated for cables which would replace the existing cables and "A/B box" between the spectrometer and data acquisition computer, gemini. The new cables should reduce the frequency of data errors into gemini by reducing crosstalk and noise. Plans for next week: Vacation and single dish school The following week a lot of effort will be put into an observing run with the pulsar spigot and pulsar software requirements. Rich and Holly Discussion : An impressive amount of work. 4. Spectral Baseline, Front-end, and IF work -- Roger New Heliax cables for the Converter Racks have arrived and are being installed. I have no test results as yet. The K-band upgrade proceeds. The new HFET bias wiring checked out OK. Only one error was found and quickly corrected. Final cleaning and assembly of the dewar is now underway, and the first cooldown should happen within the next few days. Work on the 1cm Receiver proceeds. On the mechanical side, fab drawings for the dewar cylinder and heat shields have been submitted to the shop, and fabrication is progressing. Cardcage wiring is about three-quarters done, cal control circuitry design nears completion, and work on the microstrip frequency multiplexer is cranking up. A real worry has been the 26-40 GHz square-law detector diodes. The vendor has had materials and/or fabrication problems that have dragged on for months, but they now assure Galen that our units will be shipped next week. We are attempting to schedule the removal of the C-band receiver August 20-26 for some tests on the feedhorn related to the baseline investigation, and for cryo maintenance. There also has been frequent interaction related to the UPenn bolometer project, including planning for a trial cooldown of the 300mK refrigerator system in the GBT receiver room, perhaps in late September. RDN 8/7/03 Discussion: Roger wasn't at work so his report was read. Again, an impressive effort. 5. Software status -- Nicole Single Dish Development IPT #46 - Friday, August 8, 2003 We are now ending week 6 of a 7 week development cycle, meaning the development cycle will be complete at the end of next week. 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. The Project Charter for DCR Improvements has been successfully completed, and will be awaiting review by the sponsor, after which Ray will be giving a presentation on the Charter results immediately following the summer school. Several small-scale DCR issues were solved in the process of compiling the Charter, and these will be fully tested prior to release in mid-August. Also, a Project Charter has been started for the Caltech Continuum Backend, for which we anticipate software to be developed by the end of the year. The new spectrometer quicktest has been developed, internally tested, and now waiting to be sponsor tested. 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. Operational support this week has included a fix for the feed defroster, maintenance on the old Configuration Tool (as requested for PTCS experimentation), a fix for the Active Surface Manager crash issue, and some changes to the showSurface GUI (for the Active Surface) that make it easier to turn the power supplies off and on. These two items will be sponsor tested early next week. Also, it was discovered Thursday evening that the spectrometer is starting a second late. This issue is now being investigated, and we hope to find a resolution sometime today. Regression tests are scheduled for Sunday, August 17, with a release to follow on Monday, August 18. -NMR Discussion: Ron asked about Nicole's meeting with Heiles and Co. concerning GO and control software. Nicole said there were no surprises in the issues they brought up. Most of their comments were already on the list if things we'll be addressing. Some discussion on the cause of the recent 'Slew To' problem in GO. Toney described how the problem is not receiver related, as originally thought, and only arises for observations like Heiles and Co. where they tightly incorporate a "Slew To" in their observing procedures and when their are small moves. Most casual users of "Slew To" would not have an issue. Ron noted that the reason for the "Slew To" in the Heiles observations was the need to properly balance the system levels. Since proper power levels is an issue for many kinds of observing, we should soon start a project that explicitly finds a practical solution. 6. Schedule -- Carl Last Week ======== Observations for: GBT02C-009, GBT02C-010, GBT02C-046, GBT02A-002, BF073, GBT03B-045 Completed: GBT03B-045 August ===== Scheduled hours: Astronomy ~ 343 Maintenance ~ 193 Tests & comm ~ 196 Un assigned ~ 12 September ===== Scheduled hours: Astronomy ~ 217 [backup ~ 78] Maintenance ~ 147 [backup ~ 48] Tests & comm ~ 240 Un assigned ~ 117 Carl Discussion: Dave Hogg asked for details on the 'backup' time in the September schedule. Carl explained the primary observing is PTCS tests with various L-band and local projects as backups. 7. Project scheduling -- John August 4th Planning Meeting Minutes Rm 241 10:00 A.M. 0) Observer comments F. Y. Zadeh 2C19 and 2B6 Summary: Very successful Problems: Spectral Processor, software inadequacies, education telecon snafu We discussed the problems, including a mixup in getting set up to do a video telecon from the GBT control room. The solution at this point seems to be that any requests for special videocon or other computer/network configurations must be sent to helpdesk@gb.nrao.edu for action. This will avoid the problem of it slipping through the cracks. It should be noted that the loss of our dedicated 1/2 time network person will make it more difficult than ever to respond to this type request. The spectral processor has been worked on, and seems to be better. We are going to replace the cables from the SP to the computer, as the grounding is weak. 1) This week's schedule Nothing remarkable 2) Next week's schedule Telescope at access for Monday morning. 3) August Observing Schedule discussions None 4) September Observing Schedule discussions None 5) GBT development planning Project Management 6 weeks review meeting set for Monday, August 4, 1:30-4:30) -- Nicole, Richard, Kim, and Dennis to meet prior to this and work out the remaining problems remaining from requests to the shop and software Discussion of Latest Ideas We discussed the Phase Cal project, and Jody's antenna safety proposals. We decided that the Phase Cal project will be placed on the electronics CME project page, and the other proposals for antenna safety will be worked by Operations. Discussion : John was on vacation, fishing someplace nice, we hope, so his report was summarized. We discussed the lost network time reported by the Zadeh. Ron mentioned that the incident report was incomplete. A pulsar observer was trying to use the GBT remotely when the network went down and neither he, the operator, or the 'friend' of the observer knew about or remembered the planned outage. More communication and planning would have helped. Carl noted it's hard to predict when the loss of the network will affect observing since observers, even when they observe locally, rely on the Internet. Carl will look into whether the plans for a second route out of Green Bank are in place. 8. Any other business