GBT Operations & Commissioning Meeting
AGENDA
- Busy several weeks for Track work, and it hasn't slowed down yet.
- Quotations for wear plates and base plates were higher than expected. We've exchanged a good many questions and answers and are looking to reduce the cost without changing designs. This effort continues.
- The request for quotation package also went out on Thursday. For most who only have to write a single page for a requisition and specification, you won't think this is a big deal, but the packages for work of this nature are 75 to 100 pages, plus drawings. Lots of good work by Carol, Jeff Cromer, Mike Holstine, and the team (Art, Dennis, Harry, and John Shelton).
- Phil, Art, and I were also involved in obtaining a proposal from a company to do project management. The cost was prohibitively expensive, so we will continue to look for ways to do this with NRAO internal resources.
- Next week, reps from Industrial Bolting Technologies will visit, and we will discuss bolts and tensioning equipment and obtain a quotation from them. We will also send out a RFQ packages for bolts, nuts, splice plate refurbishment, and tensioners. This will pretty well complete procurement quotations.
Over the last two weeks, we supported 23 different projects in 42 observing sessions. We also had 21 hrs of maintenance, 4 hrs of software tests, a 36 hr shutdown for Thanksgiving, 16 hrs of high-frequency commissioning, and 11 hrs of polarization commissioning. The average setup time was 19 minutes. The Ka-band tests were curtailed due to receiver problems that were summarized in Richard's e-mail and with more details available on the web.
I will discuss the lost time for the two weeks separately. During the 7 days of Nov 24-28, we lost 6.4 hrs, about 6% of the time assigned to astronomy. The major causes of lost time were:
- Scan Coordinator/Astrid/GFM weirdness : 1.4 hrs
- Message Mux crashing : 1.1 hrs
- Operator (Az drive not turned on) : 1.1 hrs
- Antenna Manager Software : 0.8 hrs
- CLEO/Window manager : 0.7 hrs
- Extended setups : 0.4 hrs
- Weather : 0.4 hrs
- Astrid : 0.4 hrs
I didn't see any follow up on the Scan Coordinator/Astrid/GFM issue. Some of the symptoms sounded to me like trying to point under bad weather conditions combined with software problems.
During the last week, lost time amounted to 9% -- I mean 0.9% 
or about 1.4 hrs of the time scheduled for astronomy and commissioning!!!! Only two classes of problems are notable:
- Astrid : 0.5 hrs
- Az Transducer fault : 0.4 hrs
- All others : 0.5 hrs
Last 2 Weeks
=============
Observations for proposals
BW083 , GBT05C-050, GBT05A-041,
GBT05C-051, GBT05B-042, GBT05A-011,
GBT05C-042, GBT05A-033, GBT05C-031,
GBT05B-011, GBT05C-043, GBT05C-022,
GBT05B-034, GBT05C-012, BT075 ,
GBT05C-023, GBT05C-034, GBT05C-046,
GBT05C-002, GBT05C-014, GBT04B-026,
GBT04C-029, GBT05C-009
Completed proposals
GBT05C-050, GBT05C-002, GBT04B-026
Next Week
=========
Observations scheduled for **
GBT05C-051 [ P ] Jim Braatz
A Snapshot Survey for H2O Megamasers in Nearby,
Luminous Galaxies
GBT05C-042 [F B] Scott Ransom
Timing the Binary and Millisecond Pulsars in
NGC6440 and NGC6441
GBT05C-031 [ P ] Amanda Kepley
Magnetic Fields in Dwarf Irregular Galaxies: NGC
4214
GBT05C-021 [F B] Marc-Antoine Miville-Deschenes
Characterizing Dust in High Velocity Clouds
GBT05C-034 [ P ] Seiji Kameno
Water maser tomography through molecular torus
of NGC 1052
GBT05C-056 [F ] Paulo Freire
A GBT S-band Globular Cluster Survey: Phase B
GBT02A-066 [FP ] David Hughes
Breaking the Redshift Deadlock: The Spectroscopic
Redshift of HDF850.1, the Brightest
Sub-millimetre Source in the Hubble Deep Field
GBT05C-058 [ P ] Tyler Foster
The Galactic Object OA184: Supernova Remnant or
HII Region?
GBT03C-012 [ P ] Jim Braatz
Follow-Up Observations of Extragalactic H2O
Masers Discovered with the GBT
GBT05C-038 [ P ] Geoffrey Bower
Searching for Radio Pulsations from Radio point
sources in the Galactic Center
GBT01A-005 [ P ] Barry Turner
A High-resolution Spectral Survey Of Tmc-1 At
Q-band
GBT05C-009 [ B] Gilles Joncas
GBT HI Observations of the DRAO Deep Field:
Determining Foregrounds for Planck
** Scheduled as F-ixed, P-rimary, B-ackup
Contact Information for 12/15/2005 - 12/29/2005
=======================================
Proposal PI Bands Email [NRAO contact]
---------- ------------------ ----- --------------------
GBT05B-042 Michael Kramer L8 mkramer@jb.man.ac.uk [Scott Ransom]
GBT05A-011 Scott Ransom S sransom@nrao.edu [Scott Ransom]
BK127 Kirsten Knudsen L knudsen@mpia-hd.mpg.de []
GBT05C-021 Marc-Antoine Mivil L mamd@ias.u-psud.fr [Jay Lockman]
GBT04C-043 Scott Ransom 8 sransom@nrao.edu [Scott Ransom]
GBT05B-023 Adrienne Juett SC ajuett@virginia.edu [Scott Ransom]
BT075 Andrea Tarchi K atarchi@ira.cnr.it []
BK114 Paul Kondratko K pkondrat@cfa.harvard.edu []
GBT05C-034 Seiji Kameno K kameno@hotaka.mtk.nao.ac.jp [Karen O'Neil]
GBT05C-023 Fernando Camilo S fernando@astro.columbia.edu [Scott Ransom]
GBT05C-056 Paulo Freire S pfreire@naic.edu [Scott Ransom]
GBT05C-046 Ingrid Stairs S istairs@astro.ubc.ca [Scott Ransom]
BB184 Jim Braatz K jbraatz@nrao.edu []
GBT05C-014 Katie Devine K devine@astro.wisc.edu [Ron Maddalena]
GBT01A-005 Barry Turner Q bturner@nrao.edu [Frank Ghigo]
GBT05C-018 Tim Robishaw L robishaw@astro.berkeley.edu [Toney Minter]
GBT05C-009 Gilles Joncas L joncas@phy.ulaval.ca [Jay Lockman]
Scheduled hours [backup]
========================
Category/Month-> December January
Astronomy ~ 384 [254] 332 [282]
Maintenance ~ 25 [051] 43 [060]
Test & Comm ~ 231 [018] 120 [021]
Shutdown ~ 36 0
Un-assigned ~ 69 250
Proposal Checkouts
==================
Awaiting checkout - 0
Active checkout - 1
On Hold - 24
Schedule - 49
Completed - 416
Current backlog [hours prior to 05C*] = 930
[2001:44(1), 2002:91(3), 2003:31(2), 2004:255(12), 2005:509(22)]
Total time to discharge [hours] = 2075
* Includes projects that are on hold for trimester 05C
Operational Issues:
The Motor Rack cryo pressure sensor started producing erratic data in some
channels. This is being investigated.
C-band refrigerator maintenance is being planned for the week of Dec 12.
Development:
3mm:
Fabrication, bending, and testing of the first batch of waveguide was
completed, which was followed by the assembly and testing of the entire
receiver front-end, from the feed input to the outputs of the first
magic-Ts.
Revision of dewar bottom plate was completed by R. Taggart this week, and
reviewed/approved by M. Stennes.
New bearing balls for the rotating optical table were received, and
successfully installed in the lower race. Work on the upper bearing race
is in progress at the time of this writing.
Checked cardcage wiring and brassboard assembly wire harnesses for LNA
bias, and made changes as needed. Used K-band amplifier as first test.
After success of K-band LNA bias, went on to bias all four W-band LNAs
successfully. Presently, LED bias wires are being added to the
harnesses. ... M. Stennes
26-40 GHz Receiver:
Work continues on the receiver. Components were rearranged as described last week. One of the A3 amplifiers failed during our tests, and a mixer was found to be defective. An IF amplifier was constructed (adapted by Steve White and Bob Simon from one of Steve's designs), including a LO notch filter, and is being tested in one channel. Randy is working on the phase switch driver transient issue and progress is encouraging. For the first time since this work began, last night the receiver and CCB were reconnected and data was gathered overnight. No results are yet available.
R. Norrod
2 Dec 05
Digital Electronics Status 17 Nov 2005 – 2 Dec 2005
***Operations, Problem summary***
The receiver group has complained about the inability to reset the mcb cards in the receiver room after a power outage. The digital performed some electrical tests in the receiver room on Tuesday and verified the electrical operation of the reset lines. However, tests seemed to indicate that the mcb cards still were not being reset. With some help from the SDD, we found that we were in fact testing incorrectly. (The software now automatically re-initializes cards after a reset.) Re-running the tests per instructions from Ray Creager showed that indeed the mcb cards were being reset. This still leaves us with the problem that the system does not seem to recover well after a power outage. I would suggest that, after the next power outage, representatives from all three groups gather to analyze and solve this problem.
***Development***
Cal-Tech Continuum Backend (CCB):
This week, some progress was made in attenuating switching transients in the data. The circuitry that drives the switches has been redesigned and perfoms much better on the bench. Tests are presently being conducted to determine the efficacy of the modifications on the receiver.
Spare components for the power supply system were ordered. Drawings for the chassis were submitted to the shop.
***Plans***
- Update documentation
- Support commissioning efforts
- work on phase switch transients
Single Dish Development #150 – Friday, December 2, 2005
Today ends Week 2 of 6 in the final development cycle of 2005. Details are available at PlanOfRecordC82005. This week, Tim Robishaw’s new observing procedure was implemented and can now be tested. Similarly, the changes that will reduce configuration latency when minimal keywords are reset are being tested, and will be patched in ASAP.
GBTIDLv1.2 was released on Tuesday and there were already 15 downloads as of Wednesday. Release notes can be reviewed at http://wiki.gb.nrao.edu/bin/view/Data/GbtidlReleaseNotes_1_2 and highlights include enhanced robustness for continuum operations, new commands for convolving and resampling spectra, and proper handling of NaN (“not a number”) entries.
Regarding the infrastructure upgrades, the simulator has been compiled and is running under RHEL4. Compilation problems with CCB on the updated platform are being explored. All control system libraries now compile with gcc3. Porting of the DCR and VME drivers is now beginning.
Preview instructions for the spectral line GFM plugin under development were handed out to the local support scientists this week. They are encouraged to try it out over the next two weeks in offline mode, and provide comments at the next Observing Issues meeting on December 14th. Paul started the first online tests on Thursday, and was able to see integration by integration displays for several beams and polarizations with respect to lags, channels, and frequency. Although small issues were detected, the display refresh rate was promising.
Operational support this week included investigating the cause of the corrupt antenna FITS file at the start of a project; debugging is planned for maintenance time tomorrow. The messageMux fix developed as a result of operational support last week, when the spectrometer could not be restarted, is being patched in during maintenance today.
A bunch more astrid training and/or hand holding this week. After another set this coming weekend and one the following week, all the "main" pulsar observers will be "trained" and have example scheduling blocks to build on.
We had a close call with the RAIDs on spigot2 two days ago where the raid-controlling daemon flipped out. Restarting the system left one RAID in a "bad" state. Luckily Chris, Wolfgang, and I had seen this a couple times before and were able to prevent the other 3 RAIDs from being "bad" (and the complete loss of a single projects data). But this is another reminder that we should eventually (soon?) move spigot2 to RedHat? Enterprise, or at least a v2.6 Linux kernel (where the Firewire support is much better as well). This is scary, though, since in the past, the EDT drivers have only been stable for v2.4 kernels.
MIT/LL 43m Project -- Glen
The last few weeks we've been performing regular spacecraft tracking. All seems fine
on the 43m side. There have been serious problems with temperature stability in the
MIT/LL trailer. Butch, Carl Stone and others have been working the problem.
Right now it appears the hardware is OK. Changing the ducting, fan setting and
temperature settings may fix the problem.
John, Tim and John are making good progress on the remote monitor upgrade.
We've updated the web pages with 3 real time displays:
The intensity display shows the total power variation (counts)
at 680, 780, 880 and 980 MHz. Each has a 1 MHz bandwidth to
avoid RFI.
The VLBA Base Band Converters could also be used for GBT
peaks at low frequencies.
We are still waiting for news on funding for the second year operations.
-- RichardPrestage - 01 Dec 2005
Revision r1.9 - 02 Dec 2005 - 14:16 GMT - RichardLacasse
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