GBT Operations & Commissioning Meeting
AGENDA
-
- The grout repair under joint 31 cured well, and the telescope was released for normal operations Friday afternoon. A thermistor embedded in the grout appears to track air temperature closer than earlier thought. This would be good news in that differential expansion between the steel track and the concrete foundation may be less than earlier thought, but this is only one measurement point.
- No word yet on NSF approvals of our major contracts. Stay tuned.
- We are putting together more information this week in our litigation effort with Lockheed-Martin.
-
- New air handling unit controllers, chiller package supervisory controls, and a universal network controller have all been installed on the GBT for the HVAC controls upgrade. Development of screens and software inputs are also complete enough for control. We need to add thermocouples to the water lines, and replace one failed chilled water valve, and the GBT portion of the project will be complete and ready for fine tuning. Work will now move up to the Jansky Lab.
We supported 16 projects in 24 observing sessions. Average setup times was 19 minutes -- I still can't find any patterns in what class of projects require more setup time. The telescope was also scheduled for 17 hrs of maintenance, 7 hrs of program and receiver checkouts, and 2 hrs of software tests.
Lost time amounted to 11.7 hrs, about 7.8% of the time scheduled for tests and observing. High winds cost us about half of this. The breakdown of lost time is:
- Winds : 5.1 hrs
- Various Astrid problems : 3.2 hrs
- BCPM/Astrid : 0.8 hrs
- Remote Observer didn't 'show up' : 0.7 hrs
- Scan Coordinator FITS files : 0.5 hrs
- PF wouldn't 'balance' : 0.5 hrs
- User script error : 0.4 hrs
- All others (Spectrometer, Active Surface) : 0.5 hrs
The frequency of Astrid problems seems to have gone down in the latter parts of the week. Almost all other problems were single incidences.
Last Week
=========
Observations for proposals
GBT06A-051, GBT06A-042, GBT06A-066,
GBT05C-020, GBT05B-032, GBT05B-023,
GBT05B-034, GBT06A-003, GBT05C-045,
GBT06A-027, GBT06A-049, GBT06A-028,
GBT05C-029, GBT06A-060
Completed proposals
GBT05B-023, GBT05C-029, GBT06A-060
Next Week
=========
Observations scheduled for **
GBT06A-051 [F ] Marcel Agueros
Detecting Pulsar Companions to Very Low-Mass
White Dwarfs
GBT06A-030 [F ] Don Campbell
Lunar surface studies via S-Band radar imagery
and interferometry
GBT06A-053 [F ] Scott Ransom
Continued Timing of the Binary and Millisecond
Pulsars in Terzan 5
GBT06A-042 [ P ] Raghvendra Sahai
A Mysterious Outflow Source --- Protostar, Dying
Star, or Something Else ?
GBT06A-054 [ B] Paul Demorest
Long-term Precision Timing of Millisecond Pulsars
GBT05C-041 [F ] Marcel Agueros
Detecting Pulsar Companions to Two Very Low-Mass
White Dwarfs
GBT05B-042 [ B] Michael Kramer
Timing and General Relativity in the Double
Pulsar System
GBT06A-066 [ B] David Nidever
HI Mapping of the Extended Magellanic Stream
GBT05C-042 [F ] Scott Ransom
Timing the Binary and Millisecond Pulsars in
NGC6440 and NGC6441
GBT05C-020 [ P ] Tony Remijan
Confirmation Of Interstellar Methyltriacetylene
(CH3C6H) Toward Tmc-1
GBT05C-032 [ P ] Yancy Shirley
Tracing Protostellar Mass During Star Formation
with 7mm and 9mm Continuum
GBT05C-065 [ P ] Jim Braatz
Measuring the Extragalactic Distance Scale: A
Target of Opportunity
GBT06A-014 [ P ] Andrea Tarchi
H2O vs Continuum in the Megamaser 3C403:
Reverberation Mapping of the Nucleus
GBT05C-023 [ B] Fernando Camilo
PSR J1833-1034, the Very Young Pulsar in the SNR
G21.5-0.9
GM062 [F ] M. Orienti
What causes the very broad HI absorption in radio
galaxies?
GBT06A-049 [ P ] Tony Readhead
Definitive Detection of Excess Arcminute Scale
CMB Anisotropies
GBT06A-027 [F B] Karen Masters
Mapping Matter in the Nearby Universe with 2MASS
GBT06A-038 [F B] Tom Troland
Magnetic Fields in the Galactic Halo via the HI
Zeeman Effect
GBT06A-018 [ P ] Joe McMullin
Isotopic Abundances in Planetary Nebulae
** Scheduled as F-ixed, P-rimary, B-ackup
Contact Information for 03/16/2006 - 03/30/2006
=======================================
Proposal PI Bands Email [NRAO contact]
---------- ------------------ ----- --------------------
GBT06A-040 Mark McKinnon LK mmckinno@nrao.edu [Toney Minter]
GBT06A-053 Scott Ransom S sransom@nrao.edu [Scott Ransom]
GBT05A-020 Yancy Shirley K yshirley@as.arizona.edu [Frank Ghigo]
GBT06A-032 Jim Braatz Q jbraatz@nrao.edu [Jim Braatz]
GBT06A-011 Mike Blanton L blanton@nyu.edu [Karen O'Neil]
GBT06A-066 David Nidever L dnidever@virginia.edu [Jay Lockman]
GBT05A-033 Ingrid Stairs L istairs@astro.ubc.ca [Scott Ransom]
GBT06A-046 Glen Langston U glangsto@nrao.edu [Glen Langston]
GBT05C-065 Jim Braatz K jbraatz@nrao.edu [Jim Braatz]
GBT04C-031 Paul Kondratko K pkondrat@cfa.harvard.edu [Jim Braatz]
GBT06A-068 Yancy Shirley K yshirley@as.arizona.edu [Toney Minter]
BB217 Edward Boyce C eboyce@nrao.edu []
GBT06A-049 Tony Readhead B acr@astro.caltech.edu [Brian Mason]
GBT06A-038 Tom Troland L troland@pa.uky.edu [Jay Lockman]
GBT06A-027 Karen Masters L kmasters@cfa.harvard.edu [Karen O'Neil]
BB184 Jim Braatz K jbraatz@nrao.edu []
GBT05C-026 Tom Devlin XQ devlin@physics.rutgers.edu [Brian Mason]
GBT06A-018 Joe McMullin Q jmcmulli@nrao.edu [Dana Balser]
GBT04A-038 Brian Mason B bmason@nrao.edu [Brian Mason]
GBT06A-009 Jim Condon K jcondon@nrao.edu [Jim Braatz]
BH139 David Hough X dhough@trinity.edu []
GBT06A-050 Steve Begin S sbegin@physics.ubc.ca [Scott Ransom]
Scheduled hours [backup]
========================
Category/Month-> March April May
Astronomy ~ 625 [375] 541 [492] 477 [326]
Maintenance ~ 20 [068] 16 [102] 20 [068]
Test & Comm ~ 98 [036] 148 [046] 144 [039]
Un-assigned ~ 2 17 103
Proposal Checkouts
==================
Awaiting checkout - 0
Active checkout - 0
On Hold - 22
Schedule - 67
Completed - 458
Current backlog [hours prior to 06A*] = 1045
[2001:2(1), 2002:88(2), 2003:19(1), 2004:161(11), 2005:647(32), 2006:128(3)]
Total time to discharge [hours] = 2933
* Includes projects that are on hold for trimester 06A
Operations
Stennes followed up on an investigation into the failure of 1PPS/5MHz? in the VLBA DAR. Found and corrected several likely causes (with Nathan Sharp) (all local to the DAR). Installed a voltage transient monitor on a suspect power supply.
Investigated reported problem with PF1 800 MHz observing. Discovered
setup problem that incorrectly set LO frequency.
Nothing else of note.
Development
Ka RX, Zpectrometer:
Components for redesigned phase switch driver electronics are in house,
circuit board design is progressing. Couplers are plated and in house,
will be tested early next week. Long lead MW components for zp taps are on order. Working with Jeff Cromer to try to nail down the electronics rack requirements.
Lab Spectrometer IF System:
Filter designs are out for fabrication. Some electronic components are
on order. Physical layout is in progress in Inventor.
Converter Module Power Sampler Upgrade:
Electronic components ordered last week are in house. Circuit board
design should start next week.
C-Band Receiver:
RF/IF Assembly interface specification was accepted as written, at this
week's project meeting. Presently, Stennes is requesting and receiving
budgetary quotes for all required components, and is continuing trade-off
studies for a few proposed configurations (electrical and mechanical). Beginning to look at thermal design issues for new cryostat.
3mm Receiver:
Machine shop is nearing completion of waveguide dewar feedthroughs, and
vacuum fittings. T. Guthrie is working through some Autodesk Inventor
tutorials, in hopes that he can later generate a 3-D mechanical model of
the 3mm RFE. Receiver block diagram was modified and archived, reflecting
the addition of Zpectrometer taps.
LO Reference Distribution System:
Working with Don Campbell, generated a specification for a frequency
standard for radar experiments at S-band. Part of thinking on how to live with the 28Hz maser sidebands.
Penn Array Rx:
99.995% pure helium ordered and received. A plan devised for evacuating lines and replacing contaminated He.
ORM Power Divider:
Tests of the power divider without all the amplifiers installed were very close to the predicted results. Based on the results amplifiers were specified for the underpowered ones in the Converter_Filter modules. Looks as if an $166 spectrum microwave amplifier will increase the compression point from +18 to +24 as needed.
Q-band:
Test dewar assembly drawing 95% complete. Only minor modifications are
required before submission to the shop. Drawing for test dewar cart should be submitted to shop next week.
MLLN 140 Project:
IF converter boards returned, parts ordered. The shop has just begun fab of housing for the splitter and the PLL circuits.
2Mar06 - Norrod, Anderson, Simon, Stennes, Watts, White
Digital Electronics Status 23 Feb. 2006 – 2 Mar., 2006
***Operations, Problem summary***
The active surface problem was fixed last Friday. In earlier attempts to fix it, we managed to destroy the configuration of one-eighth of the system. With a little help from an “old guy” at the factory, we managed to figure out how to reconfigure the system. A procedure detailing how to do this was written and put in a few safe places.
***Development***
This week, group’s efforts were divided amongst ALMA projects, Active Surface RFI shielding, 140-ft restoration, mentoring, transfer of responsibilities, and RFI mitigation.
Cal-Tech Continuum Backend (CCB):
No progress.
Test Spectrometer
No progress.
***Plans***
- Continue CCB construction.
- Continue LTA troubleshooting.
This ends Week 2 of 6 in the second development cycle of 2006 which can be viewed at PlanOfRecordC22006.
The MR for fixing stop and abort for pulsar observations was successfully sponsor tested and patched into v6.1. We are currently working on two additional MRs for Observation Management: (1) We are adding a new Observing Directive which will allow pulsar observers to change the target data directory at any time in a Scheduling Block, and (2) We are removing the behavior of using the previously set scan duration within a Scan Type all non-Auto* Scan Types. These are MRs generated from past Observing Issues meetings.
Two antenna MRs are ready for sponsor testing. The first MR is an enhancement to the antenna FITS file which will allow the LFCs to be recorded in the FITS file primary header. The second MR deals with a bug fix for the Antenna FITS file columns, OBSC_AZ & OBSC_EL.
We are currently coordinating with UMd on creating a M&C Manager for the Zpectrometer.
We placed the monitor and control code created for the CCB by CalTech under our revision control system.
Penn Array development is currently stuck. We upgraded to the latest IRC release. Because of IRC architecture changes, we had to modify the GBT FITS archiver to work with the new version of IRC. This work has been slow because there are no release notes available for IRC. We are currently testing the new version of IRC with the archiver changes. The new version of IRC appears to have issues with resource management (memory leaks) and to be less reliable than the previous version. We are coordinating with Goddard and UPenn to solve these issues.
Operational support for this week was light.
We did not hold a meeting this week.
Several support-related issues with the Astrid+BCPM observations that occurred this week. Most of the problems have been ironed out, but there is another session today, so we'll see.
Mark completed the MR for the spigot data-directory changing directive for astrid which I signed. This is the last major addition (we think) that astrid needs for spigot observations.
MIT/LL 43m Project -- John and Glen
- The PLC, RTAI Servo/M&C systems, and CITECT operator interface systems are all working.
- A pointing test was done last week, and was successful.
- The hydraulic sensors are all installed, but programming of the PLC and CITECT is not yet complete. Expect this to continue next week and the following week due to personnel absences.
- MIT/LL disk packs installed. Total storage is now 18 Tera-bytes.
- Feed/Receiver calibration continuues to give somewhat perplexing values. Noise figure for LNA and all electronics from Front End to trailer is 0.99 dB, excluding feed contribution. They plan on bringing a new first stage LNA package with deware in June.
- We will start tracking next.
- All funding for FY 2006 is released. We will write a statement of work for FY 2007 and FY 2008. They already have funding through April 2007, and will be writing a proposal for additional years of operation.
-- RichardPrestage - 02 Mar 2006
Revision r1.11 - 03 Mar 2006 - 14:27 GMT - GlenLangston
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