Summary of the 3mm GMVA Session May, 8-13, 2008 ------------------------------------------------ This session was sucessfull, all stations particpated. Pico Veleta was affected by bad weather, which allowed only limited recording. EB, PdB, Metsa recorded all time. PdB recorded with new 3mm receivers in dual polarisation. Onsala started later due to a receiver problem, which was fixed on May 10. At the VLBA the weather was ok in the beginning, but towards the end of the experiment degraded. An ftp fringe check performed during the 1st observing hour on May 9 revealed fringes between the stations which participated in this: EB, PV, PdB. Here are some more details: --------------------------- Effelsberg: no major problems, very good weather, clear sky and no clouds throughout the whole session. During daytime sun heating caused some problems with pointing and focus. Typical Tsys ~ 130-150 K at zenith, tau=0.08 during night, 0.012-0.15 during day time. An undetected non-recording due to a broken 8pack led to the loss of ~1-2 hrs of data. An azimuth encoder jump caused ~2 hours of wrong pointing during the last part of 1803+78 (May 13). Pico Veleta: Poor weather, many scans lost. A number of good observing hours expected for BLLAC, 0716+714, 1803+784. Almost no data for: MRK501/3C345, NRAO150, 3C84, 3C111. PdBure: Particpated under good conditions, towards the end of the exp. the weather degraded May 8: weather calm, Tsys 95 K (LCP), 85 K (RCP) May 9: weather calm, during day time sun avoidance of NRAO150, local project May 10: weather calm, during day time sun avoidance of 3C84, local project May 11/12: weather calm morning thick fog, snowfall May 13: continue observing but some heavy clouds in the last hours Metsahovi: May 9: good weather, no problems reported May 11: good weather, no problems reported Onsala: May 8: receiver problems, expect delayed start May 10: receiver fixed, start 06:45 UTC, Tsys ~ 250-300 K observed until the end without major interruption VLBA: VLBA did not observe continuously, because of scheduled gaps on: May 10, 01h30-04h00 UT & 05-12 UT and May 11, 05-13 UT. At these times local projects were observed. Inspection of the site weather on the internet gave following results: May 9: NL,PT overcast other stations: good May 10: BR scattered clouds NL clouds other stations clear May 11: NL, FD thick clouds, rain at NL BR cloudy other stations clear May 12: NL, FD clouds LA, PT, BR rain KP, OV, MK clear This is the VLBA log: VERY LONG BASELINE ARRAY OBSERVING LOG -------------------------------------- Project: C081A Observer: Krichbaum, T. Project type: VLBI Obs filename: c081acrd.* Date/Day: 2008MAY08/129 Ants Scheduled: NL FD LA PT KP OV BR MK =UT-Time===Comment===============================================MF#===%AD==AMD= Operator is Heidi Gerhardt GPS delta, UT1-UTC (-0.41), vclock ok WEA: LA windy and chance of rain %LA 3mm receiver has a bad cal, Tsys values will be 22676 elevated but data is ok. NL false ellipsoid flagging of data 2357 Begin (part A) 0000 Date is 2008MAY09/130. 0025-0103 *KP mk5 comm lost TAPE 100 38 0053-1927 %PT getting intermittent HC2 FIFO errors. This is 21522 happening multiple times per hour. Errors are clearable. Site tech was consulted, but there's nothing to be done about it at the moment. Most likely this is not actually affecting data. 0108 %PT 35+ mph wind caution 0112-1927 *BR 3mm cycling a little CRYO 5 342 0153 %MK 35+ mph wind caution 0545 Operator is A. Sowinski. 0738-0740 *BR FRM position error. FRM 100 2 0754-0830 *KP Mark5 unit has gone offline, I am unable to 22675 100 36 connect to it. I will try toggling the power by remote control. This should take about 30 minutes. 0846 %MK 35+ mph wind gusts. 1005-1005 %PT Mark5 recording glitch. 1221-1256 *KP Mark5 offline again, see above. 22675 100 35 1222-1226 *LA FRM position error. FRM 100 4 1237-1240 *BR FRM position error. FRM 100 3 1244 FD reports wea: scattered stratus clouds, dry. 1350 New operator is Betty Ragan. 1400 PT reports partly cloudy weather, calm and dry. BR reports clear skies, some dew on the dish. 1514 OV reports clear, dry weather. 1529 LA reports weather: dry and overcast. 1723-1727 %OV HC2 FIFO errors. They appear to have cleared by themselves. 1820 KP reports scattered high thin clouds. 1904 %MK high wind gusts. 2015-2016 *KP MK5 offlined itself for some reason. REC 100 1 It came right back up when I gave it an online command. 2031-2032 *FD stopped recording while site tech swapped TAPE 100 1 out the disc. 2100-2101 *PT not recording during disc swap. TAPE 100 1 2156 New operator is Heidi Gerhardt 2247-2252 *OV not recording during disc swap TAPE 100 5 0000 Date is 2008MAY10/131. 0011-0025 *KP mk5 lost comm 22675 100 14 0030-0040 *KP offline checking reconnection of chatterbox TAPE 100 10 !!!!!!!!!!!! 0114-0333 *Not observing, VLBA running another project !!!!!!!!!!!! 0343 OV 35+ mph wind caution 0451-0452 LA comm down still observing !!!!!!!!!!!! 0452-1201 *Not observing, VLBA running another project !!!!!!!!!!!! 1205 Antennas on source. 1209-1235 *KP mark5 offline and unable to communicate. 22675 Will have to cycle power on mark5 unit. New Operator: Paul Padilla 1455-1539 *KP Mk5 lost comm. Had to use chatterbox to 22675 100 44 reset power. Took a couple of tries to do it properly. 1604 *KP doComent error claiming Mk5 not recording for 30 seconds. 1607-1609 *LA Rotation drive fault FRM 100 2 1638-1640 *KP FIFO errors on HC2 FMTR 100 2 1744 New operator is Betty Ragan. 1915 %MK high winds. 2129-2201 *KP mark 5 went down again. Power cycling it 22675 100 32 via the chatterbox. 2143 OV reports clear, dry weather. 0000 Date is 2008MAY11/132 0146 %NL raining. 0150 New Operator is Alan Kerr 0207-0209 *NL FRM Rotation error. FRM 100 2 0210 LA continues on dial backup. 0337-0342 *LA FRM rotation error. FRM 100 5 0337-0342 *BR FRM rotation error. FRM 100 5 0411 %BR precipitation starting. 0421 BR precipitation stopped. 0439-0453 *KP Mark5 is OFFLINE. Using Chatterbox to 22675 100 14 power cycle the Mark5. !!!!!!!!!!!! 0453-1315 *Not Observing. VLBA running another project at this time. !!!!!!!!!!!! 1315 Begin C081AC except MK which starts at 1711. 1315 %NL precipitation continues. 1338 New Operator: Paul Padilla 1711 MK begins 1711-1745 *MK not in file due to incorrect observe file sent HUERR 100 34 1741-1744 *OV temporarily out while Site Tech switched REC 100 3 packs 1822-1825 *LA rotation position error FRM 100 3 1828-1829 *KP Formatter errors on HC2 FMTR 100 1 1922-1923 *KP Rotation motion analysis fault. FRM 100 1 2043 New operator is Betty Ragan. 0000 Date is 2008MAY12/133. 0150 New Operator is Alan Kerr 0410-0412 *KP FIFO on HC2. FRM 100 2 1345 New Operator: Paul Padilla 1449-1451 *PT autostowed in power glitch. COM 100 2 1625-1628 %KP site tech doing maintenance on communications OTHER Mk5 may be out temporarily. 1727 %PT windy 1924-1925 *KP FIFO on HC2 2200 New operator: T. Perreault 2201 OV 55+ mph wind stow warning 2217-2231 *OV not recording on Mark5. Site tech wanted REC 100 14 to switch to partially used pack in bank A (MPI-0508) in order to put a second partially used pack in bank B to get through the night. When I switched over, the Mark5 went into RECORDING STATE CHANGING OFTEN (switching between MOUNTED / RECORDING / IDLE states). Called site tech, he will pull the modules and reboot the Mark5. 2357-2359 *FD subreflector FOCUS BRAKE fault. Cleared. FRM 100 2 0000 Date is 2008MAY13/134. 0137-0141 *LA subreflector out of position in ROTATION FRM 100 4 commanded to position. 0314 MK commercial power glitch has resulted in temporary building and antenna UPS alarms. 0549 Operator is A. Sowinski. 0940-0941 *KP Formatter errors on HC2. FMTR 100 1 1256 FD reports wea: scattered stratus, dry. 1341 New Operator: Paul Padilla 1645 %OV windy 1737-1927 %FD focus off by around 0.2. Simply commanding FRM it into position isn't working, but the error is small, so data is still good 1927 End. Downtime Summary: Total downtime : 665 min Percentage downtime of observing: 1.2% Average downtime per hour : 0.7 min Total scheduled observing time (# Antennas): 55440 min (8) Notes: * = Entries where data was affected. % = Entries where data may have been affected. & = Entries where the site tech was called out. WEA = Weather entries. MF# = Maintenance form or major downtime category associated with a problem. %AD = The percentage of an antenna affected by a problem. AMD = Total antenna-minutes downtime for a problem. Tsys = System Temperature (TP/SP x Tcal/2) ACU = Antenna Control Unit FRM = Focus/Rotation Mount RFI = Radio Frequency Interference VME = Site control computer CB = Circuit Breaker vclock = Program that compares site clock time to a standard.