RV151 (Astrometric/Geodetic VLBA-151) 2022 JAN 19 18:00 UTC DOY 019 Notes prepared by David Gordon (USNO) (david.gordon4@navy.mil, david.gordon126.civ@us.navy.mil) Special notes for this session: =============================== This session will use the RDBE/DDC/Mark6 system at the VLBA sites, as in previous RV sessions. The X-band frequencies are: 8365.75, 8445.75, 8805.75 and 8925.75 MHz, and spans 560 MHz. The S-band frequencies have are: 2212.75, 2242.75, 2282.75 and 2372.75 MHz. HOBART26 is still down for repairs and is being replaced by YARRA12M. The ending in .75 MHz is necessary at the VLBA stations. Therefore it will not be possible to monitor phase cals using the 10 kHz filters. RV151 will record 8 16-MHz bandwidth channels using 2-bit sampling. The bit rate will be 512 Mbits/sec. The data will be correlated at the VLBA using the VLBA DiFX software correlator. There are 7 non-VLBA stations scheduled - HARTRAO, NYALE13S, NYALES20, ONSALA60, SESHAN25, WETTZELL and YARRA12M. The non-VLBA stations should see the "Special operations notes for non-VLBA stations" section below for special instructions. To facilitate fringe-finding, there are some long scans on fairly strong sources with many antennas near the beginning and end of the schedule. All stations please try to be onsource and recording data for these scans. These scans are: Source Start DURATIONS name yyddd-hhmmss Br Fd Hh Hn Kp La Mk Nl Ny Ns On Ov Pt Sc Sh Wz Yg 0016+731 22019-180000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 | 2325+093 22019-180629| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 | 1519-273 22019-181315| 300 300 300 300 300 300 300 300| 1803+784 22020-174538| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 | 2325+093 22020-175237| 300 300 300 300 300 300 | 1519-273 22020-175326| 300 300 300 300 300 300 300| We are again using the 'Fill' scheduling option. 'Fill' is run after a schedule is finished in the normal manner. It increases the scan times at stations, when possible, based on how much idle time each station has before its next scan. We used a 'FILL_OFF' margin of 5 seconds. Using 'Fill' on the original schedule, the average observing time increases from 49% to 61%, the average idle time decreases from 22% to 11% and the average scan time increases from 110 seconds to 129 seconds. The observing time increases most at the faster antennas and least at the slower antennas. Purpose ======= This is the first of six coordinated astrometric/geodetic sessions in 2022 that use the full 10-station VLBA plus several geodetic stations capable of recording VLBA modes. This year's series is a continuation of the highly successful RDV series begun in 1997. These are now being run under the USNO's VLBA time allocation. These sessions are being coordinated by the geodetic/astrometric VLBI programs of USNO, NASA and NRAO. They have been designed so that the same data set may be used by each agency for its particular goals. Schedule information ==================== This is a new schedule generated by David Gordon at USNO using sked. Schedule file name: rv151.skd At the IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2022/rv151): Sked file: rv151.skd Text file: rv151.txt At the VLBA/NRAO: Sked file: rv151.skd Vex file: rv151.vex Text file: rv151.txt Summary file: rv151.sksum This session uses the VLBA stations and 7 IVS stations. The IVS stations are: HARTRAO, NYALES20, NYALE13S, ONSALA60, SESHAN25, WETTZELL and YARRA12M. Below is the sked summary. Key: Br=BR-VLBA Fd=FD-VLBA Hh=HARTRAO Hn=HN-VLBA Kp=KP-VLBA La=LA-VLBA Mk=MK-VLBA Nl=NL-VLBA Ny=NYALES20 Ns=NYALE13S On=ONSALA60 Ov=OV-VLBA Pt=PIETOWN Sc=SC-VLBA Sh=SESHAN25 Wz=WETTZELL Yg=YARRA12M Br Fd Hh Hn Kp La Mk Nl Ny Ns On Ov Pt Sc Sh Wz Yg Avg % obs. time: 60 64 43 59 64 64 57 62 65 64 65 63 64 59 51 65 61 61 % cal. time: 5 5 3 5 5 5 5 5 4 3 4 5 5 5 4 4 4 5 % slew time: 25 25 47 25 25 25 25 26 19 2 21 25 25 25 32 10 11 24 % idle time: 9 5 6 11 5 5 12 6 11 29 9 6 5 10 12 20 23 11 total # scans: 420 446 272 414 449 443 411 427 376 299 354 434 440 421 355 370 312 390 # scans/hour : 18 19 11 17 19 18 17 18 16 12 15 18 18 18 15 15 13 16 Avg scan (sec): 123 123 137 122 122 125 121 126 149 186 159 125 126 121 124 151 168 135 # data tracks: 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 # Mk5 tracks: 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 Total TB(M5): 3.31 3.52 2.38 3.24 3.51 3.54 3.17 3.43 3.58 3.56 3.61 3.47 3.55 3.25 2.83 3.58 3.36 3.35 # OF OBSERVATIONS BY BASELINE | Br Fd Hh Hn Kp La Mk Nl Ny Ns On Ov Pt Sc Sh Wz Yg Total ----------------------------------------------------------------------------------------------- Br| 299 7 256 317 315 257 292 118 98 58 333 312 210 67 57 11 3007 Fd| 8 284 409 410 232 345 88 75 59 348 413 294 37 53 12 3366 Hh| 15 5 7 0 12 48 19 75 5 7 27 111 102 199 647 Hn| 266 282 153 338 120 97 95 235 277 323 36 81 1 2859 Kp| 415 254 330 87 71 48 383 419 267 44 47 16 3378 La| 237 353 93 74 54 363 432 279 37 52 11 3414 Mk| 190 66 52 26 287 243 146 102 24 58 2327 Nl| 104 92 74 294 344 309 36 68 3 3184 Ny| 212 182 85 92 89 116 177 32 1709 Ns| 160 68 73 70 80 121 21 1383 On| 42 54 82 73 269 50 1401 Ov| 367 225 50 38 18 3141 Pt| 274 39 52 14 3412 Sc| 21 73 0 2689 Sh| 97 168 1114 Wz| 62 1373 Yg| 676 Number of 2-station scans: 535 Number of 3-station scans: 226 Number of 4-station scans: 119 Number of 5-station scans: 76 Number of 6-station scans: 71 Number of 7-station scans: 74 Number of 8-station scans: 72 Number of 9-station scans: 58 Number of 10-station scans: 106 Number of 11-station scans: 26 Number of 12-station scans: 14 Number of 13-station scans: 24 Number of 14-station scans: 9 Number of 15-station scans: 3 Number of 16-station scans: 0 Number of 17-station scans: 0 Total number of scans: 1413 Total number of obs: 19540 INTENSIVE BREAKS ================ WETTZELL will drop out from ~18:15-19:45 on DOY 019 to observe the one-hour UT1 Intensive session. And there may also be a USNO/VLBA Intensive at about the same time, in which case HN-VLBA and MK-VLBA and maybe more stations will drop out for ~1.5 hours. SOURCE SELECTION ================ There are a total of 73 sources in this session: 60 are from the geodetic source list and 13 are weak sources being re-observed to reduce their position uncertainty. SCHEDULING ALGORITHMS ===================== This schedule uses the "SRCEVN SQRT" mode of Sked. In the absence of any constraints, Sked will preferentially observe strong sources that have high visibility. This mode attempts to smooth out the number of observations per source. RECORDING MODE and FREQUENCIES ============================== The data will be recorded using the following setup: 8 channels, each 16 Mhz bandwidth 1:2 fan-out 32 MHz sample rate 2-bit sampling This recording mode is a modified version of 512-16(RDV). S-band frequencies were modified for the RFI situation at HOBART26. There is no correlator speed-up factor. The frequency sequence covers 560 MHz at X-band and 160 MHz at S-band using 4 channels in each band. At the VLBA, the X-band uses two LO's in order to fit into the VLBA 512 MHz passband. At the Mark4 stations, the X-band uses both the high and low parts of the geodetic receivers. Because only 8 channels are available when observing with the VLBA/RDBE/DDC systems, a wider spanned bandwidth is not advisable. The following tables list the setup for the VLBA stations and the geodetic stations with DBBC, Mark IV, Mark 5, and VLBA5 back ends. VLBA | HARTRAO Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 8080.0 A1 285.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 8080.0 A1 365.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 8080.0 B2 725.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 8080.0 B2 845.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 2020.0 C1 192.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 2020.0 C1 222.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 2020.0 C1 262.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 2020.0 C1 352.75 14 VLBA | YARRA12M Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 7600.0 A1 765.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 7600.0 A1 845.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 7600.0 B4 1205.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 7600.0 B4 1325.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 1900.0 C2 312.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 1900.0 C2 342.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 1900.0 D2 382.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 1900.0 D2 472.75 14 VLBA | ONSALA60, WETTZELL Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 8080.0 A1 285.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 8080.0 A1 365.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 8080.0 B1 725.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 8080.0 B1 845.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 2020.0 C1 192.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 2020.0 C1 222.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 2020.0 D1 262.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 2020.0 D1 352.75 14 VLBA | NYALES20 Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 8080.0 A1 285.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 8080.0 A1 365.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 8080.0 B1 725.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 8080.0 B1 845.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 2020.0 C1 192.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 2020.0 C1 222.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 2020.0 C1 262.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 2020.0 C1 352.75 14 VLBA | NYALES13S Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 8080.0 A1 285.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 8080.0 A1 365.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 8080.0 B1 725.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 8080.0 B1 845.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 1700.0 C1 512.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 1700.0 C1 542.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 1700.0 D1 582.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 1700.0 D1 672.75 14 VLBA | SESHAN25 Chan Sky Tracks LO IF BBC | LO IF BBC BBC# 1 X 8365.75 2, 4, 6, 8 7600 B 765.75| 8100.0 A 265.75 3 2 X 8445.75 10,12,14,16 7600 B 845.75| 8100.0 A 345.75 4 3 X 8805.75 18,20,22,24 9600 D 794.25| 8100.0 B 705.75 5 4 X 8925.75 26,28,30,32 9600 D 674.25| 8100.0 B 825.75 6 5 S 2212.75 3, 5, 7, 9 3100 A 887.25| 2000.0 C 212.75 9 6 S 2242.75 11,13,15,17 3100 A 857.25| 2000.0 C 242.75 10 7 S 2282.75 19,21,23,25 3100 A 817.25| 2000.0 D 282.75 13 8 S 2372.75 27,29,31,33 3100 A 727.25| 2000.0 D 372.75 14 Special operations for non-VLBA stations: ========================================= All non-VLBA stations: Please note that due to the frequency sequence, phase-cal will not be visible with a 10 kHz viewing filter in the USB channels. If you have another means to verify phase-cal, please use it. If you have a Mark IV Decoder, please contact Ed.Himwich@nasa.gov if you would like advice on how to set it up to check phase-cal for this frequency sequence. Please check the procedures created by drudg. The discussion below represents our best understanding of the station configuration. If you find an error, please correct it and let us know so we can correct the catalog. HARTRAO: This station uses a DBBC rack. BBCs 3 & 4 are used at X-band with IF A, input 1. BBCs 5 & 6 are used at X-band with IF B, input 2. BBCs 9, 10, 13 & 14 are used for S-band with IF C, input 1. WETTZELL: This station uses a DBBC rack. BBCs 3 & 4 are used at X-band with IF A, input 1. BBCs 5 & 6 are used at X-band with IF B, input 1. BBCs 9 & 10 are used for S-band with IF C, input 1. BBCs 13 & 14 are used for S-band with IF D, input 1. ONSALA60: This station uses a DBBC rack. BBCs 3 & 4 are used at X-band with IF A, input 1. BBCs 5 & 6 are used at X-band with IF B, input 1. BBCs 9 & 10 are used for S-band with IF C, input 1. BBCs 13 & 14 are used at S-band with IF D, input 1. NYALES13: This station uses a DBBC rack. BBCs 3 & 4 are used at X-band with IF A, input 1. BBCs 5 & 6 are used at X-band with IF B, input 1. BBCs 9 & 10 are used for S-band with IF C, input 1. BBCs 13 & 14 are used at S-band with IF D, input 1. SESHAN25 The logs from SESHAN25 indicate that the station uses a VLBA5 rack, but we are not sure that is correct, please let us know. BBCs 3 & 4 are used at X-band with IF A, input NOR. BBCs 5 & 6 are used at X-band with IF B, input NOR. BBCs 9 & 10 are used for S-band with IF C, input NOR. BBCs 13 & 14 are used at S-band with IF D, input NOR. For Mark IV racks, the IF3 command in the procedure IFDSX assumes that VC3 and VC10 will be patched to High. Please verify that the switches for your IF3 module are wired this way, and if they are not please edit the IF3 command to change the switches. The standard wiring is described in "help=if3". If you have questions about the wiring, please contact Brian Corey at Haystack. If you wish to record back-up channels, please add appropriate instances of bbcxx=..., vcxx=..., valo=..., va=..., vblo=.., and/or vb=... commands to the BBC/VC setup procedure. CHECKLIST for non-VLBA stations =============================== Please follow the checklist below to ensure you have done all the necessary steps for this session: 1. Make .prc file with DRUDG and check them out, or use the procedures from the last RV session. Check out parity check procedures. 2. Make the .snp file with DRUDG. 3. Set up your system to monitor the clocks with the "gps-fmout" or "fmout-gps" commands. If you have questions about this, please contact Ed Himwich as soon as possible. 4. Send a "ready" message an hour or so before the session to the ivs-ops mail list (ivs-ops@lists.nasa.gov). Copy analysts@nrao.edu and vlbiobs@nrao.edu on your ready message. 5. Send a "start" message soon after you have started recording. Copy analysts@nrao.edu and vlbiobs@nrao.edu on the message. 6. At the end of the session, send a "finish" message summarizing how the session was conducted. Copy analysts@nrao.edu and vlbiobs@nrao.edu on your message. 7. Transfer your log file to your normal IVS data center. The directories for the IVS servers are listed below: ftp ivsopar.obspm.fr/ivsincoming ftp ivs.bkg.bund.de/ivsincoming Correlation =========== This session will be correlated at the NRAO/VLBA on the VLBA DiFX software correlator. The VLBA correlator can now only read Mark6 modules. The non-VLBA stations will need to E-transfer their data to Haystack, where it will be copied onto a Mark6 module and shipped to the VLBA in Socorro, New Mexico. These stations will need to coordinate this with Haystack Observatory (contact: Jason SooHoo at jsoohoo@haystack.mit.edu). The VLBA needs to process this session as soon as possible because of limited media. So please try to set up the E-transfer as soon as possible after the session ends.