RV150 (Astrometric/Geodetic VLBA-150) 2021 NOV 24 18:00 UTC DOY 328 Notes prepared by David Gordon (USNO) (david.gordon126.civ@mail.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. RV150 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 1803+784 21328-180000| 348 300 300 300 300 376 300 356 376 310 351 300 300 300 315 | 2127-096 21328-180635| 300 309 351 365 365 | 0642+449 21328-180718| 334 358 472 488 343 416 488| 0642+449 21329-172716| 322 328 328 300 313 300 326 328 333 333| 2127-096 21329-172933| 300 304 300 309 309 | 2229+695 21329-173603| 320 324 336 322 323 327 300 338 321 320 322 338 327 338 | 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 10% and the average scan time increases from 109 seconds to 134 seconds. The observing time increases most at the faster antennas and least at the slower antennas. Purpose ======= This is the sixth of six coordinated astrometric/geodetic sessions in 2021 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: rv150.skd At the IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2021/rv150): Sked file: rv150.skd Text file: rv150.txt At the VLBA/NRAO: Sked file: rv150.skd Vex file: rv150.vex Text file: rv150.txt Summary file: rv150.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: 59 60 47 59 61 61 56 60 69 70 69 60 60 58 55 66 64 61 % cal. time: 5 6 3 5 6 5 5 5 4 4 4 5 6 5 4 4 3 5 % slew time: 28 27 46 27 27 27 25 27 18 2 20 27 27 27 32 10 10 24 % idle time: 7 6 4 8 6 6 13 7 8 24 7 7 6 8 8 19 22 10 total # scans: 463 480 252 452 491 474 420 452 371 304 330 471 482 451 341 371 277 404 # scans/hour : 19 20 11 19 20 20 18 19 15 13 14 20 20 19 14 15 12 17 Avg scan (sec): 111 108 160 113 107 111 115 115 161 198 180 110 108 112 138 153 199 134 # 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): 3.28 3.31 2.59 3.27 3.35 3.35 3.09 3.34 3.81 3.85 3.80 3.30 3.34 3.23 3.01 3.63 3.52 3.36 # OF OBSERVATIONS BY BASELINE | Br Fd Hh Hn Kp La Mk Nl Ny Ns On Ov Pt Sc Sh Wz Yg Total ----------------------------------------------------------------------------------------------- Br| 345 3 285 360 360 264 331 131 105 76 384 361 235 58 65 9 3372 Fd| 7 304 432 444 243 372 93 77 63 371 455 316 37 62 7 3628 Hh| 13 5 7 0 9 40 27 65 1 5 17 109 85 192 585 Hn| 288 309 158 358 144 110 100 266 304 354 38 113 1 3145 Kp| 432 280 351 96 72 58 418 449 284 49 58 10 3642 La| 248 383 97 81 62 385 462 301 39 62 7 3679 Mk| 203 77 54 30 296 254 143 103 27 45 2425 Nl| 121 95 76 322 375 326 37 80 5 3444 Ny| 232 174 100 96 106 116 176 37 1836 Ns| 167 78 80 90 79 131 27 1505 On| 57 63 99 92 260 54 1496 Ov| 395 236 55 57 10 3431 Pt| 300 42 61 9 3711 Sc| 21 118 0 2946 Sh| 105 141 1121 Wz| 58 1518 Yg| 612 Number of 2-station scans: 474 Number of 3-station scans: 215 Number of 4-station scans: 112 Number of 5-station scans: 90 Number of 6-station scans: 71 Number of 7-station scans: 94 Number of 8-station scans: 58 Number of 9-station scans: 79 Number of 10-station scans: 115 Number of 11-station scans: 24 Number of 12-station scans: 20 Number of 13-station scans: 18 Number of 14-station scans: 11 Number of 15-station scans: 6 Total number of scans: 1387 Total number of obs: 21048 INTENSIVE BREAKS ================ WETTZELL will drop out from ~18:15-19:45 on DOY 328 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 77 sources in this session: 61 are from the geodetic source list and 16 are weak sources being re-observed or observed for the first time at S/X bands. 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.