RV156 (Astrometric/Geodetic VLBA-156) 2022 NOV 28 13:30 UTC DOY 332 Notes prepared by David Gordon (USNO) (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 are: 2212.75, 2242.75, 2282.75 and 2372.75 MHz. 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. RV156 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, HOBART26, NYALE13S, NYALES20, ONSALA60, WETTZELL and YARRA12M. These 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 Wz Ho Yg 1803+784 22332-133000| 306 300 328 300 300 318 317 340 340 300 302 300 331 328 | 1749+096 22332-133644| 309 356 360 480 480 480 337 480 | 0648-165 22332-133750| 326 300 304 302 322 317 302 300 326| 0716+714 22333-125918| 300 320 240 315 319 275 377 300 377 312 310 318 325 345 | 0648-165 22333-130608| 313 314 313 313 300 312 313 329 329| 1749+096 22333-130616| 300 327 300 327 300 300 319 | 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 45% to 59%, the average idle time decreases from 25% to 11% and the average scan time increases from 90 seconds to 109 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 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. Schedule information ==================== This is a new schedule generated by David Gordon at USNO using sked. Schedule file name: rv156.skd. At the IVS Data Center (https://cddis.nasa.gov/archive/vlbi/ivsdata/aux/2022/rv156/ Sked file: rv156.skd Text file: rv156.txt At the VLBA/NRAO: Sked file: rv156.skd Vex file: rv156.vex Text file: rv156.txt Summary file: rv156.sksum This session uses the VLBA stations and 7 IVS stations. The IVS stations are: HARTRAO, HOBART26, NYALES20, NYALE13S, ONSALA60, WETTZELL and YARRA12M. Below is the sked summary. Key: Br=BR-VLBA Fd=FD-VLBA Hh=HARTRAO Hn=HN-VLBA Ho=HOBART26 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 Wz=WETTZELL Yg=YARRA12M Br Fd Hh Hn Ho Kp La Mk Nl Ny Ns On Ov Pt Sc Wz Yg Avg % obs. time: 61 61 42 59 50 60 61 58 59 64 63 65 61 61 57 65 63 59 % cal. time: 5 6 3 5 3 6 6 5 6 5 4 5 6 6 5 5 3 5 % slew time: 26 27 50 28 40 27 27 25 27 21 3 23 26 26 26 11 10 25 % idle time: 7 6 5 7 6 6 6 12 8 9 29 6 7 6 11 18 23 11 total # scans: 468 495 255 471 285 492 497 393 486 413 351 392 476 498 452 395 277 417 # scans/hour : 20 21 11 20 12 21 21 16 20 17 15 16 20 21 19 16 12 17 Avg scan (sec): 112 106 141 108 151 106 106 128 105 135 155 144 110 106 109 143 196 126 # 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): 3.35 3.35 2.30 3.26 2.75 3.33 3.36 3.22 0.00 3.56 3.49 3.60 3.35 3.39 3.14 3.61 3.47 3.09 # OF OBSERVATIONS BY BASELINE | Br Fd Hh Hn Ho Kp La Mk Nl Ny Ns On Ov Pt Sc Wz Yg Total ----------------------------------------------------------------------------------------------- Br| 355 3 289 36 375 376 270 338 175 144 80 390 381 244 71 17 3544 Fd| 13 328 32 443 470 254 404 122 103 67 399 470 334 64 11 3869 Hh| 25 171 5 10 0 16 32 21 75 0 7 26 98 190 692 Hn| 3 299 329 155 392 173 150 132 280 321 380 145 0 3401 Ho| 40 31 94 17 25 7 18 49 34 5 31 252 845 Kp| 455 283 379 119 98 63 438 469 293 56 17 3832 La| 256 414 129 110 70 410 484 325 65 10 3944 Mk| 203 105 79 44 303 265 152 31 74 2568 Nl| 146 122 92 350 406 370 96 5 3750 Ny| 278 269 125 127 121 239 29 2214 Ns| 249 101 104 106 205 13 1890 On| 62 68 120 332 40 1781 Ov| 421 258 53 22 3661 Pt| 316 62 14 3949 Sc| 131 0 3181 Wz| 51 1730 Yg| 745 Number of 2-station scans: 2 Number of 3-station scans: 432 Number of 4-station scans: 172 Number of 5-station scans: 83 Number of 6-station scans: 65 Number of 7-station scans: 79 Number of 8-station scans: 84 Number of 9-station scans: 98 Number of 10-station scans: 104 Number of 11-station scans: 44 Number of 12-station scans: 20 Number of 13-station scans: 16 Number of 14-station scans: 16 Number of 15-station scans: 0 Number of 16-station scans: 0 Number of 17-station scans: 0 Total number of scans: 1215 Total number of obs: 22798 INTENSIVE BREAKS ================ WETTZELL will drop out from ~18:15-19:45 on DOY 322 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 VLBA stations will drop out for ~1.5 hours. SOURCE SELECTION ================ There are a total of 74 sources in this session: 60 are from the geodetic source list and 14 are weaker sources being observed for the first time at S/X band. 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 in Australia. 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. 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.