===================================================================== CONT08 Session Notes August, 2008 First session start: August 12, 2008 0:0000 UT End of last session: August 26, 2008 23:5959 UT The CONT08 sessions will be observed in UT days, i.e. in sessions of 0-24 UT. The schedules are written this way following a request from the analysts. UT day observing is needed to make the most accurate combination and comparison of results from other techniques. ===================================================================== Number of 24-hr sessions: 15 Participating stations: Kokee, HartRAO, Medicina, Ny Alesund, Onsala, Svetloe, TIGO, Tsukuba, Westford, Wettzell, Zelenchukskaya Average number of observations per day: 11,440 Total number of campaign observations: 171,594 ===================================================================== Schedules The sources for the schedules are based on the best 80 sources of the good geodetic source catalog, which showed less than 15% of non- detections in the R1 and R4 sessions in the first half of 2008. An extra 3 seconds is added at the start of each scan for correlator synchronization. These extra seconds are not included in the calculation of the scan SNR. SNR Targets: Minimum SNR for all baselines (except with TIGO): X-band (margin 5): 20 S-band (margin 3): 15 Minimum SNR for baselines with TIGO: X-band (margin 5): 15 S-band (margin 3): 12 Zelenchukskaya was tagged along. ===================================================================== Special Instructions Refer to the schedule summary at the end of the file for the overall schedule of sessions. Several session days will be recorded onto 1 or 2 disk modules. One module may be used to record more than one session or session parts. Several session days are grouped together for sharing disks creating the following recording groups. Recording groups for Kk, Mc, Sv, Tc, Ts, Wf, Wz, Zc: C0801 ==> ---+ C0802,C0803 ==> | C0804,C0805 ==> | C0806,C0807 ==> +---> Washington C0808,C0809,C0810 ==> | C0811,C0812 ==> | C0813,C0814,C0815 ==> ---+ Recording groups for Hh, Ny, On: C0801 ==> ---+ C0802,C0803 ==> | C0804,C0805,C0806,C0807 ==> +---> Washington C0808,C0809,C0810 ==> | C0811,C0812,C0813,C0814,C0815 ==> ---+ All CONT08 sessions will be correlated at the Washington Correlator. This includes also the R1-equivalents. CABLE CAL CHECK: A cable check should be performed before the start of the first session and after the end of the last session. Stations should NOT do any cable cal checks (or anything else that might interrupt the 5 MHz to the antenna unit) between sessions. SYSTEM CHECKS: With the exception of C0801, all CONT08 sessions have a two-hour slot for each station to perform system and pointing checks. The two-hours slots for all stations are staggered over the 24-hour period of the session. Stations should check the system and pointing during the two-hour slot preferably during the first 30 min of the slot (to allow for corrective measures in the subsequent 90 min if necessary). The station is scheduled in tag-along mode during the two-hour slot allowing the station to leave and re-enter the session at any given moment of the slot. The slots are as follows (for C0802 through C0815): Weekdays: Hh 12-14 UT Kk 18-20 UT Mc 06-08 UT Ny 10-12 UT On 08-10 UT Sv 04-06 UT Tc 16-18 UT Ts 00-02 UT Wf 14-16 UT Wz 18-20 UT Zc 02-04 UT Weekend: Hh 13-15 UT Kk 00-02 UT Mc 15-17 UT Ny 17-19 UT On 11-13 UT Sv 05-07 UT Tc 21-23 UT Ts 07-09 UT Wf 19-21 UT Wz 07-09 UT Zc 09-11 UT Stations should rejoin as soon as possible. Before rejoining please consider the slewing time from the antenna's current position to the next source. You may need to pick a slightly later source in order to have enough slewing time. Stations with AZEL antennas should also check the cable-wrap of the next source, as shown in the schedule listing. If the wrap needs to change, you may need to pick a later source that will allow the antenna enough time to slew around. If your antenna interface does not respect the cable-wrap parameter in the "source=..." command, you may need to force the antenna to the new wrap manually. FS TIME: Please check your FS/formatter clock offset during each system check period with: sy=run setcl & If the offset has exceeded +/- 25 centiseconds, please reset the FS clock model with: sy=run setcl offset & Please be sure to verify the formatter time against GPS so that you are not just reseting the FS to an incorrect formatter time. MODULE SHIPPING: The modules can be sent as soon as no further recording is planned on them. This can be at the end of a recording group, or within a recording group when a module filled up and the recording is continued on a second module. Stations should label the modules to indicate which session(s) the modules contain. The R-type sessions will be processed within the nominal 15 day time delay for the rapid sessions. These sessions require that the modules be shipped to the correlator by express. The expedited shipment holds also for modules that contain both rapid and non-rapid data. LOG FILES: Log files should be ftp'd to the IVS Data Center every day, following the end of each session. This will ensure the logs are available for the correlator to set up for pre-passing and for processing the rapid sessions. It will also let the status of each station be checked. Automatic scripts process the logs each night, the summary files and plots are posted on the session web page, and the session performance matrix is updated. STARTING SCHEDULES: For the first schedule you will need to make sure that you start it early enough to reach the first source. Please check to make sure you go to the right cable wrap for this scan. If your antenna interface does not support the "cable wrap" parameter for the "source=..." you may need to force the antenna to the right wrap manually. Of course changing the wrap will require more time. The cable wrap needed can be found in the DRUDG listing (for example the one from option 5) or from the "source=..." command in the .snp file. Starting with the second schedule we have allowed enough time to slew to the new source from any antenna position if the schedule is started by 0000 UT. Enough time is included for a change in cable wrap if it is necessary, based on the position of the expected position of the antenna at the end of the previous schedule. The cases where a change in cable wrap is necessary, or there may be a change in direction necessary, are given in the table below. If your antenna interface supports the "cable wrap" parameter for the "source=..." command you can ignore this table. If your antenna does not implement the "cable wrap" parameter, then you may need to manually force a wrap change according to the table. For schedule day transitions with "Y", the antenna is expected to need a wrap change. For schedule day transitions with "m", the antenna may need to be forced to go the long way depending on where it ends the previous schedule. For schedule day transitions with a ".", no action is expected. Please check your schedule listings to help determine what the needed action is in the "Y" and "m" cases. When it is necessary to manually force the direction of antenna motion, please begin the change in wrap as soon as possible after the end of the previous schedule. Cable-wrap changes at schedule day changes. ------------------------------------------- Stations -------------------------------- Days Hh Kk Mc Ny On Sv Tc Ts Wf Wz Zc Old new -------------------------------- 1 2 . m m . m . m . . m . 2 3 . . . . . . . . . . . 3 4 . . . . . m . . . . . 4 5 . . . . . Y . . . Y . 5 6 . . m Y . m m . . m . 6 7 . . . . . Y . . . Y . 7 8 . . . m . . . . . m m 8 9 . . . Y . . . . . Y . 9 10 . . . . . . . . . . . 10 11 . . . . . . . . . . . 11 12 . . . . . m . Y . . . 12 13 . . . . . . . Y . . . 13 14 . . m . m m Y . . m Y 14 15 . . . . . . m . . . . ----------------------------------------- This table gives the expected cable-wrap changes for each station on the changes between schedule days in CONT08. Y = changes wrap m = may need to go long way . = no change expected ----------------------------------------- In order to get as much data, and with as few gaps, as possible, we have allowed a minimum of only 3 minutes for changes between schedules. In other words, at a schedule transition the old schedule will end recording by 23:57:00 UT and the operator needs to start the new schedule before 00:00:00 UT. This is a short time, but we think it should be sufficient. For stations with Mark 5 recorders we think that at most two operator actions should be needed for a schedule transition. The first action is that between some schedules it may be necessary to change the recording bank with a "mk5=bank_set=inc;" command and then wait up to 20 seconds for the recorder to settle for the "Selected" LED to come on. The second is that every schedule transition will require the new schedule to be started with a "schedule=..." command. The "bank_set" command should require less than 30 seconds for the operator to enter and 20 seconds or so for the Mark5 to complete since the module can already be inserted. The "schedule=..." command should require 30 seconds or less to enter. This still leaves an additional minute and a half or so in case an old module must be removed and a new one inserted and selected and/or there are minor problems. In case of a more serious problem, please rejoin the schedule as soon as possible. Since we are not expecting many problems, we didn't want to allow a lot of extra time to handle them, but we recognize that they may happen. Once the schedule has started, you will need to quickly enter a "mk5relink" to continue the schedule after the "halt" in "ready_disk". We aren't as familiar with K5 operations, but the personnel at Tsukuba feels that 3 minutes is sufficent time. It should be possible to automate the transition for Mark 5 stations if there is no need to manually force a cable wrap change or insert a module. You can do this by placing a procedure, perhaps called "change", in the "station" procedure library with contents similar to: "uncomment next two lines if a bank change is needed "mk5=bank_set=inc;" "!+30s schedule=con08nnxx,#1 where "nn" is the schedule number and "xx" is the station's two letter code. Before the schedule change time, the operator would enter a time schedule command such as: change@2008.ddd.23:58:00 were "ddd" is the day number. The contents of "change" would need to be modified for each transition, changing the schedule name and possible commenting/uncommenting the "mk5=..." and "!+30s" commands as appropriate. You will also need to comment out the "halt" in your "ready_disk" procedure. This approach has NOT been tested, but we expect it to work. If you want to use this approach, it can easily be tested before use and/or should be monitored the first time it is used. Other schemes are possible as well. MODULE TESTING: Please test all modules you will use for CONT08, including spares, before the session begins. To do this, please record a few seconds of data, do a "scan_check", and erase the data. There will not be time to test the modules during the session, but we expect failure will be rare. Please monitor the first "scan_check" after a change of module, particularly at schedule transition, to make sure the new module is working. If not, please change to a new module and rejoin the schedule as soon as possible. Please set the bad module aside, inform the Coordinating Center (ivscc@ivscc.gsfc.nasa.gov) and only try to re-use it if you have otherwise run out of media toward the end of CONT08. ===================================================================== Table 1: CONT08 Observing Plan Summary Day Code Start End Correlator Rapid --- ----- ---------- ---------- ---------- ----- Mon system check cable check Tue C0801 225-000000 225-235700 Washington *R1* (system check) Wed C0802 226-000000 226-235700 Washington (system check) Thu C0803 227-000000 227-235700 Washington *R4* (system check) Fri C0804 228-000000 228-235700 Washington (system check) Sat C0805 229-000000 229-235700 Washington (system check) Sun C0806 230-000000 230-235700 Washington (system check) Mon C0807 231-000000 231-235700 Washington *R1* (system check) Tue C0808 232-000000 232-235700 Washington (system check) Wed C0809 233-000000 233-235700 Washington (system check) Thu C0810 234-000000 234-235700 Washington *R4* (system check) Fri C0811 235-000000 235-235700 Washington (system check) Sat C0812 236-000000 236-235700 Washington (system check) Sun C0813 237-000000 237-235700 Washington (system check) Mon C0814 238-000000 238-235700 Washington *R1* (system check) Tue C0815 239-000000 239-235959 Washington Wed cable check Notes for stations: - Do NOT do any cable checks other than the two checks shown. - Each schedule will end no later than the "End" time. - Stations must send modules for the "Rapid" sessions express to the correlator, as usual. The correlator is Washington for all sessions. - Stations should label the disk modules to show which CONT08 session days are recorded. - Stations should confirm all initiated shipments to the correlators. - The observation of the Int1 and Int2 Intensives will continue during CONT08. There will be no Int3 Intensive. The pointing slots of two hour length are aligned with the Int1 and Int2 Intensive observing periods. The stations Kk, Ts, and Wz will leave the CONT08 schedule and re-join it after the Intensive as soon as possible. The re-entry can occur at any time during the two-hour slots, as the stations are added in tag-long mode during that period - When schedule days change, enough time has been allowed to slew from the last source of the old schedule to the first source of the new schedule assuming the new schedule is started by 0000 UT. However for AZEL antennass if the cable-wrap needs to be changed and the antenna interface will not handle this automatically, it will be necessary to manually force the antenna to the correct wrap. The cases where the wrap changes between schedules are listed in the following table. In these cases, at the end of the old schedule and if your antenna will not change wraps automatically, you should promptly take action to force the needed change in the wrap. - If necessary, it should be possible to automate the change in schedules in cases where manual intervention is not needed to change the cable wrap. If you want to do this and want advice, please contact Ed (Ed.Himwich@nasa.gov). Notes for the correlator (WACO): - A disk module may contain data of 1, 2, or possibly 3 observation days. The disk modules have labels according to the sessions being recorded. - A session may be spread over 2 modules for one station and fit on a single module for another station. - The Int1 and Int2 Intensive sessions will be observed during CONT08. There are no Int3 Intensive sessions scheduled. The correlation of the Int1 and Int2 sessions has precedence over CONT08 correlation. - Five of the 15 CONT08 days are considered rapid turn-around sessions. These R1 and R4 equivalents are to be correlated first. The equivalents are: C0801 = R1, C0803 = R4, C0807 = R1, C0810 = R4, C0814 = R1. - The accumulation period (AP) should be set to 3 sec. ===================================================================== Table 2: Recording Groups and Module Usage Summary: =================================================================== Hh Kk Mc Ny On Sv Tc Ts Wf Wz Zc Avg =================================================================== C0801 1267 1594 779 1069 1028 661 2266 982 1373 762 472 1114 ----------------------------------------------------------- B D A B B A G B B A A =================================================================== C0802 1163 1665 775 1039 962 638 2263 867 1393 801 485 1096 C0803 1110 1685 718 1059 1000 639 2152 975 1404 846 502 1099 ----------------------------------------------------------- 2273 3350 1493 2098 1962 1277 4415 1842 2797 1647 987 2195 H H D D,B D B H D G D B =================================================================== C0804 1110 1633 782 1035 960 639 2169 1012 1402 822 479 1095 C0805 1167 1596 744 1054 1034 638 2160 926 1397 896 502 1101 . ---------- . . -------------------------------- . 3229 1526 . . 1277 4329 1938 2799 1718 981 2196 . 2D D . . B H D G D B ======== . ========== . . ================================== C0806 1150 1576 772 1012 1028 658 2105 965 1360 932 521 1098 C0807 1166 1591 761 1004 978 643 2090 941 1370 851 497 1081 ----------------------------------------------------------- 4593 3167 1533 4105 4000 1301 4195 1906 2730 1783 1018 2179 H 2D D H G B H D G D B =================================================================== C0808 1127 1555 786 992 1011 637 2131 952 1377 795 495 1078 C0809 1142 1563 759 999 998 640 2183 901 1363 845 497 1081 C0810 1152 1637 769 1003 1004 630 2080 964 1408 848 521 1092 ----------------------------------------------------------- 3421 4755 2314 2994 3013 1907 6394 2817 4148 2488 1513 3251 H H G H G D H,A G G,A G D =================================================================== C0811 1096 1544 737 1041 1005 636 2054 902 1388 812 519 1067 C0812 1151 1610 748 1025 1029 651 2086 993 1334 901 509 1094 . ---------- . . ---------------------------------- . 3154 1485 . . 1287 4140 1895 2722 1713 1028 2161 . 2D D . . B H D G D B ======== . ========== . . ================================== C0813 1215 1634 786 1061 1047 628 2160 982 1319 927 491 1114 C0814 1254 1591 775 1065 1024 657 2252 978 1369 758 469 1108 C0815 1094 1611 746 1069 1026 627 2065 935 1425 827 514 1085 ----------------------------------------------------------- 5810 4836 2307 5261 5131 1912 6477 2895 4113 2512 1474 3307 H H G H H D H,A G G,A G D =================================================================== Module sizes: A ( 960 GB) B (1440 GB) D (2000 GB) G (4000 GB) H (6000 GB) Notes: - Example (recording group C0808,C0809,C0810 and station TIGO): + record session C0808 on the H module, + record session C0809 on the H module, and + record first part of session C0810 on the H module and the remaining part on the A module. - Suggestions for handling disk module changes are provided at the end of this document. - Tsukuba will record on K5 disks and then e-transfer to Haystack. Haystack records data on listed Mark 5 modules. - Each station has one or two spare modules alloted that shall be used when a regular disk fails: Hh H Kk 2D Mc G Ny H On G Sv D Tc H,A Ts G Wf G Wz G Zc D - An "extra" disk is normally inserted once recording has started on the last allocated disk for an experiment. This is done in case the last allocated disk fills early. Normally this should be the smallest available spare. However, if some other disk used in the experiment has failed and filled prematurely, the station should consider how much additional space is likely to be needed when selecting the "extra" disk. Please inform the coordinating center (ivscc@ivscc.gsfc.nasa.gov) whenever you use a spare. ===================================================================== Recording mode Name Code GEOSX8N 8F Recording mode setup for: HARTRAO KOKEE MEDICINA NYALES20 ONSALA60 SVETLOE TIGOCONC TSUKUB32 WESTFORD WETTZELL ZELENCHK Mode Tot.Rate Tot.BandW #chan #bits Barrel Mk341:1 506.368 Mbits 253.184 MHz 14 2 NONE Chan.BW #Subpasses Tracks(*fan) Tot.tracks Speed 8.00 MHz 1 32(*1) 32 0.02 X-band spanned bw= 720.0 MHz rms spanned bw= 280.4 MHz S-band spanned bw= 140.0 MHz rms spanned bw= 50.9 MHz Effective number of channels recorded per sub-pass X S Total 19.780 11.868 31.648 ===================================================================== =================== DISK MODULE CHANGES =================== These experiments will require 1, 2, or 3 disk modules each. Stations should follow the assigned list of modules according to Table 2 in these notes. DRUDG does not know the sizes, so it shows an ever-increasing GByte count in the listings. Please be aware that you may have to change modules during some schedules, plan accordingly. Here are four suggestions for handling the changes: 1) Mark module change times. Select the modules you will use for each experiment, note their sizes, and then mark by hand the approximate places in the schedule where each module is expected to be full (you will have to estimate this when you start an experiment with a partially filled module). This is the time when you should expect to change a module. Mark by hand which bank will be changed and which module will be inserted. You can use the DRUDG Option 5 listing for this purpose. 2) Change modules promptly. When a module is full, the FS will automatically switch to the next one and put up a prompt window saying that you should change the old one. It is good practice to change the module as soon as it's called for because then the FS will have a module to switch to in case the one being recorded to becomes full prematurely. You should check periodically during the experiments that the modules are filling at the expected rate. The window prompting you to change the module will give both the VSN and bank that needs to be changed. You should dismiss the window once the module has been changed. 3) Label the modules before removing then from the Mark 5, also affix a red dot. This will help avoid mixing-up the modules. At a minimum, label the module with the experiment it was used in and its sequence number. You should be able to print a label using: cd /usr2/log drudg LOG_NAME VSN where LOG_NAME is the name of the experiment log, including the ".log" and VSN is the eight character VSN. This can be done even when the FS is still writing to log during the experiment. It should be done whenever a module has been filled or a schedule has ended (in the case of a not completely filled module). This ensures that the label contains the correct complete information. The label should then be affixed promptly to help keep track of the module contents. 4) When inserting or removing a module, turn the latch to "locked" or "unlocked" only when the Mark 5 is not recording. In addition, do not turn the key to "locked" unless the FS will be not be sending commands (either to setup or start recording) to the Mark 5 for at least 20 more seconds. An "unlocked" module can be safely slide in or out at anytime. If you have any questions, please contact Ed Himwich (Ed.Himwich@nasa.gov).