SSOC Tohban Report for Week 13 (March 29 - April 4) 1993 S. Tsuneta, K. Koyama, R. Kano Rev. B: additions after WOM 1. Solar Activity Solar activity was generally low. 2. SSOC Operations OG Upload 02 April, Pass1 (930402-0823) Two new OGs were uplaoded (#54 CYEND STBY and #79 CYEND REC) for NIXT special operation. 3. SXT Table Write Date(passs number) & Table Name 30 March, Pass4 (930330-1238) & 930330 T1 P4 NEW SXT CAL 31 March, Pass2 (930331-0929) & 930331 T1 P2 ARS1 LONG EXP 01 April, Pass2 (930401-0930) & 930401 T1 P2 NIXT TEST SEQ 01 April, Pass4 (930401-1136) & 930401 T2 P4 ARS1 LONG EXP 02 April, Pass1 (930402-0823) & 930402 T1 P2 NIXT TEST 2 02 April, Pass3 (930402-1030) & 930402 T2 P3 ARS1 LONG EXP 4. STT Timer Set 29 March, Pass2 (930329-1031) STT tracking was confirmed to be OK. Next update should be done on 5 April. 5. BCS Calibration 31 March, Pass2 (930331-0929) & BSC STIM CAL 31 March 1858-1911(UT) & BSC Souce CAL 6. NIXT OP/SXT table for NIXT Simulation We simulated the NIXT operation between Pass1 (930402-0823) and Pass4 (930402-1134) on 2 April. The test was successful. The OP sequence and SXT table for the NIXT collaboration are now frozen. The only uncertainty is DSN cancellations for the shuttle support. 7. Errors 7.1. SXT Error 31 March, Pass5 (930331-1239) SXTE-J STATUS READ error indicates that SXTE-U was not responding to SXTE-J commanding (hang-up). SXT was recovered by 'SXT Recovery Plan' in the same pass. 7.2. BSC Error 01 April, Pass2 (930401-0930) BCS was recovered in the next pass. 8. Problems/open issues 8.1. SSOC procedure There are some discrepancies between the actual SSOC works (and its timing) and the manual instructions especially in the DSN management area. We will try to update the manuals today. 8.2. SSOC laser printer Flare1 printer sometimes does not work well. We had a difficulty in printing a DSN deletion pass list with Pike's program. 8.3. Communication with JPL It is not clear which format should be used for deletion requests of DSN preliminary and final schedules. We used the same format (the format with many columns) for all types of deletion requests to JPL. JPL will discuss this format issue on their Monday. There are other trivial but important problems. All the open issues are summarized here: a. Terminology used here (FINAL, Preilimnary, Strawman) may not be consistent with those used at JPL. Is Prelimnary sometimes called Update? b. Should we make acknowledgement to JPL for what kind of information or update they provided? c. Is FAX info no longer sent to us except STRAWMAN schedule? d. Should we make major deletions based on STRAWMAN or UPDATE? If we optimize DSN based on STRAWMAN, FINAL will not be optimized due to further deletions from JPL side. If we delete on FINAL, taht would impact scheduling on JPL side. e. Which format specified by JPL is used for which itypes of deletions is unclear. f. Manual instruction of DSN operations here at SSOC is totally out of date, and needs to be updated to reflect the current style. These specific problems are pending Jim Lemen's arrival. He will negotiate with JPL. 8.4. DSN playback time misalignment (reported by Kosugi) There were two cases that BDR playback continues after DSN LOS: DOY 72 (March 13) 1106 UT Canberra 73 (March 14) 1128 UT Canberra Kosugi and Hudson found that manaul relocation of the BDR playback to later time in OP to avoid the collision of BDR mode transition from REC to PLAYBACK done and BDR PAUSE was the cause. This case happens only in the night DSN playback. Antenna change should have been done earlier keeping the start time of the PLAYBACK in the same place. A few algorithm changes of OP-FIRST-GUESS are necessary. This will be done by Jim Lemen. See 'On the Data loas at DSN' by Kosugi and Hudson for details. 9. Hikitsugi 9.1. Main frame #2 Note that Saturday is a holiday. Mainframe#2 did not start automatically on last Saturday. We had to start it manually. 9.2. FAX from JPL JPL will stop sending us DSN schedules by FAX. 9.3. STRAWMAN DSN schedule In addition to FINAL and PRELIMNARY schedules, a STRAWMAN schedule for + 3 week came from JPL last week. JPL asked us to send them the deletion information for the +3 week. we did not delete any DSN contact listed in the STRAWMAN schedule. Some of the DSN passes are located between KSC first and second passes. It is, however, left as is, because it is not clear which 5 orbits among 6 KSC orbits are chosen for contacts. 9.4. Pike's program There is a wonderful program called Pike's program to list DSN deletions with JPL format using RASM data. This is not in the manual. But, do the following: idl> cancel_prelim, weeknumber 9.5. STT STT eclipse timer should be updated on 5 April. 9.6. NIXT collaboration OP and SXT table for NIXT were frozen. OP for April 8 (which will be uplaoded on April 7) was already prepared by Shimizu san. Please be careful NOT TO DELETE THE OP. JPL however, warned us further deletions for April 8 trackings due to the shuttle operation. Two DSN passes following the NIXT collaboration where we are supposed to dump the data are in the RASM FINAL list as of last Saturday. JPL, however, has not yet guaranteed these two passes following NIXT. SSOC toban should moniter the DSN FINAL schedule with RASM every day. Depending on the DSN deletions, the OP needs to be updated. (There are already other deletions for May 8, so that the update needs to be done anyway.) We (Kano, Tsuneta) will support the SSOC toban for NIXT operation on April 8.