SSOC Tohban Report for Week 15 (03-Apr-2000 to 09-Apr-2000) SSOC: K. Akita, M. Sawa KSC: S. Kawashima, R. Kano 0. Meeting Attendees H. Hudson, J. Khan, T. Kosugi, T. Sakao, M. Sawa, T. Watanabe Y. Ogawara, S. Watari ------------------------------------------------------------------------------- 1. Solar Activity The solar activity has been milder this week. GOES X-ray background level was gradually decreasing to C1 level. A couple of M1 class flares and a several C-class flares occurred. ------------------------------------------------------------------------------- 2. Standard Operations 2.1 SXT Table Uploads The following SXT tables were uploaded: ====================================================================== JST Day UT Start Time Pass Table ID ====================================================================== Monday 02-Apr-00 19:12 1 000402 P1 ARS2 VLA+JOP83 Tuesday 04-Mar-00 00:28 4 000403 P4 ARS2 JOP83+DK* Wednesday 04-Mar-00 19:31 1 000404 P1 ARS2 JOP83+DF* Wednesday 05-Mar-00 00:38 4 000404 P4 ARS2 JOP83* Thursday 05-Mar-00 21:24 3 000405 P3 ARS2 JOP83* Friday 06-Mar-00 23:16 4 000406 P4 ARS2 JOP83* Saturday 07-Mar-00 21:44 4 000407 P4 ARS2 VLA+JOP83* Sunday 08-Mar-00 18:30 2 000408 P2 ARS1 STD* ====================================================================== 2.2 STT Timer setting STT timer was re-set and started during Pass 2, 000403-1343, on 04-Apr-2000 (JST). The next timer setting should be done on 11-Apr-2000 (Tuesday). ------------------------------------------------------------------------------- 3. Special Operations 3.1 Support of VLA Observations and of JOP083 Has just begun this week, after successfully completing MM6. Special SXT tables were uploaded for this purpose( see 2.1 ). 3.2 BCS-A HV Level Chnage and BCS SRC CAL High voltage power supply for BCS-A was increased by 20V (1 step) in order to boost the detector gain, which had been decreasing significantly. The first trial in pass 2 on Apr. 6 (000405-1340), was not successful due to the mistake in planning the commands. The second trial was done in pass 2 nextday (000406-1340), after changing two OG commands, 97 and 98(dec). Following these operations, BCS SRC CAL was done by OP during a couple of satellite nights in between KSC contatcs. BCS SRC CAL was repeated nextday as the BCS error (see 4.1) might have ruined the CAL data. 3.3 HXT CAL HXT CAL was done in the night times during the KSC contacts; pass1 on Apr. 8(000407-1134), and passes 1 and 2 on Apr. 9(000408-1134 and 000408-1238). ------------------------------------------------------------------------------- 4. Errors and Problems 4.1 BCS Errors: BCS memory checksum error occurred in pass 2 on Apr. 7 (000406-1340). It was successfully recovered in the next available pass (000406-1547). 4.2 SXT Errors: Bit map errors occurred in pass 1 on Apr. 4(000403-1239) and in pass 1 on Apr. 8(000407-1134). They were recovered successfully by Yobi-C commands during the same passes. ------------------------------------------------------------------------------- 5. NASA Station Scheduling 5.1 Contact pass cancellations/additions The following schedule changes were requested: =========================================================================== DSN/NASA Schedule Week Schedule Changes =========================================================================== Real-time 15 0 Cancellation Final 16 0 Cancellations Preliminary 17 0 Cancellation Strawman 18 74 Cancellations =========================================================================== 5.2 Data Transmission from NASA Ground Stations ----(Copy from /home/flare1/yohkoh/dsn_corrupt/2000/00_15)---- 092 76 1248 corrupted tape requested 04-Apr Closed/ same data(13327 blocks) ------------------------------------------------------------------------------- 6. KSC Pass Conflicts and Schedule In Week 15, we lost 9 KSC contacts: 6 to ASCA, 2 to Halca, 1 to Akebono In Week 16, we will lose 10 KSC contacts: 5 to ASCA, 5 to Halca ------------------------------------------------------------------------------- 7. Hikitsugi Items 7.1 Tohbans for next Week SSOC: H.Hudson, S. Watari KSC: R. Kano, K. Fujiki 7.2 STT Timer Setting The next STT TIMER SET is due on Wednesday, 12-Apr-2000 (JST). 7.3 OP OP and command sheets for 11-Apr-2000 should be prepared and transferred to KSC by new SSOC tohbans. Please hurry. 7.4 Holiday Schedule Next Yohkoh holiday will be Sunday, 16-Apr-00 (UT). 7.5 Meeting for long-term scheduling among Halca, Asca, and Yohkoh Will be held in May. 7.6 34m Antenna test at KSC Will be done during Apr. 18-20. KSC AOS/LOS and Antenna-change command sequences should be set in the OPs for all the KSC passes cancelled due to conflitcs. The further details are to be determined in week 16. 7.7 ASCA safehold ASCA fell into safehold mode at 1:35 on Apr. 7 (JST). In oreder to recover it ASAP, they want to use the cancelled KSC passes due to conflicts. On Apr. 10, that would delay AOS time a little bit in pass 1 (000410-1031). What to do on Apr.11 is TBD. ------------------------------------------------------------------------------ 8. Unchanged Hikitsugi Items from Previous Weeks: 8.1 Elevation angle limit at Santiago (w49) Seko_san noticed two fault reports from Santiago (DSS-74) due to low elevation at the end of the pass: These were shown as max elevations of 11.1 degrees (323/1322) and 10.7 degrees (315/1645) in our database. Accordingly, after consultation with Watanabe-san, we suggest increasing the threshold (for this station only) to 13.5 degrees maximum elevation. SSOC Tohban for w09 asked Hudson-san to prepare an azimuth-elevation map in Santiago station. 8.2 Weekend Terminators If possible, please schedule terminator opportunities on any weekend table (i.e., if room permits). 8.3 Keeping Santiago contacts Currently, ASCA conflicts cause the loss of about 10 KSC contacts per week. We do not know which contacts Yohkoh will lose until the weekly meeting. Santiago contacts occur on the same orbits as KSC contacts. Therefore, please keep as many Santiago contacts as possible in the DSN Strawman and Preliminary Forecasts. 8.4 Software Problems pr_gev with /hc keyword produces a temporary output file but does not print it at the printer. 8.5 OP_FIRST_GUESS problem (1999-w38) In a situation with two KSC cancellations on each of two days (a rare condition) the BDR optimization feature of OP_FIRST_GUESS crashed. After experimentation, we found that it ran OK without the final cancellation request (two the first day, but just the first one on the second day). The second one then had to be removed manually. Records of the problem were forwarded to Lemen-san, but no answer had arrived at the time of writing. 8.6 Keeping Wallops contacts (1999-w42) This is not a new policy, but to emphasize (paraphrased from e-mail from Hugh Hudson): We should keep all valid Wallops passes, independent of day/night status, in order to maximize our Wallops use and minimize our DSN use. NASA won't give us many DSN passes anyway, so if we select a Goldstone pass in preference to a Wallops one, we'll normally just lose both. Another reason is that CANCEL_DSN software needs some repair, since it seems to replace the DSS identifier WGS with 0. This is likely to cause confusion, but of course if we don't cancel Wallops passes we won't have this problem often. 8.7 A New Antenna System in Wallops (1999-w43) Since October 1, a new antenna GN-WGS is used instead of a 9m antenna DSS-76 in Wallops station. SSOC tohbans should not be surprised at the unfamiliar antenna code GN-WGS in the DSN schedules. This new code GN-WGS is replaced with DSS-80 in solass.w## and solsf.w## by the program "fmt_wallops". But some programs for the strawman scheduling replace it with DSS-0. 8.8 OP_FIRST_GUESS Problem (1999-w46) During the preparation of 991109-1238 OP,991110-1135 OP and 991111-1032 OP OP_FIRST_GUESS crashed with the message "OP_START_END: problem with detection of LOS/AOS/DSN Repro events". This problem was solved by changing OP_FIRST_GUESS options: choose optimization 1 rather than 2. All these 3 problems above (item 8.10, 8.11 and 8.12) occurred also on week 45 in 1999. 8.9 DSN Pass Additions Yohkoh loses DSN passes as follows: 1) Canceled due to conflicts with ASCA 2) Canceled because Santiago is unavailable 3) Canceled by the SSOC tohbans 4) Deleted by DSN The tohbans should compare the STRAWMAN, PRELIMINARY and FINAL schedules for each week to see if some of the passes lost by case (4) could be replaced by ones from case (3). This means it may be possible to request pass additions for the PRELIMINARY and FINAL week schedules from the (case (3)) STRAWMAN cancellations. The routine to use is ADD_DSN: e.g., IDL> add_dsn, 49 Decide on the complete list of passes to be added and select them like cancel_dsn. Then ftp and email the appropriate file. 8.10 New Orbital Elements The arrival date of new orbital elements at SIRIUS was changed from Wednesday to Tuesday. === END ===