SSOC Tohban Report for Week 43 (21 Oct. - 27 Oct. 1996) SSOC: T. Yokoyama and G. Slater KSC : T. Yoshida and T. Shinkawa Meeting Attendance: Y. Ogawara, H. Hudson, L. Acton, T. Yokoyama, T. Watanabe, T. Kosugi, A. Sterling, S. Savy, Sawa, H. Hara, S. Yashiro, G. Slater T. Shimizu 0. Action Items: Week-35-A/I-1 /Ogawara, Hara/ status: TABLED An action item to investiage the cause of recurrent problems with of the S-3500 at KSC has been tabled because no problems have occurred for several weeks. The investigation will continue if and when further problems recur. Week-42-A/I-1 /Yoshida/ status: OPEN T. Yoshida has produced preliminary software to aid in optimizing the Yohkoh DP rate in OPs. The final implementaion of Yoshida san's software will probably have to await the next visit by Jim Lemen Week-43A/I-1 /Slater, Watanabe, Seko/ status: OPEN After discussions with Watanabe san and Seko san, G. Slater will respond to the concerns of DSN regarding the number of Yohkoh retransmission requests (see item 4.7 below). 1. Solar Activity: Solar activity remained low during week 43. The GOES low energy channel hovered around the A1 level all week. The large remnant of the long lived active region transited the disk over the course of the week. 2. Standard Operation: 2.1 SXT Table Uploads: ------------------------------------------------------------ Pass ID Pass # Table ID ------------------------------------------------------------ Mon 961021-1444 5 961022 P5 ARS1 DKCAL Tue 961022-1548 4 961022 P4 ARS1 DKCAL Thu 961024-0001 4 961024 P4 ARS1 LONG Sat 961025-1547 4 961025 P4 ARS1 LONG ------------------------------------------------------------ 2.2 STT timer setting The STT timer was set during on 21 Oct during the second pass. The STT timer was shutdown on 26 Oct during the second pass. 2.3 Spacecraft offset pointings: A 3 arc minute offpoint to the west was executed during pass 1 on 25 Oct (18:00 UT). The purpose of the offpoint is to watch the limb passage of the decaying active region. The offset was maintained through Sunday and will probably be increased to 5 arc min on Monday. 3. Errors and Problems 3.1 No BCS Errors 3.2 No SXT Errors 4. DSN Communications: 4.1 DSN Final schedule for W43 (last week): 6 passes cancelled. 4.2 DSN Final schedule for W44 (this week): 3 passes cancelled. 4.3 DSN Preliminary schedule for W45: No passes cancelled. 4.4 DSN Strawman schedule for W46: 28 passes cancelled. 4.5 Data Transmission from DSN: (Status: See /home/flare1/yohkoh/dsn_corrupt/96_XX) 276 76 0048 not received Requested 15 Oct. not received tape Requested 18 Oct. not received Requested 22 Oct. Closed/ give up 276 76 1959 not received Requested 15 Oct. not received tape Requested 18 Oct. not received Requested 22 Oct. Closed/ give up 276 16 0222 2% less than expected Requested 15 Oct. 2% less than expected tape Requested 18 Oct. Closed/ correct data 276 16 0404 8% less than expected Requested 15 Oct. 8% less than expected tape Requested 18 Oct. Closed/ correct data 278 16 0117 2% less than expected Requested 11 Oct. Closed /correct data 278 16 0259 4% less than expected Requested 11 Oct. Closed / correct data 279 16 0136 5% less than expected Requested 18 Oct. Closed / correct data 282 17 2324 18% corrupted Requested 15 Oct. no responce Requested 18 Oct. 283 17 2200 not received Requested 16 Oct. not received Requested 22 Oct. Closed / correct data 283 17 2345 4% less than expected Requested 16 Oct. no response Requested 22 Oct Closed / correct data 284 16 2036 not received Requested 16 Oct. not received Requested 22 Oct. Closed / correct data 288 76 1653 not received Requested 17 Oct. Closed/correct data 289 76 1856 not received Requested 17 Oct. Closed/ correct data 292 76 1301 not received Requested 23 Oct. 293 17 2000 5% less than expected Requested 25 Oct. 4.6 On Friday, 25 October, Seko san reported that data from a Canberra pass on DOY 252 was recovered. The data had been mistakenly assumed to be ASCA data. The pass had been closed out and final reformatting has already been done, but the data will remain on th Sirius data base, if it is needed in the future. 4.7 DSN Concern Over High Frequency of Yohkoh Retransmission Requests Jose Valencia of DSN sent an e-mail message to Yohkoh operations expressing his concern over the overburdening of the 'CDR' by the high number of 'retransmission' requests from Yohkoh and ASCA. (see accompanying copy of his message at end of report). 5. Yohkoh/ASCA/AKEBONO Pass Conflicts at KSC: Week 43: 5 passes given to ASCA. Week 44: 4 passes given to ASCA. 6. Special Activities: None. 7. Holiday Schedule: The next KSC holiday is Sunday, 3-Nov-1996 JST. 8. Hikitsugi Items: 8.1 Tohbans for W44 SSOC: T. Watanabe and S. Yashiro KSC: T. Shinkawa and Y. Nishino 8.2 STT Timer setting The next setting is due on 2 November (Saturday). 8.3 Sirius Data Nothing to report. 8.4 OP_first_guess Recall the warning from the previous reports: op_first_guess fails to switch the KSC LOS quiet high (QT HI) to the medium (QT ME) mode of OP plan in the next day operation when KSC pass2 is cancelled. Tohbans should pay attention to this when checking the OP and change it manually. New Bug report (Week 39, Shimojo) The op_first_guess fails to include SXT CAMP OBS in quiet medium for SAA zone. Tohbans should change the rate mode or delete SXT CAMP OBS operations. 8.5 Email terminator information to SXT CO The SXT chief observer prefers to receive any terminator schedule by E-mail (sxt_co@isass0) rather than by FAX. See the note in the SXT CO report. Date: 23 Oct 1996 15:34:21 -0700 From: Jose Valencia To: "seko@flare20.solar.isas.ac.jp" Gentlemen, Because of heavy real-time loading at the supporting stations and increasing support demands at the CDR there is a growing concern with the high number of ASTD and SOLA data retransmission request. FYI, The Comm Chief or the supporting non-DSN station routinely conducts the playback from the CDR or Digital tape as soon as possible following the real-time support with no indications of data transmission problems, however, a retransmission of this same data is later requested!!. To assist us in investigating what we perceive as a problem we have the following questions?. 1. What is the main reason for requesting retransmissions ??. 2. Is the data bad??. 3. What does bad data mean??. 4. Is the transmission interrupted??. 5. What is a nominal block count for ASTD and SOLA. Any information you can provide us that will contribute to the reduction of data retransmissions is welcomed. Our objective is to delivery a satisfactory percentage of data to you on the initial transmission. Thank you for your cooperation. Regards, Jose Valencia Questions for Yohkoh/DSN data handlers (Seko et al) regarding Yohkoh data recovery policy: 1. How long does Seko-san wait for a given DSN downlink to appear on the DSN scheduled transmission list before she requests a 're-transmission', or more accurately, a transmission? Is this wait interval well-defined and adhered to? How was this interval decided upon? Is it in line with that used by other DSN users? 2. Is there a well-defined percentage of missing/corrupt data for a given transmission below which we regard the transmission as successful and do not request a re-transmission? If so, what is that value, how was it chosen, and is it in line with the value used by other DSN users (such as ASCA)?