PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 1999-04-30 NOTE = "MGS RST Instrument Health Report HEA9120A.TXT" END_OBJECT = TEXT END Errata ====== Joe Twicken reports an error in the calculation of Allan Deviation included in yesterday's report (HEA9119A.TXT). For details, see below under "Open Loop Data - Analysis". Miscellaney =========== Trish Priest has tallied the number of occultation measurements attempted as of a couple days ago and arrived at 1518. Some were lost for various reasons, and quality varied; so this is only a zero-order estimate of science return. Under the original mission plan, a year of nominal Mapping could have captured as many as 4860 occultations. Engineering Data ================ Engineering Data Statistical Summary from CSV2STAT: First SCET: 1999-04-28T00:00:00.197 Last SCET: 1999-04-28T23:51:44.687 CHANNL CHANNEL TITLE DN-LO DN-HI EU-LO EU-HI EU-AVG/STDEV RECDS ------ ------------- ----- ----- --------- --------- ---------/-------- ----- F-0190 HGA_AZ_ANG 2968 2968 7.25E-01 7.25E-01 7.25E-01/4.83E-09 1246 F-0195 HGA_EL_ANG -6434 -6434 -1.57E+00 -1.57E+00 -1.57E+00/8.86E-09 1246 L-0034 MOT1_RANGING 0 0 14878 L-0036 MOT1_TLM_MOD 0 0 14877 L-0037 MOT1_USO_ENA 0 0 14878 L-0044 MOT2_RANGING 1 1 14878 L-0046 MOT2_TLM_MOD 1 1 14877 L-0047 MOT2_USO_ENA 1 1 14878 L-0053 RF_SW_OSC 2 2 14877 L-0060 TWTA1_FILMNT 0 0 14878 L-0061 TWTA1_HV 0 0 14877 L-0070 TWTA2_FILMNT 1 1 14877 L-0071 TWTA2_HV 0 0 14878 L-0080 USO_PWR 0 0 14878 L-0090 KaBLE_STAT 0 1 14878 L-0091 KaBLE_ENABLE 0 0 14877 L-0111 MOT1_RCV_AGC 255 255 -1.53E+02 -1.53E+02 -1.53E+02/5.93E-07 7791 L-0121 MOT2_RCV_AGC 133 255 -1.53E+02 -1.16E+02 -1.25E+02/8.50E-02 7791 L-0131 TWTA1_HLX_I 0 1 -3.84E-02 -1.85E-02 -3.83E-02/1.39E-05 7791 L-0132 TWTA1_ANOD_V 0 1 -1.00E+03 -1.00E+03 -1.00E+03/2.97E-03 7175 L-0141 TWTA2_HLX_I 38 42 7.05E-01 7.85E-01 7.55E-01/1.42E-04 7791 L-0142 TWTA2_ANOD_V 61 65 -8.66E+02 -8.58E+02 -8.62E+02/1.47E-02 7175 L-0200 USO_REG_V 203 205 4.06E+00 4.10E+00 4.08E+00/7.93E-05 7174 L-0201 USO_OVEN_V 125 128 2.50E+00 2.56E+00 2.53E+00/1.12E-04 7174 T-0302 EPC1_T 151 170 6.47E+00 1.42E+01 7.90E+00/2.21E-02 1865 T-0303 EPC2_T 139 169 6.87E+00 1.94E+01 7.79E+00/4.24E-02 1865 T-0310 RF_ISOLTR1_T 205 225 3.13E+00 1.78E+01 5.61E+00/3.03E-02 7791 T-0311 RF_ISOLTR2_T 198 214 1.23E+01 2.12E+01 1.40E+01/1.69E-02 7791 T-0312 TWT1_T 202 224 4.11E+00 1.93E+01 6.42E+00/5.06E-02 1864 T-0313 TWT2_T 190 208 1.61E+01 2.46E+01 1.77E+01/2.55E-02 1864 T-0315 USO_T 161 165 1.45E+01 1.57E+01 1.51E+01/4.33E-03 1865 T-0316 KA_AMP_T 178 213 1.30E+01 2.89E+01 1.50E+01/3.17E-02 3631 L-0200, L-0201, and T-0315 are nominal. Open Loop Data ============== Data Collection --------------- We have transferred the following open loop data to Stanford: YYYY/DDD DSS DSP SAMP BW DSP BIT REC RECS RECS MAX START STOP RATE MODE RESN LEN MSSG SNR -------- --- -------- -------- ---- ---- ---- ---- ---- ----- ---- ----- 1999/119 54 19:27:00 19:35:00 5000 2000 2 12 1666 2401 0 57.1 1999/119 54 20:07:00 20:17:00 5000 2000 2 12 1666 3001 0 57.6 1999/119 54 22:05:00 22:14:00 5000 2000 2 12 1666 2701 0 57.5 1999/119 54 23:22:00 23:31:00 5000 2000 2 12 1666 2701 0 57.1 1999/120 45 17:41:00 17:51:00 5000 2000 2 12 1666 3001 0 4.3 1999/120 45 18:59:00 19:08:00 5000 2000 2 12 1666 2701 0 59.3 Anomalies --------- An occultation beginning at 1999/119-21:24:00 was lost because of a DSP error. The occultation beginning at 1999/119-23:22:00 was lost when the HGA apparently turned away from Earth-point 18 minutes early. The recording (above) was fine, but we measured the HGA sidelobe pattern rather than an ingress occultation. Trish Priest is investigating. The occultation starting 1999/120-17:41:00 was lost because of an operator error; the recording contains only noise. Other occultations on 1999/120 were tracked by DSS 61 where remote operation of the open-loop receivers is not possible. Analyses -------- Dave Hinson has been comparing occultation inversions using data files with and without corrections for HGA motion. His report: I've retrieved two profiles from occultation 444e. The only difference is that one is corrected for motion of the HGA phase center and the other is not. The temperature difference is less than 0.4 K and is always much smaller than the 1-sigma uncertainty. The pressure difference is less than 0.4 Pa and is also smaller than the 1-sigma uncertainty throughout the profile. There is, however, a noticeable change in the frequency residuals in the baseline that suggests that the correction is helping. Joe Twicken has revised his Allan Deviation calculations included with yesterday's report. His new results: Upon further investigation by Dave and myself, it has been discovered that my pruning algorithm which selects the baseline portion of POWERFIT files for the estimation of USO frequency and Allan Deviation can use some improvement. It includes one extra sample at the time of loss of carrier which has dramatic effects on the Allan Deviation estimates when the baselines are very short. I have recalculated the Allan Deviation from the two recent occultations which I investigated. The results are below. It now appears that there has not been a problem with frequency stability since the HGA was deployed. I apologize for raising concerns about this earlier. I have recalculated the Allan Deviation for two recent occultations. The occultations were 444e and 444i, recorded at DSS 15 on 1999/104. The SNR was approximately 62 dB/Hz for each recording. I accounted for motion of the HGA phase center when making the stability estimates (using smoothing of the HGA phase center velocity in the spacecraft frame). The duration of the baseline from which I estimated the Allan deviation was less than three minutes in each case. USO Frequency: 8423153024.66 Hz (444e) 8423153024.76 Hz (444i) t, sec Allan Deviation Occn 444e Occn 444i ------- ---------- ---------- 0.4096 5.0107e-13 4.1359e-13 0.8192 2.0833e-13 2.4580e-13 1.6384 1.6713e-13 1.8113e-13 3.2768 1.4148e-13 1.4871e-13 6.5536 1.6253e-13 1.8430e-13 26.2144 4.5744e-13 4.3032e-13 Closed Loop Data ================ Data Collection --------------- We have obtained the following files from OSCAR and EPIC: Original File Name Name on SOPC -------------------------------- ------------ ODF: 99119O119_10S.SJO;1 9119119A.ODF Ancillary Data ============== Data Collection --------------- We have obtained the following files from the FIS: Original File Name Name on SOPC -------------------------------- ------------ OPT: optg_m_990428_OD0621-0623_0795_V1 9118133A.OPT SAK: mgs_solar_array_1999-118.ck 9118118A.SAK SPK: spk_m_990428_OD0621-0623_0795_V1 9118133A.SPK TCK: mgs_spice_c_kernel_1999-118.ck 9118118A.TCK We have obtained the following files from NAIF: Original File Name Name on SOPC -------------------------------- ------------ AGK: mgs_hga_ck_1999-04-28.bc 9118118A.AGK