PDS_VERSION = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 1997-04-04 NOTE = "MGS RST Instrument Health Report HEA7094A.TXT" END_OBJECT = TEXT END Dick Simpson is out of the office until Thursday, April 10. This report is being submitted by Joe Twicken. I will be traveling to LMA Denver on Monday and Tuesday next week. RST Health report delivery may be interrupted as a result. Engineering Data ================ Engineering Data Statistical Summary from CSV2STAT: First SCET: 1997-04-03T06:16:16.551 Last SCET: 1997-04-03T23:59:52.548 CHANNL CHANNEL TITLE DN-LO DN-HI EU-LO EU-HI EU-AVG/STDEV RECDS ------ ------------- ----- ----- --------- --------- ---------/-------- ----- L-0037 MOT1_USO_ENA 0 0 1163 L-0047 MOT2_USO_ENA 1 1 1163 L-0053 RF_SW_OSC 2 2 1163 L-0060 TWTA1_FILMNT 0 0 1163 L-0061 TWTA1_HV 0 0 1165 L-0070 TWTA2_FILMNT 1 1 1165 L-0071 TWTA2_HV 0 0 1163 L-0080 USO_PWR 0 0 1163 L-0090 KaBLE_STAT 0 1 1163 L-0091 KaBLE_ENABLE 0 0 1165 L-0111 MOT1_RCV_AGC 174 255 -1.53E+02 -1.27E+02 -1.33E+02/2.04E-01 1163 L-0121 MOT2_RCV_AGC 128 255 -1.53E+02 -1.14E+02 -1.21E+02/3.38E-01 1163 L-0131 TWTA1_HLX_I 0 1 -3.84E-02 -1.85E-02 -3.82E-02/4.81E-05 1163 L-0132 TWTA1_ANOD_V 0 0 -1.00E+03 -1.00E+03 -1.00E+03/0.00E+00 144 L-0141 TWTA2_HLX_I 38 42 7.05E-01 7.85E-01 7.52E-01/4.45E-04 1163 L-0142 TWTA2_ANOD_V 59 63 -8.70E+02 -8.62E+02 -8.66E+02/1.29E-01 144 L-0200 USO_REG_V 203 205 4.06E+00 4.10E+00 4.08E+00/6.23E-04 143 L-0201 USO_OVEN_V 124 126 2.48E+00 2.52E+00 2.50E+00/6.54E-04 143 T-0302 EPC1_T 127 146 1.64E+01 2.46E+01 2.18E+01/1.83E-01 144 T-0303 EPC2_T 119 149 1.51E+01 2.81E+01 2.30E+01/3.14E-01 144 T-0310 RF_ISOLTR1_T 190 214 1.23E+01 2.46E+01 2.01E+01/9.96E-02 1163 T-0311 RF_ISOLTR2_T 179 198 2.12E+01 2.86E+01 2.61E+01/5.87E-02 1163 T-0312 TWT1_T 187 214 1.23E+01 2.57E+01 1.97E+01/3.11E-01 144 T-0313 TWT2_T 173 194 2.29E+01 3.07E+01 2.76E+01/1.78E-01 144 T-0315 USO_T 170 172 1.24E+01 1.30E+01 1.26E+01/1.46E-02 144 T-0316 KA_AMP_T 159 204 1.83E+01 3.56E+01 2.54E+01/4.44E-01 145 L-0200, L-0201 and T-0315 remain nominal. KaBLE (L-0090) went off at approximately 07:33. T-0302, T-0303, T-0310, T-0311, T-0312, T-0313 and T-0316 began significant temperature drops at that time. Open Loop Data ============== Data Collection --------------- No new data. Analyses -------- My report on USO Test #10 (97/092) follows. Three things were notable about this test. First, the power spectra showed a series of frequency spurs in the vicinity of the carrier. Second, telemetry was off and the resulting SNR was the highest we have seen to date. Third, the USO frequency stability (Allan deviation) was the best we have seen in the USO Tests to date at all integration times: "I have processed the ODS data from 97/092. This ODS was recorded at DSS 15. The data were acquired as part of USO Test #10. The SNR was approximately 61 dB/Hz during the Test. This was the sixth USO test since the MGS HGA was deployed. All files for processing this ODS were recorded in the MgsDB database. "The first 57 minutes of USO Test data were not recorded due to an error at the DSP. At the beginning of the USO Test, the DSP gave a warning message: NO BUFFERS AVAILABLE FOR ALLOCATION. The station had to reboot the DSP in order to clear the error and the recording did not begin until nearly half of the test was over. "The ODS was acquired at DSS 15 from 05:57:30 to 07:00:00 at 5000 samples per second in mode 2 (1250 12-bit samples/second for each of 4 A/D's). KaBLE was on during this test, referenced to a combination of USO and VCO. Telemetry and ranging were both off. There were no missing records in the ODS. "I used the spk_c_970129-970510 SP-kernel file to steer the data. This file was created on 97/083. The POCA file was fixed with our "salvagePoca" program, but hand modification of the POCA file was also required. At time tag 21639, it was necessary to modify the ramp rate from -0.07090 Hz/sec to -0.07089 Hz/sec in order to maintain consistency with remaining POCA readback frequencies. It has also been necessary to make such a 10 microHertz/sec modification to a POCA ramp rate a few times in the past, in order to match the POCA readback frequency at the time of a ramp rate change. The cause of this 10 microHertz mismatch is not known. In addition to that POCA error, there was the usual collection of missing/duplicate POCA time tags and incorrect POCA readback frequencies. These were all handled by the salvagePoca program. "The power spectra of the USO Test #10 signal showed a comb of frequency spurs which tracked the carrier throughout the Test. I have not seen this behavior prior to this Test. The primary spurs were at 60 Hz and many harmonics of 60 Hz on both sides of the carrier. The 60 Hz spurs were approximately 38 dB below that of the carrier and the harmonics were all 42 or more dB below the carrier. In addition to these spurs, the steered data showed numerous other lower-level spurs tracking the carrier. The closest spurs to the carrier were a set of side-by-side spurs which appeared both above and below the carrier with an offset of approximately 30 Hz. The spurs which we have previously seen at approximately 650 Hz from the carrier were not evident in this Test. "A large amplitude modulation with a period of about 6-12 minutes is evident in the carrier amplitude estimates. The peak-to-peak variation during this test was on the order of 1-2 dB. "I estimated the USO frequency to be 8423152935.19 Hz. The best linear fit to the USO frequency since 96/332 has a slope of 0.253 Hz/day. This fit is actually quite good. The 1-sigma error between our USO frequency estimates since 96/332 and the best linear fit to them is 0.23 Hz. "The Allan deviation for this recording is shown below. The SNR during the acquisition of data was approximately 61 dB/Hz. This value may be somewhat underestimated due to the many spurious frequency components in the vicinity of the carrier. I did not compensate for the spacecraft spin cycle. AT ALL INTEGRATION TIMES, THIS WAS THE BEST USO TEST PERFORMANCE TO DATE. t (sec) AD ------ ---------- 0.4096 2.6101e-13 1.6384 1.7441e-13 3.2768 1.4299e-13 6.5536 1.1348e-13 26.2144 8.9345e-14 Closed Loop Data ================ No new data. Data Collection --------------- We have obtained the following files from OSCAR and EPIC: Original File Name Name on SOPC ------------------------------ ------------ ATDF: ODF: IONCAL: TROPCAL: WEATHER: UTPM: EOP: