PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 1999-09-07 NOTE = " E-mail and other messages concerning MGS Radio Science on or about 1997/061." END_OBJECT = TEXT END From trish@zygra.Jpl.Nasa.Gov Mon Mar 3 02:39:40 1997 Received: (from trish@localhost) by zygra.Jpl.Nasa.Gov (8.8.5/8.6.6) id CAA14396; Mon, 3 Mar 1997 02:38:24 -0800 (PST) From: Trish Priest Message-Id: <199703031038.CAA14396@zygra.Jpl.Nasa.Gov> Subject: USO Test #8 To: rsimpson@magellan.stanford.edu, joe@neptune.stanford.edu Date: Mon, 3 Mar 1997 02:38:24 -0800 (PST) Cc: trish@zygra.JPL.NASA.GOV X-Mailer: ELM [version 2.4 PL24] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Status: RO Hello, USO Test #8 went well. I am currently in the middle of the retransmission. This was a four hour test from 12:31:50 to 16:31:51 UTC ERT. This was over station 45, and it was in the standard configuration. The latest SOE for this test should be c0505.02.soe. KaBLE was on for the first half hour of the test, and it was off for the remainder of the time. The retransmission should be complete at least three hours before you read this. -Trish ------------------------------------------------------------------------ From trish@qmail.jpl.nasa.gov Mon Mar 3 09:13:50 1997 Message-Id: Date: 3 Mar 1997 09:12:37 -0800 From: "Trish Priest" Subject: Re: USO Test To: "Richard Simpson" Cc: "Joe Twicken" X-Mailer: Mail*Link SMTP-QM 3.0.2 Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; Name="Message Body" Content-Transfer-Encoding: quoted-printable Status: RO Reply to: RE>USO Test KaBLE was on before the USO Test started, and it turned off at 13:27:50 UTC ERT. -Trish ------------------------------------------------------------------------- From joe Wed Mar 5 16:24:00 1997 Received: from neptune.stanford.edu. (neptune.Stanford.EDU [36.10.0.149]) by nova.stanford.edu (8.8.5/8.8.4) with SMTP id QAA18421; Wed, 5 Mar 1997 16:23:37 -0800 (PST) Date: Wed, 5 Mar 1997 16:23:37 -0800 (PST) From: Joe Twicken Message-Id: <199703060023.QAA18421@nova.stanford.edu> To: David.D.Morabito@cc2mhb.jpl.nasa.gov, hinson@nova.stanford.edu, john@oberon.jpl.nasa.gov, len@nova.stanford.edu, rsimpson@nova.stanford.edu, trish@qmail.jpl.nasa.gov, wls@kamel.jpl.nasa.gov Subject: USO Test #8 (97/061) Status: RO I have processed the ODS data from 97/061. Open loop data was first recorded for approximately one hour on that date with KaBLE on followed by a three hour recording with KaBLE off. The data were acquired at DSS 45 as part of USO Test #8. The SNR was approximately 55 dB/Hz with KaBLE both on and off. This was the fifth USO test since the HGA was deployed. The data files and processing steps for this Test were recorded in our MgsDB database. I processed the USO Test #8 data separately with KaBLE on and off. The ODS data for each part of the Test were transfered with separate TOT queries. As described by Dick Simpson in one of his daily health reports, there were some problems with the first query. Nevertheless, the ODS data that we did receive had been retransmitted from the station and there were no missing or duplicate records. The first ODS that I processed was acquired at DSS 45 from 12:31:50 to 13:27:50. The second ODS was acquired at the same station from 13:27:50 to 16:31:50. Both data sets were acquired at 5000 samples per second in mode 2 (1250 12-bit samples/second for each of 4 A/D's). There were no attenuation changes or other operations problems during the Test. The signal level in the second ODS did jump by a few dB, however, at approximately 16:00 hours. The cause for this jump is not known. I used the spk_c_970106-970419 SP-kernel file to steer the data. This file was created on 97/050. Both POCA files (KaBLE on and off) were fixed with our "salvagePoca" program. Once again, no hand modification of the POCA file was required. A very brief analysis of the original POCA files indicated that there were over 45 POCA records in error in the first ODS and 150 POCA records in error in the second ODS. The errors were not confined to error bursts as in the previous USO Test. During the full 4 hour recording there were a total of 14400 POCA records. An amplitude modulation with a period of about 5 minutes is evident in all the carrier amplitude estimates. Amplitude modulations have been seen in all USO Tests since the deployment of the HGA. The peak-to-peak variation during this test was on the order of 0.5 dB. This was somewhat larger than the modulation seen in the last couple of tests. The source of this modulation remains unknown. As in many previous tests, there were also a pair of frequency spurs at approximately 650 Hz on either side of the carrier. In this test, the level of these spurs was about 35 dB below that of the carrier. The spurs appear to drift through the spectrum along with the carrier. There were also spurs at 60, 180 and 300 Hz which did not drift with the carrier. The amplitude modulations and all frequency spurs were present with KaBLE both on and off. I estimated the USO frequency to be 8423152927.46 Hz. The best linear fit to the USO frequency since 96/332 has a slope of 0.254 Hz/day. This fit is actually quite good. The Allan deviation for the two recordings is shown below. The SNR during the acquisition of data was approximately 55 dB/Hz. I did not compensate for the spacecraft spin cycle. The measurements with KaBLE on and off are quite comparable, though at the longest integration time the Allan deviation increased slightly with KaBLE on but not with KaBLE off. In both KaBLE conditions, there were occasional random spikes in the frequency residuals at the shortest integration time (0.4 seconds) with amplitudes from 30 to 50 mHz. John Armstrong has noted such spikes in his 200 Hz GWE data, though the spikes he has noticed have been periodic with a period of 209 seconds. KaBLE on: t (sec) AD ------ ---------- 0.4096 3.5506e-13 1.6384 2.0431e-13 3.2768 1.5919e-13 6.5536 1.1744e-13 26.2144 1.2283e-13 KaBLE off: t (sec) AD ------ ---------- 0.4096 3.5070e-13 1.6384 2.1202e-13 3.2768 1.5808e-13 6.5536 1.2360e-13 26.2144 1.1357e-13 There was some discussion at the most recent MGS RST meeting about the quality of data from DSS 45. In our first USO Test at DSS 45 (#6), the Allan Deviation was rather poor. In this Test at DSS 45, the Allan Deviation was quite good in comparison with Tests at other stations. I will keep watch on this. Plots, as usual, are in the notebook in room 222. Joe