17 June 2004 To: Art Freiley From: Dick Simpson Subject: Noise Calibrations at DSS 14 Table below summarizes RSR results from noise measurements made at DSS 14. For 20 May, X-RCP, S-RCP, S-LCP, and now X-LCP data have been analyzed. The last has been delayed by the usual many interruptions that seem to have become part of normal life. The methods described in my previous memos were applied here. Tndu is the noise diode temperature from comparing ambient load levels with levels when the noise diode was added to the ambient load. Tndl is the noise diode temperature from comparing sky noise levels (zenith) with and without the noise diode; a nearby Top was taken to be the reference. Channel Quantity Date N Minimum Maximum Average ------- -------- ---------- -- ------- ------- ------- S-LCP Tndu 2004-04-08 4 11.30 12.20 11.60 S-RCP Top 2004-04-08 3 19.75 20.27 S-RCP Tndu 2004-04-08 2 14.67 15.74 S-RCP Tndl 2004-04-08 2 16.25 16.34 X-LCP Top 2004-04-08 2 18.48 18.49 X-LCP Tndu 2004-04-08 2 16.25 16.34 X-LCP Tndl 2004-04-08 2 17.16 17.76 X-RCP Top 2004-04-08 3 19.60 19.85 X-RCP Tndu 2004-04-08 2 20.48 22.96 X-RCP Tndl 2004-04-08 2 21.58 22.20 S-LCP Top 2004-05-13 5 23.49 24.16 23.71 S-LCP Tndu 2004-05-13 3 12.07 12.93 12.58 S-LCP Tndl 2004-05-13 3 12.08 12.36 12.20 S-RCP Top 2004-05-13 7 19.08 19.28 19.13 S-RCP Tndu 2004-05-13 4 15.60 16.16 15.81 S-RCP Tndl 2004-05-13 4 16.06 16.10 16.09 X-LCP Top 2004-05-13 10 17.16 17.37 17.28 X-LCP Tndu 2004-05-13 3 15.35 17.31 16.28 X-LCP Tndl 2004-05-13 3 17.40 17.60 17.50 X-RCP Top 2004-05-13 1 18.34 X-RCP Tndu 2004-05-13 1 23.76 X-RCP Tndl 2004-05-13 1 23.58 S-LCP Top 2004-05-20 3 23.57 23.89 23.75 S-LCP Tndu 2004-05-20 4 11.36 12.07 11.75 S-LCP Tndl 2004-05-20 2 11.82 12.04 11.93 S-RCP Top 2004-05-20 3 18.73 19.08 18.85 S-RCP Tndu 2004-05-20 5 14.83 16.49 15.99 S-RCP Tndl 2004-05-20 3 15.82 15.86 15.83 X-LCP Top 2004-05-20 4 17.38 17.57 17.48 X-LCP Tndu 2004-05-20 3 15.91 18.87 17.24 X-LCP Tndl 2004-05-20 3 17.12 17.73 17.42 X-RCP Top 2004-05-20 5 18.38 18.67 18.49 X-RCP Tndu 2004-05-20 2 22.60 23.05 22.83 X-RCP Tndl 2004-05-20 2 23.25 23.37 23.31 Although there are some variations, the results from 13 and 20 May continue to look consistent; the biggest difference is in the noise diode temperature on S-LCP. There seems to be a lot of scatter in the Tndu values from both 2004-05- 13 and 2004-05-20. The average Tndu is 1.22K lower than the average Tndl on 2004-05-13; but the average Tndl on 2004-05-13 and both averages on 2004-05-20 look good. I'll attach the X-LCP spreadsheet to this message and will FAX the plots of log(power) versus time. You may actually receive the FAX first because our e-mail server is down this morning. I have heard nothing from the PI about scheduling more observations. The MARSIS antenna deployment on the spacecraft has been postponed again. But the spacecraft will be at solar conjunction in another three months, so science incentive is minimal. I think, however, that we have demonstrated that accurate power measurements can be achieved on four channels simultaneously and look forward to putting the new procedures into practice. Thanks again for your help.