Gene, Danny:


Here is the time line for the MEX BSR on 19 April.

I'm returning from the MEX/VEX meetings in Cologne when this one takes place.
Although I may be able to call in by phone, I don't think we should count on
it; and I may not be of much help anyway because of fatigue.

This experiment looks very much like the one conducted on 11 April except
that it is being done at DSS 63 (and the local time at JPL is about 12 hours
different).  The spacecraft is near apoapsis, the echo is narrow, and it
barely moves in frequency.

The downside is that the echoes will be weak, especially at S-Band because of
the high spacecraft altitude; and the X-Band carrier will be outside the 25
kHz window while you are watching the echo.

This one also has a lot going on in the first few minutes (after BOT).
Getting to BOT early would help.  If switching to 'planetary coordinates' is
going to be difficult, skip it,  The effect of using 'planetary' is
negligible for this experiment -- we're just getting into the habit for later
in the year when it WILL be more important.

I'm building this timeline using fairly old predict files; but I doubt the
final files would lead to any significant changes.

Let me know if you notice any problems.  I'm on vacation and completely out
of e-mail range from today until 13 April.  I'll be in the Stanford area for
about 24 hours and then off to Cologne on the evening of 14th.  After that, I
may have occasional e-mail connections until I leave Cologne.  You should use
this e-mail account (hut.coord@yahoo.com) to contact me; my Sanford e-mail is
not accessible except when I am physically at the University.

There's another MEX BSR on 25 April, after I've been home for a while.  It
should be very much like this one except there's more time to do things
around BOT.


Thanks and good luck,
Dick





2009/109 (UTC)
- - - - - - -

03:35  Begin Pre-cal at DSS 14
       FGAIN = 60 dB (all channels, including X-RCP)
       FRO_X = 0; FRO_S = 0 (all SCHAN)
       Start 4-channel 25 kHz recordings after Step 4
       Stop 25 kHz recording after Step 18

05:21  S-Band Tx ON (X-Band status unknown, but probably ON)

05:35  Begin track (X-Band and S-Band Tx should both be ON)

       Ask station to prepare for switching to planetary coordinates

05:36  Resume 25 kHz recording (SCHAN 3)

05:45  Begin SLEW #1

05:46  Ask station to switch to "planetary pointing" (center of Mars)

05:49  FRO_X = +21000 Hz (SCHAN 3)
       FRO_S =  +3000 Hz (SCHAN 3)

       FRO_X = +11000 Hz (SCHAN 4)

05:50  Begin Minical #1

06:05  End Minical #1 (end of Step 5)

06:14  Begin 4-channel 100 kHz recordings (SCHAN 4)

06:15  End SLEW #1
       Begin surface reflections

       Expect X-RCP and X-LCP to have similar magnitudes
       Expect S-RCP and S-LCP to have similar magnitudes, both weaker than X
       Echoes drift slowly to right during the hour; RCP should get stronger

07:20  End surface reflections
       Begin SLEW #2

       End 100 kHz recordings

07:21  Begin Minical #2

07:36  End Minical #2 (end of step 5)

07:45  FRO_X = 0
       FRO_S = 0

07:50  End SLEW #2

08:00  EOT
       Move antenna to zenith
       Begin post-cal when ready

09:00  End post-cal (OK to end early if post-cal complete)

       End 25 kHz recordings

       End of Activity