Gene and Danny:

Here is the time line for the MEX BSR on day 260 (local time 17 September,
Thursday 3 AM to 8 AM) at DSS 14.

This is a strange one.  There is a DSS 14 MEX telemetry/tracking pass
immediately before the BSR (07:20-10:20).  Then there's a break for the usual
BSR pre-cal (10:20-12:20).  The BSR experiment itself is pretty tame; but the
BSR allocation is short and misaligned.  We collect surface echoes and then
go directly to the post-cal.  There is no second minical, no second slew, and
no second spacecraft carrier calibration.  The slew and carrier calibration
are scheduled on the spacecraft, but during the time when we are doing the
ground post-cal.

In fact, I have delayed the EOT 10 minutes (to 14:10) so that we can collect
the final surface reflections.  You should check with the NOPE and station to
make sure this is OK.  Considering that we usually complete the post-cal in
30 minutes (plus a few minutes to stow), I'm hoping this will not be a
problem.  If it is, then just do EOT at the official time, reset the FROs to
0, and end the 100 kHz recordings at the same time (14:00).

The spacecraft is moving away from Mars while we are getting surface echoes.
The specular point track moves from the southwest corner of Argyre Basin
(58S, 47W) into heavily cratered terrain, ending at (64S, 96W).  Incidence
angles begin at 67 deg and end at 78 deg, so RCP will always have the
stronger echoes.  The echo will be 8500 to 10200 Hz above the direct signal,
so a single X-Band FRO is sufficient for the entire observation.

The DKF wasn't very helpful in planning ground activities; I think the
generation is flawed when the track is too short.  So some of the timeline
events are uncertain.  I have based the timeline on the key BSR events in the
ESA sequence.

If you need to reach me, try 650-494-9272 until about 7:30 AM.  I will try to
call in while you're collecting echoes.  I have an 8 AM telecon at the lab
(650-723-3525), so will be moving earlier than usual anyway.

Thanks,
Dick


2009/260 (UTC)
- - - - - - -

10:20  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

12:20  Begin track (X-Band status unknown, but probably ON)

12:31  S-Band transmitter ON

12:46  X-Band telemetry OFF

       Resume 25 kHz recording (SCHAN 3)

       Ask station to switch to 'planetary' coordinates at 12:48

12:48  Station switch to 'planetary' coordinates

12:50  FRO_X = +25000  (SCHAN 3)
       FRO_S = +25000  (SCHAN 3)

12:51  Begin MINICAL #1

       Begin SLEW #1 (not visible in 25 kHz)

13:06  End MINICAL #1 (end of step 5)

       End SLEW #1

       FRO_X =  +7000 Hz (SCHAN 3)
       FRO_S =      0 Hz (SCHAN 3)

       Begin 100 kHz recordings (SCHAN 4)

       Begin surface reflections
       Expect S-Band echoes to be much weaker than X-Band
       RCP echoes stronger than LCP

13:50  Remind station of delayed EOT and no MINICAL #2 (new EOT at 14:10)

14:00  Original EOT (delay to 14:10 if OK with NOPE and station)

14:10  FRO_X = 0 Hz (SCHAN 3)
       FRO_S = 0 Hz (SCHAN 3)

       End 100 kHz recordings (SCHAN 4)

       End of track

       Go to zenith

       Begin post-cal when ready

15:00  End post-cal (or earlier, if post-cal complete)

       End 25 kHz recordings

       End of Activity