Gene and Danny:

Here is the time line for the MEX BSR on day 284 (local time 11 October,
Sunday 6:10 AM to 11:25 AM) at DSS 14.

Gene has already noticed that the S-Band activities may be limited.  But
let's assume the DSN Keyword File (DKF) is wrong and run all the RSRs anyway;
the DKF has had occasional problems in the past.  It would be a shame to miss
echoes if they were there.  According to the DKF, there's 6 seconds of S-Band
carrier between 15:18:14 and 15:18:20 if the DKF IS right and you want to
test your skills at observing transient phenomena.

After BOT there is about 15 minutes of X-Band telemetry before the BSR
activities get under way and about 4 minutes after; I'll leave it to you and
the NOPE as to whether you pursue these.  The microwave configuration should
not be changed to get the telemetry.

The X-Band surface echo should start just below the carrier with LCP stronger
than RCP.  The echo drifts to higher frequencies and gets weaker; we use one
FRO at 25 kHz to keep it in the passband.  At the end the echo is about 13
kHz above the carrier, and RCP should be significantly stronger than LCP.  S-
Band will need no FRO, assuming there's a signal.

The reflecting region is in southern cratered terrain; I'm not expecting the
signal to change much during the hour -- except for getting weaker as the
spacecraft moves to higher altitude.  The start is near (41S, 151E) and the
end is near (57S, 134E).  About when we add the FRO, the specular point is
between two craters named Kepler and Tycho Brahe; maybe these giants of
astronomy will help us be successful in collecting the data.

If you need to reach me, try 650-494-9272.  I get back to SFO from the DPS
meeting the previous night about 6:30 PM and should have had a reasonable
night's sleep by the time you begin.  I'll plan to give you a call at some
point, but the memory may not be fully functional after a week on the road.

Thanks,
Dick


2009/284 (UTC)
- - - - - - -

13:10  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

15:10  Begin track (X-Band status unknown but probably OFF)

15:16  Resume 25 kHz recording

15:18:14  S-Band ON

15:18:20  S-Band OFF

          X-Band ON (telemetry ON)

15:33  X-Band telemetry OFF

       Ask station to switch to 'planetary' coordinates at 15:38

15:38  Station switch to 'planetary' coordinates

15:40  FRO_X = +25000  (SCHAN 3)
       FRO_S = +25000  (SCHAN 3)

15:41  Begin MINICAL #1

15:42  Begin SLEW #1 (not visible in 25 kHz)

15:56  End MINICAL #1 (end of step 5)

       End SLEW #1

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

       Begin 100 kHz recordings (SCHAN 4)

       Begin surface reflections
       LCP echoes stronger than RCP

16:20  FRO_X = +5000 Hz (SCHAN 3)

17:00  Remind station of MINICAL #2 starting at 17:05

17:03  FRO_X = +25000 Hz (SCHAN 3)
       FRO_S = +25000 Hz (SCHAN 3)

       End 100 kHz recordings (SCHAN 4)

       Begin SLEW #2 (not visible in 25 kHz)

17:05  Begin MINICAL #2

17:11  End SLEW #2 (not visible in 25 kHz)

17:18  Remind station to return to spacecraft pointing at 17:20

17:20  End MINICAL #2 (end of step 5)

       DSS 14 return to spacecraft pointing predicts

17:21  X-Band telemetry ON

17:25  X-Band OFF

       End of track

       Go to zenith

       Begin post-cal when ready

18:25  End post-cal (or earlier, if post-cal complete)

       End 25 kHz recordings

       End of Activity