Trigger 8E Description

Sequence: S05, ...
Trigger 8E ( Survey Mode, Nighttime/Periapsis )
This mode is designed to provide a survey mode, with fast temporal resolution and spectral resolution. Both low-frequency and high-frequency WFR measurements are made, using "toggle" mode. Dust detection is included. Langmuir Probe sweeps are performed every 640 seconds. A Sounder measurement is scheduled every 10 minutes. MFDR measurements are made every 32 seconds, which provides MFR2 replacement data, while the LFR measurements are also made every 32 seconds, providing the 25-Hz LFR data.

Beginning in S03, the HFR configuration was modified, in order to improve the sensitivity for SEDs. The H2 integration period is increased to 40 ms, the H1 integration period is increased to 40 ms, and the ABC integration period is decreased to 500 ms.
Receiver Frequency Range Sensors Time between Snapshots
LFR 1 - 25 Hz EX, BX 32 seconds
MFDR 70 - 1700 Hz EX, BX 32 seconds
MFR 25 - 12 KHz EX, BZ 32 seconds
WFR 1 - 25 Hz EX,EW,BX,BY,BZ 320 seconds
WFR .1 - 2.5 KHz EX,EW,BX,BY,BZ 320 seconds
HFR 3.6 KHz - 16 MHz EX, EW 16 seconds
LP N/A Langmuir Probe 640 seconds
Sounder 3.6 - 115 KHz EX, EW 600 seconds



The HFR is in the newest version of "Nighttime Survey" mode, which now includes both auto- and cross-correlations for H1, and modified integration constants for all bands. This mode is defined by:
          Correlations     Channels        Integ.                Size Frequency
Band Ant. Auto-  Cross-    per Band   df   Period    Rep   Steps kHz  Start - Stop
---- ---- -----  ------    --------   --   ------    ---   ----- ---- ------------
ABC  2E   y         y        16       n    500       1                3.6-319 kHz
H1   2E   y         y         2       n    40        1     60    25   325k-1.8MHz
H2   1E   n         n         1       n    40        1     72   200  1.8M-16MHz
Bands ABC require 1.58 sec to complete, H1 requires 2.85 sec, and H2 requires 2.53 sec for a total of 6.97 sec per sweep. However, the time between analyses is set to 16 seconds to reduce the bit rate. Every 600 seconds the HFR normal analyses are interrupted by a Sounder analysis. Beginning in S05, the Sounder setup was modified. With the current configuration, the Sounder operation has a duration of approximately 16 seconds. This Sounder analysis is defined by:
  sounder mode:   EX AAA
  1st  sounder freq:      0
  last sounder freq:     89
  T1 delay:         5 msec
  T2 delay:         5 msec
  T3 delay:        15 msec
  passive spectra:      2
  active  spectra:      2
  # of cycles:       1
  sounder output A:      3 autos
  sounder output B:      3  AGCs