Trigger 80 Description

Sequence: C40, ...
Trigger 80 ( Direction-Finding Survey )
This mode is designed to provide a direction-finding survey mode, with standard 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. The Sounder is disabled. WFR measurements are made every 32 seconds, which provides both LFR and MFR2 replacement data via ground processing of the WFR data. However, the snapshot length is set to 512 samples in order to avoid interference from the HFR, which is in direction-finding mode

Receiver Frequency Range Sensors Time between Snapshots
MFR 25 - 12 KHz EX, BZ 32 seconds
WFR 1 - 25 Hz EX,EW,BX,BY,BZ 64 seconds
WFR .1 - 2.5 KHz EX,EW,BX,BY,BZ 64 seconds
HFR 3.6 KHz - 16 MHz EX, EW 16 seconds
LP N/A Langmuir Probe 640 seconds


The HFR is in direction-finding mode for its entire frequency range from 3.6 KHz to 16 MHz. Thus, measurements are made on all three monopoles EU, EV and EW. 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         8       y    250       1                3.6-319 kHz
H1   2E   y         y         1       y    80        1     76    50   325k-4.1MHz
H2   2E   y         y         1       y    80        1     61    200  4.0M-16MHz
Bands ABC require 1.69 sec to complete, H1 requires 13.06 sec, and H2 requires 10.50 sec for a total of 25.25 sec per sweep. However, to allow time for WFR and MFR snapshots to occur without interference, one complete sweep is done every 32 seconds. To avoid the interference from the DF mode, the MFR uses the EW antenna.