Trigger 80 Description

Sequence: C21
Trigger 80 (Direction-Finding Survey)
This mode is designed to provide a Survey with fast temporal resolution and standard spectral resolution for cruise periods following Earth Swing-by. Periodic Waveform measurements are made. The entire RPWS frequency range (1 Hz - 16 MHz) is covered.

Receiver	Frequency Range	Sensors	Time between Snapshots
LFR	1 - 25 Hz	EX, BX	16 seconds
MFR	25 - 12 KHz	EW, BZ	32 seconds
WFR	.1 - 2.5 KHz	EX, EW, BX, BY, BZ	160 seconds
HFR	3.6 KHz - 16 MHz	EU, EV, EW	32 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    20        1     76    50   325k-4.1MHz
H2   2E   y         y         1       y    20        1     61    200  4.0M-16MHz

Bands ABC require 1.69 sec to complete, H1 requires 3.84 sec, and H2 requires 3.07 sec for a total of 8.60 sec per sweep. However, to allow time for LFR and MFR snapshots to occur without interference, and also to limit the bitrate, one complete sweep is done every 32 seconds. To avoid the interference from the DF mode, the MFR uses the EW antenna.