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,EW,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	Eu,Ev,Ew	32 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   325-4.1  MHz
H2    2E    y    y       1        y     80     1     61   200  4.0-16   MHz

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.