Trigger A0 Description

Sequence: C34, C35
Trigger A0 ( SEDDF Mode )

This mode is designed to provide a Survey mode capable of detecting SED's and doing 2-antenna direction-finding on them, with standard temporal resolution and spectral resolution. Both low-frequency and high-frequency WFR measurements are made, using a "toggle" mode, although a fixed gain (maximum) rather than an auto gain mode is required until a future software update, scheduled for C35 (FSW V2.6). Dust detection is included. Langmuir Probe sweeps are performed every 640 seconds. A Sounder measurement is scheduled every 10 minutes. LFDR measurements are now made every 16 seconds, in anticipation of the LFDR toggle mode, coming with FSW V2.6, which will provide MFR2 replacement data. The HFR uses shorter integration constants for H1 and H2, with the goal to detect SED's, and it is run twice as fast as the other survey modes.

Receiver Frequency Range Sensors Time between Snapshots
LFR 1 - 25 Hz EX, BX 16 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 8 seconds
LP N/A Langmuir Probe 640 seconds
Sounder 3.6 - 115 KHz EX, EW 600 seconds



The HFR is in a modified "Composite Survey" mode, which now includes both auto- and cross-correlations for H1, and differs from standard Survey mode in that its integration constants for H1 and H2 are shorter. 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    1000      1                3.6-319 kHz
H1   2E   y         y         2       n    20        1     60    25   325k-1.8MHz
H2   1E   n         n         1       n    10        1     72    200  1.8M-16MHz
Bands ABC require 3.16 sec to complete, H1 requires 1.57 sec, and H2 requires 0.65 sec for a total of 5.62 sec per sweep. However, the time between analyses is set to 8 seconds to reduce the bit rate. Every 600 seconds the HFR normal analyses are interrupted by a Sounder analysis. The Sounder operation has a duration of approximately 40 seconds. This Sounder analysis is defined by: 
  sounder mode:   EZ AAA
  1st  sounder freq:      0
  last sounder freq:     89
  T1 delay:        10 msec
  T2 delay:        25 msec
  T3 delay:        25 msec
  passive spectra:      2
  active  spectra:      2
  # of cycles:       1
  sounder output A:      3 autos
  sounder output B:      3  AGCs