PDS_VERSION_ID         = PDS3                                                 
RECORD_TYPE            = STREAM                                               
OBJECT                 = TEXT                                                 
  PUBLICATION_DATE     = 2006-12-19                                           
  NOTE                 = "                                                    
      TRIG_B8.TXT describes the RPWS instrument configuration for the         
      High Frequency Receiver (HFR), the Medium Frequency Receiver            
      (MFR), the Low Frequency Receiver (LFR), the Waveform Receiver          
      (WFR), the Langmiur Probe (LP), and the Sounder when using Trigger      
      B8."                                                                    
END_OBJECT           = TEXT                                                   
END                                                                           

Trigger B8 Description                                                        
                                                                              
Sequence:  C37, ...                                                           
Trigger B8 ( MAGTAIL )                                                        
This mode assumes a background survey mode, such as 8A or 8E, is running,     
and on top of that overlays fast WFR data acquisition.  In order to do this,  
the LFR data acquisition is changed to acquire data every 48 seconds, so      
that the WFR data can be done at this rate also.  The WFR is run in toggle    
mode.  A WFR snapshot, in its nominal 5-channel and 2048-sample mode, is      
acquired every 48 seconds, giving an elevated rate.  In addition to limiting  
the LFR data acquisition, the data compression algorithm for the WFR is       
changed to "packed" mode, so that this faster data rate can be accomplished.  
The target bit rate is 3000 bps.  During C37, in a short test, the measured   
bit rate was 3000 bps; this was using trigger 8A as the background trigger.   
                                                                              
Receiver  Frequency Range   Sensors         Snapshot Spacing                  
--------  ----------------  --------------  ----------------                  
LFR       1 - 25 Hz         EX, BX          96 seconds                        
MFR       25 - 12 KHz       EX, BZ          32 seconds                        
MFDR      200 - 1400 Hz     EX, BX          96 seconds                        
WFR       1 - 25 Hz         EX,EW,BX,BY,BZ  96 seconds                        
WFR       .1 - 2.5 KHz      EX,EW,BX,BY,BZ  96 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 a modified "Composite Survey" mode, which now includes both     
auto- and cross-correlations for H1.  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  80     1   60    25   325k-1.8MHz          
H2   1E   n        n      1     n  20     1   72    200  1.8M-16MHz           
                                                                              
Bands ABC require 3.16 sec to complete, H1 requires 5.47 sec, and H2          
requires 1.46 sec for a total of 10.09 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.  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