PDS_VERSION_ID         = PDS3                                                 
RECORD_TYPE            = STREAM                                               
OBJECT                 = TEXT                                                 
  PUBLICATION_DATE     = 2007-09-23                                           
  NOTE                 = "                                                    
      TRIG_BC.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 Wideband Reciever (WBR), the Langmiur Probe (LP), the        
      Sounder, and the Dust detector algorithm when using Trigger BC."        
END_OBJECT           = TEXT                                                   
END                                                                           

Trigger BC Description                                                        
                                                                              
Sequence:  C38, C39, ...                                                      
Trigger BC ( HRSKR 182 kbps Hirate Mode )                                     
                                                                              
This mode is designed to provide a hirate mode for analyzing fine structure   
of SKR, while also providing a low temporal resolution spectrum at the        
nominal frequency resolution.  This is accomplished by running the WBR in     
the "down-convert" mode, using the 25-KHz wide signal provided by the HFR,    
which is simultaneously running in millisecond at the frequency provided to   
the WBR.  This mode of operation is paused every 64 seconds for 8 seconds,    
in order to perform a normal analysis sweep, nominally in SEDDF mode.  At     
this time, the LFDR/MFDR is also sampled.  These provide the low temporal     
resolution spectrum.  At each 64-second interval the millisecond mode         
frequency is toggled between each of two selections:  225 kHz and 325 kHz.    
These frequencies could be tweaked with additional commands.  WFR data        
acquisition and Dust detection are not done.  Langmuir Probe sweeps are       
performed every 640 seconds.  The Sounder is disabled in this trigger.        
It is assumed that prior to this trigger, either trigger A0 (SEDDF) or        
trigger 8E (Night-Time Survey) was in effect.                                 
                                                                              
Receiver Frequency Range         Sensors Cycle Time         Snapshot Size     
-------- ----------------------- ------- ------------------ -------------     
LFR      1 - 25 Hz               EX, BX  128 seconds                          
MFDR     70 - 1700 Hz            EX, BX  128 seconds                          
MFR      25 - 12 KHz             EX, BZ  32 seconds                           
HFR      3.6 KHz - 16 MHz        EX, EW  64 seconds                           
HFR      225 kHz or 325 kHz band EX      about 2.25 seconds 2048              
WBR      2 MHz or 10 MHz band    EX      0.125 second       4096              
LP       N/A                     Probe   640 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.  This fits into the      
8-second slot allowed for the normal analysis performed every 64 seconds.