PDS_VERSION_ID         = PDS3                                                 
RECORD_TYPE            = STREAM                                               
OBJECT                 = TEXT                                                 
  PUBLICATION_DATE     = 2012-09-27                                           
  NOTE                 = "                                                    
      TRIG_A4.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 Sounder, and the Dust           
      detector algorithm when using Trigger A4."                              
END_OBJECT           = TEXT                                                   
END                                                                           

Trigger A4 Description                                                        
                                                                              
Sequence:  S05,...                                                            
Trigger A4 ( HRSED 182 kbps Hirate Mode )                                     
                                                                              
This mode is designed to provide a hirate mode for analyzing fine structure   
of SED's, while also providing a low temporal resolution spectrum at the      
spectral 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 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:  2 MHz and 10 MHz.  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.  A Sounder measurement is scheduled every 10 minutes.            
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  Snapshot Spacing  Snapshot Length    
--------  --------------------  -------  ----------------  ---------------    
LFR       1 - 25 Hz             EX, BX   126 seconds                          
MFDR      70Hz - 1.7KHz         EX, BX   126 seconds                          
MFR       25 - 12 KHz           EX, BZ   32 seconds                           
HFR       3.6 KHz - 16 MHz      EX, EW   64 seconds                           
HFR       2 MHz or 10 MHz band  EX       2.5 seconds       2048               
WBR       2 MHz or 10 MHz band  EX       0.125 second      4096               
                                                                              
                                                                              
                                                                              
                                                                              
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       32    n    500  1              3.6-319KHz           
HF1   2E    y     y        2    n     40  1     60    25 0.325-1.825MHz       
HF2   1E    n     n        1    n     40  1     72   200 1.825-16.225MHz      
                                                                              
Bands ABC require 1.560 sec to complete, H1 requires 2.852 sec, and           
H2 requires 2.534 sec for a total of 6.946 sec per sweep.  The hfr            
cycle time is 64 seconds.