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 Time between Snapshots Samples per Snapshot
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 Langmuir 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.