Trigger A4 Description
Sequence: C34, C35
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 |
Time between Snapshots |
Snapshot Length |
| LFR |
1 - 25 Hz |
EX, BX |
64 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 |
2.25 seconds |
2048 |
| WBR |
2 MHz or 10 MHz band |
EX |
0.125 second |
4096 |
| LP |
N/A |
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. This fits into the 8-second slot allowed for the
normal analysis performed every 64 seconds.
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