Trigger 76 Description
Sequence: C21, etc.
Trigger 76 ( Titan low-rate Langmuir Probe Mode )
This mode is designed to provide a survey mode, with standard temporal resolution and
spectral resolution, and with increased Langmuir Probe measurements designed for Titan flybys.
High-frequency WFR measurements are made. Langmuir Probe sweeps are performed
every 16 seconds using the down-up ramp bias function. Between the 1-second sweeps,
20-Hz LP density measurements are done. No Sounder or Dust measurements are made.
The HFR is in Composite Mode Survey. During Cruise, this mode has been used periodically
to monitor Spacecraft potential and photoelectrons.
| Receiver |
Frequency Range |
Sensors |
Time between Snapshots |
| LFR |
1 - 25 Hz |
EX, BX |
32 seconds |
| MFR |
25 - 12 KHz |
EX, BZ |
32 seconds |
| WFR |
0.1 - 2.5 KHz |
EX,EW,BX,BY,BZ |
320 seconds |
| HFR |
3.6 KHz - 16 MHz |
EX, EW |
10.375 seconds |
| LP |
N/A |
Langmuir Probe |
16 seconds |
The HFR is in a modified "Composite Survey" mode, which now includes
both auto- and cross-correlations for H1. Prior to C28, this mode
did not include auto-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, a small amount of additional time is
required for commanding and data formatting, resulting in a 10.375 cycle time.