Trigger B4 Description
Sequence: C38, ...
Trigger B4 ( Titan deltaN/N mode)
This mode assumes a background survey mode, such as 8A or A0, is running.
The duty cycle of the Langmuir Probe and the WFR are increased. The WFR
is connected in 3-channel mode to the two voltage-biased cycliners,
EU and EV, and their voltage is set to +5V. The third WFR channel is
connected to the LP sphere, which is biased at +4V. Every 10 seconds a
1024-sample (per channel) data set is acquired by the WFR in 2.5KHz mode.
The Langmuir Probe performs a sweep every 20 seconds and between sweeps,
does a 256-sample density mode measurement at 20 Hz. The MFR is connected
to the EW antenna, since the EX antenna is being used in deltaN/N mode.
Also the LFDR and MFDR use the EW antenna for their electric field
measurements (in addition to the BX antenna). They each acquire data
once a minute. The WBR acquires data in 80-KHz mode.
Sounder is disabled, and dust detection is disabled in this mode.
The target bit rate is 100 kbps. Measured bitrate was about 55 kbps
when in S&ER-3 mode, measured during C39. In C40, at a higher rate
telemetry mode, the measured bitrate was 99 kbps.
| Receiver |
Frequency Range |
Sensors |
Time between Snapshots |
| MFR |
25 - 12 KHz |
EW, BZ |
32 seconds |
| WFR |
.1 - 2.5 KHz |
EU(+5V),EV(+5V),LP(+4V) |
10 seconds |
| HFR |
3.6 KHz - 16 MHz |
EX, EW |
10 seconds |
| LP |
N/A |
Langmuir Probe |
20 seconds |
| WBR |
0 - 80 KHz |
EX |
0.125 second |
The HFR is in a modified "Composite Survey" mode, which includes
both auto- and cross-correlations for H1, and should be set up
to use the faster integration constants of the "Night-time" survey
mode, running either trigger 8E or A0 or A8 prior to this trigger.
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. However, the time between analyses is set to 10
seconds to avoid interference from the LP sweep.
No Sounder measurements are made in this mode. No onboard dust detection is done either.