Trigger 46 Description
Sequence: C34, C35
Trigger 46 ( 80 KHz WBR cyclic turn-on, with compression)
This trigger is designed to overlay 80-KHz Wideband Receiver data on top of a standard background trigger,
such as 8A (Survey), 8E (night-time survey), or A0 (SEDDF). Data acquisition continues
for all receivers, with the exception of the dust detector and the sounder, which are disabled
during this trigger's operation. In addition, the MFR is switched to the EZ antenna to avoid
interfering with the WBR, which is assumed to be connected to the EX antenna.
It is assumed that the WBR is pre-configured before this trigger is executed, except
that the 80-KHz band selection is done by the trigger. The standard setup done for the
WBR by the background triggers is detailed below. The standard setup includes compressing the
WBR data using the Data Compression Chip (DCC), and to use this capability the WBR can not
be acquiring data at the same time as the WFR. Consequently, when any LFDR or WFR data is being
taken, the WBR acqusition is paused.
| Receiver |
Frequency Range |
Sensor |
Time between Snapshots |
Samples per Snapshot |
| WBR |
0 - 80 KHz |
EX |
0.125 second |
2048 |
| MFR |
25 - 12 KHz |
EZ, BZ |
32 seconds |
Other notes:
This trigger produces a maximum data rate of about 131 kbps. If the
Telemetry Mode is S&ER-3, the data is limited to 60,928 bps; but because
the LFDR interrupts the WBR every 32 seconds for about 5.25 seconds, the
effective bitrate is only about 50 kbps for the S&ER-3 mode.
There is a 60-second delay following the execution of this trigger, and
preceding the start of the WBR data acquisition. This allows time for the
MFR to switch antennas and the sounder to finish any pending operation.
This trigger will work with most non-direction-finding triggers, such
as Trigger 28 (Interplanetary Cruise).