Trigger 52 Description

Sequence: C37, C38, C39, C40, etc.
Trigger 52 ( SKR WBR cyclic turn-on, without compression)

This trigger is designed to overlay HF Wideband Receiver data, at 325 KHz, on top of a direction-finding trigger, such as 80 (Antenna Calibration), or 94 (SKR/Aurora Outside Source). This mode is designed to provide a hirate mode for analyzing SKR fine structure. 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. Data acquisition continues for all receivers, with the exception of the dust detector and the HFR normal analysis mode. In addition to selecting the 80-KHz band, with the HF mode selected at 325 KHz, this trigger turns off compression of the WBR data, and forces the snapshot length to 2048 samples. These things are necessary to prevent the low-frequency WFR and the LFDR data acquisition from blocking WBR data acquisition. Additionally, the HFR is run in millisecond mode, at 325 KHz.

Receiver Frequency Range Sensor Time between Snapshots Snapshot Length
WBR 0 - 80 KHz HF(325KHz) 0.125 second 2048
HFR 310-340 KHz band EX about 2.25 seconds 2048


Other notes:

This trigger produces a maximum data rate of about 139 kbps. If the Telemetry Mode is S&ER-3, the data is limited to 60,928 bps.

There is a 60-second delay following the execution of this trigger, and preceding the start of the WBR data acquisition. In sequences C37 and C38, this was only a 35-second delay. This allows time for the HFR to finish any analysis which might be in progress. There will be a gap in the HFR normal analysis while it is in this mode, so this trigger should only be used briefly.