Datasheet for the Sonardyne AST 7904 Acoustic Switch Transponder, an emergency system for AUVs and ROVs operating in the LF band with ranges up to 10,000…
The Type 7904 Acoustic Switch Transponder (AST) is designed to provide Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) with an emergency system that operates independently of all other systems. Reception of a sequence of acoustic commands causes a contact closure within the AST, which can be used to release a weight and cause the vehicle to rise to the surface.
| Depth Rating | 3,000 Metres |
|---|---|
| Operating Frequency | LF (7.5kHz-15kHz) |
| Transceiver Frequency | 13.26kHz |
| Transceiver Pulse Length | 10ms |
| Transceiver Source Level (Alkaline) | 190dB |
| Transceiver Source Level (Lithium) | 184dB |
| Receiver Sensitivity | <95dB |
| Quiescent Life (Alkaline) | 9 months |
| Quiescent Life (Lithium) | 24 months |
| Shelf Life (Alkaline) | 24 months |
| Shelf Life (Lithium) | 84 months |
| Weight in Air | 12kg |
| Weight in Water | 6kg |
The acoustic parameters are set to allow ranges up to 10,000 metres in suitable environmental conditions.
The contact remains closed for 4 seconds and then opens again.
It is compatible with LF versions of Sonardyne transceivers such as the PAN, RovNav and LCU.