| Physical Attributes | One Ti pressure housing holding data-logger, WHOI-designed clock-board, and rechargeable backup battery for the clock. Three Ti pressure housings hold primary lithium batteries. Two Ti pressure housings each hold independent acoustic releases. Air weight with/without anchor is 1,300 lbs/1,234 lbs. Dimensions are 53” x 42” x 33.5” (high to top of bail). OBS can stack two-high. |
| Data Logger | Nanometrics Pegasus OBS 4-channel data logger 24-bit A/D. Sample-rate options are 1,000, 500, 250, 200, 100, 50, 40, 20, 10, 5, and 1 Hz. Data are recorded on a high-reliability 128 GByte eMMC. |
| Clock | Continuously powered Seascan clock with power-cycled Teledyne Chip-Scale Atomic Clock (CSAC) to measure Seascan frequency at operator-specified intervals. |
| Sensors | Seismometer options are a Nanometrics T-360 OBS, Nanometrics T-120 OBS, or a Nanometrics Trillium Compact OBS, all in Ti housings. Seismometer is deployed behind a shield to reduce environmental noise. Pressure sensor is an SIO Differential Pressure Gauge (DPG). |
| Recording Duration | Lithium battery pack for ~24 months recording at 100 Hz. Separate keep-alive battery for clock. |
| Operation | Operated in closed-housing mode i.e. programming of acquisition parameters, offloading of data, clock setting, etc, all done through penetrators or Bluetooth. Pressure tubes carry an electronic vacuum gauge to ensure tubes are well sealed prior to deployment. |
