1. Features

2. Headframe

3. Sensors

4. Electronics

5. Picture

• Frontal area of this design has been minimized to reduce avoidance and bow wave effect.

• Stable in all axis. Pitch is typically -0 to +15 deg., depending on towing speed, and can be adjusted with either the adjustable tow point or the adjustable planing fins.

• Depth is consistent to within .5 meters. Currents have minimal impact on either depth holding or towing attitude.

• Deployment is not effected by wind direction, current direction or ship heading.

• Tow speed range of 1 to 5 knots, inclusive of winch speed.

• Operations with either a conductive tow cable (real-time telemetry) or non-conductive steel cable (self-contained mode) are supported.

• Deck software provides real-time data of all converted sensor readouts on screen, and permits net drops on command (conductive tow cable required). Net opening criteria for self-contained operations is specified before deployment.

Headframe

• Depth: 1000 meter operating, 2000 meter crush

• Speed: 1 to 5 knots

• Nets: 10, including first "open-to-depth"

• Net Size: .5m x .5m mouth opening

• Net Mesh: Mesh and cod end collar size specified by user. Filtration area of min 4:1 recommended.

Sensors

• CTD - Applied Micro Systems STD 12+ is standard. Seabird SBE19 optional. Others available on request. Resolutions and accuracy dependent on CTD sensors specified by purchaser. The CTD is normally modified to be powered from system battery pack.

• Net Count switch verifies net openings and triggers data file time stamp.

• Pitch Sensor range of +/- 45 deg., used to calculate effective mouth area.

• Flow Meters (2) measuring outside flow (speed) and inside flow (swept volume). Calculated differential between flows indicates net clogging.

• Many other sensors can be accommodated, as well as altimeters and light packages. We would be pleased to quote on your specific requirements.

• Main pressure case contains CPU, 128 Kb memory, interfaces for CTD, flowmeters, pitch and net drop sensors, and stepper motor drivers. Included are two spare 8 bit channels and one slot for an additional board.

• Battery pressure case contains Nicad battery pack ( 6 and 12 volt taps), and charger control cards. Battery life is typically 48 hrs, depending on temperature and optional instrumentation, based on six deployments per day of two hrs duration.

• Shipboard module provides communications loop to RS-232; serial port to computer interface; and battery charger.

• Deck software runs on any IBM compatible computer. Real time operation is supported, as well as programming of operations in self-contained mode. A discrete data set is saved for each net opened. ASCII data can be saved as either raw data files or in real engineering units. Post processing conversion of raw data is supported. Diagnostics are included.

• Tow cable can be either shielded co-ax or multi-conductor cable. Modems are used for co-ax while serial loop is used for multi-conductor cables. Non-conducting wire tow cable limits operations to self-contained mode.