Edgetech 2000-TVD, User Hardware Manual

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4. Click the Bottom Track tab. This tab is shown in F
IGURE
3-8 .
Figure 3-8: Lower Control Panel, Bottom Track Tab—DISCOVER 2000-C
5. On the Bottom Track tab make the required settings to track the bottom and note the towfish
altitude in the Altitude display.
6. Lower the towfish such that its altitude is 10–15% of the range selection.
7.
Increase the survey vessel speed to the desired survey speed and adjust the amount of cable out
such that the altitude of the towfish remains at 10–15% of the range selection.
8. If a pressure sensor is installed, verify that the Pressure display indication is correct.
9. Secure the tow cable to the survey vessel.
10.
Begin recording data.
3.10 Towfish Recovery
To recover the towfish:
1. In the DISCOVER 2000-C Dual Frequency Side Scan Main window, click the Transmit tab and clear
the High Sonar On and Low Sonar On check boxes. This tab is shown in
F
IGURE
3-5 .
The side scan transducers should stop transmitting.
2. In the DISCOVER Sub-Bottom Main window, choose Sonar On from the Sonar menu. When the
sonar is off, no check mark should be present next to the menu item.
The sub-bottom transducer should stop transmitting.
3. Slowly pull in the tow cable until the towfish is just below the surface.
4. Slow the survey vessel speed to under two knots. However, if practical, the survey vessel should
be put in neutral while the towfish is brought on board.
5. Retrieve the towfish from the water and carefully lower it on deck.
6. Disconnect the tow cable from the tow cable connector.
7. Install the dummy plug on the tow cable connector.