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Transducer depth | This option specifies how far below the surface of the water |
| the transducer is mounted. The number is added to all depths |
| measured by the 491 so they will refer to depth from the |
| surface, not from the transducer. This value should have been |
| set correctly during installation and should not be changed. |
Changing the depth units
Changing the temperature graph’s units and scale
This option only appears on the screen if a temperature sensor is connected.
Number of special waypoints
You can change the depth units to feet, meters, or fathoms:
1.Press the CURSOR PAD up or down to highlight the
DEPTH UNITS option.
2.Press EDIT.
3.Press the CURSOR PAD left or right to highlight the desired units. Press ACCEPT.
You can change the highest and lowest water temperatures that will be displayed on the temperature graph:
1.Press the CURSOR PAD up or down to highlight the line containing the temperature scale.
2.Press EDIT.
3.Press the CURSOR PAD left or right to highlight °C or °F, as desired, then press ACCEPT.
4.To change the endpoints of the scale, press EDIT DATA.
5.Enter the lower temperature limit using the KEYPAD.
6.Press the CURSOR PAD to the right to highlight the upper limit and enter its value on the KEYPAD.
7.Press ACCEPT.
In the 961/962, the echo sounder can be set to store waypoints automatically at the following location:
•where fish are detected by the fish alarm
•where the water temperature passes preset limits
•where fish or other echoes are marked by the user
These waypoints are automatically given names such as *FISH##*, where ## is a waypoint sequence number that increases to a preset limit. When this limit is reached, the
Page 24 | 491 Echo Sounder Operations Manual |