Entering an event mark
1.Set the trackball mark where you want to place an event mark (latest event mark).
2.Press an EVENT key. The horizontal range, depth and bear- ing to the event mark appear at the bottom left corner of the screen.
→234: Horizontal range (m) from own ship mark ↓ 19: Present depth (m) to mark
(35): Depth (m) of mark at moment EVENT key is pressed.
B265: Present bearing (degree)
Bottom
|
| (35) |
| B | Stored when |
You observe picture from | EVENT key is | |
| pressed. | |
direction of mark. | A |
|
|
|
Figure 7-11 Event mark description
Plotting an event mark on the display is equivalent to dropping a buoy with an anchoring chain that extends from surface to bot- tom. The buoy is fixed at its present geographical location, but the marker on the display moves to a point where present beam plane intersects the anchor chain of the buoy as the ship moves or the tilt angle is changed. This can be said of other marks as well such as fish mark and trackball mark.
Erasing an event mark
Open the data setting window (sub panel 2) and select DELETE MK. Press appropriate EVENT key to erase mark.