How To Enter Own Ship Speed; How To Automatically Acquire Targets; Echo-Referenced Speed Input - Furuno FAR-2218 Operator's Manual

Note 1: For successful acquisition, the target should be within 24 NM (or 32 NM, de-
pending on initial setting) from own ship and not obscured by sea or rain clutter.
Note 2: You are alerted when the capacity of manual acquisition is 95% and 100%.
These alerts are "TT TARGET95%(MAN)" and "TT TARGET FULL(MAN)". If the capac-
ity is 100% you cannot acquire more targets. Cancel tracking of non-threatening targets
if you wish to acquire additional targets manually.
Note 3: When a target being tracked nears another target being tracked, the targets
may be "swapped". When two targets acquired either automatically or manually come
close to each other, one of the two may become a lost target. If this occurs, manual re-
acquisition of the lost target may be necessary after the two have separated.
Note 4: You can reuse a target number. This is useful when you acquire the "wrong"
target. Drag and drop the symbol onto the correct target.
3.5.2

How to automatically acquire targets

Targets are automatically acquired when the TT mode is set to other than [MANUAL
100] and a target enters the acquisition zone (see section 3.16). The maximum track-
ing distance (24 NM or 32 NM) is set at installation.
3.6

How to Enter Own Ship Speed

The TT requires own ship's speed and heading data. The speed can be STW, SOG
or echo-referenced speed (based on 3 max. stationary objects). Manual input is also
possible. For automatic or manual input, see section 1.12. For echo-referenced speed
input follow the procedure below.
3.6.1

Echo-referenced speed input

The use of echo-referenced speed is recommended when:
• The speed log is not operating properly or not connected to the radar.
• The vessel has no device (doppler sonar, speed log, etc.) that can measure ship's
bow-stern, port-starboard movement.
If you select echo-referenced speed, the TT calculates own ship's speed relative to a
fixed reference target. The number of targets may be R1, R2 or R3. When a plural of
objects are selected, the mean value is used, for stabilization and speed.
1. Right-click the operational display area to show the [CURSOR MENU].
2. Select [REF MARK]. The cursor is highlighted to indicate that the reference mark
function is active.
3. Place the cursor on a fixed echo (such as an island, etc.) at a range of 0.1 to 24
NM from own ship, to be used as a reference, then left-click. The cursor changes
from the highlighted cross to a circle with dashed lines, indicating that the refer-
ence location is now set. See section 3.9 for more information on TT symbols and
their attributes.
At acquisition
The dashed lines of the reference point change to a solid line over time, as shown
in the figure above.
Stable tracking
3. TARGET TRACKING (TT)
3-5