Furuno FA Manual page 45

True motion mode
Own ship and other moving objects move in accordance with their true courses
and speed. In ground stabilized TM, all fixed targets, such as landmasses,
appear as stationary echoes. In the sea stabilized TM without set and drift inputs,
the landmass can move on the screen. Note that true motion is not available on
the 72 nm (non-IMO type only) or 96 nm range scale. If COG and SOG (both
over the ground) are not available on TM mode, enter the set (tide direction) and
drift (tide speed) manually referring to the Tide Table.
When own ship reaches a point corresponding to 50% of the radius of the
display, own ship position is automatically reset to a point of 75% radius opposite
to the extension of the heading line passing through the display center. You may
also reset the own ship symbol manually by pressing the [CU/TM RESET] key,
or roll the trackball to choose the CU/TM RESET box at the bottom right corner
of the display and then push the left button.
If the heading sensor fails, the mode is changed to the head-up and the north
marker disappears. The HDG readout shows ***.*° and the message HDG SIG
MISSING appears in red at the lower-right corner of the screen.
Automatic resetting of own ship mark in true motion mode
Heading
340 350 000 010
020
330 030
line
320
310
300
290
280
270
260
250
240
230
220
210
150
200 160
190 180 170
(a) True motion
is selected
North Marker
True motion mode
North
marker
330
320
040
050 310
060 300
070 290
080 280
090 270
100 260
250
110
120 240
230
130
140 220
210
200
(b) Own ship has reached a
point 75% of display radius
Heading Line
340 350 000 010
020
030
040
050
060
070
080
090
100
110
120
130
140
150
160
190 180 170
1. RADAR OPERATION
340 350 000 010
020
330 030
320
040
310 050
300
290
280
270
260
250
240
230
130
220 140
210
150
200 160
190 180 170
(c) Own ship is automatically
reset to 75% of radius
060
070
080
090
100
110
120
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