Furuno BB FAR28x7 - Manual (Page 46)

1. RADAR OPERATION
1-20
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.
Heading Line
North Marker
True motion mode
Automatic resetting of own ship mark in true motion mode
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(a) True motion
is selected
(b) Own ship has reached a
point 75% of display radius
(c) Own ship is automatically
reset to 75% of radius