Lowrance HDS Live Operator's Manual page 139

The North up orientation is not available if no heading source is
connected to the radar. If heading data is lost, the system will
automatically switch to Head-up orientation.
Course up
In Course up mode, the top of the bearing scale indicates the ship's
true course measured from north at the time Course up was
activated. When the ship turns the bearing scale remains fixed,
while the heading line rotates with the ship's yawing and course
change.
The Course up orientation is reset by re-selecting the Course up
mode.
Offsetting the PPI center
You can set the antenna position origin to different location on the
radar PPI. The options described in the next sections are available.
Ú Note:
Offsetting the PPI center is allowed only in Relative
motion.
PPI center: Center
You return the antenna center to PPI center by using the offset
option in the View menu.
Ú Note:
The bearing scale is according to the Consistent
Common Reference Point (CCRP), while the offset sets the radar
antenna position on the PPI. The maximum off-centering
allowed is 75% of the radius at the current range. This may
result in the CCRP being outside of the bearing scale. In such
cases the measurements are still taken by the CCRP and the
bearing scale is compressed accordingly.
Radar| HDS Live Operator Manual
PPI center: Look Ahead PPI Center: Offset
139