NorthStar 958 Operator's Manual page 139

Changing the
rotation
958 Operator's Manual, Rev. A
If there's no radar overlay on the chart, you scale the chart and
radar separately; zooming in on the chart, for example, has no
affect on the radar. If the CONTROL key indicates RADAR,
you're zooming the radar; if it indicates CHART, you're
zooming the chart.
However, if the chart has a radar overlay and you zoom in on
the chart, radar changes to match. Changing the chart's scale
changes the radar; and changing the radar's scale changes the
chart, even if the chart isn't visible.
To change the radar's rotation, press the ROTATE key
repeatedly until it indicates the rotation you want; you have
the same options as for a CHART screen (see "Rotating the
chart" starting on page 49).
The rotation of the chart and the rotation of the radar interact
under certain circumstances, as described in the table below.
Assume that the chart and radar are both north-up at the start.
If the CONTROL key indicates RADAR, you're rotating the
radar; if it indicates CHART, you're rotating the chart.
CHART
If the
screen's in ...
Browse mode The chart can't rotate; but if
you change the
key to
mode automatically switches
to vessel (see below)
Vessel mode Chart and radar both rotate
together, so if you change
the radar to leg-up, the chart
automatically changes to
match (and vice versa)
Chapter 10 - Understanding Radar Functions
And the radar image is ...
Overlaid on the chart
CONTROL
RADAR
, the chart's
Not overlaid
The chart can't rotate but the
radar can rotate; so if you
change the radar to leg-up,
the chart doesn't change (it
stays north-up)
Chart and radar both rotate
but separately; so if you
change the radar to leg-up,
the chart doesn't change
(and vice versa)
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