NorthStar Navigation NorthStar 8000i - Manual (Page 194)

194
Northstar 8000i Operation Manual
42.5 Radar overlay doesn't appear on the chart screen
It's possible that the charted area is outside the maximum range of the radar.
Try zooming in on the charted area.
42.6 Radar shows random or grouped dots
Rain clutter often appears as random dots that can merge into badly-defined
echoes on your Radar screen. The random signals are returned from rain, hail, sleet,
or snow and can result in a confusing display; (see "Change the rain setting" page
134)
42.7 Radar shows random signals in center
Sea clutter usually appears as confusing, random signals in the central area of the
Radar screen. High waves will produce the maximum amount of sea clutter on the
Radar screen.
You can optimize your radar display to reduce the effects of sea clutter; (see
"Change the sea clutter setting" page 133)
42.8 Radar shows different patterns on each sweep
Interference patterns always appear in a different place with each sweep. They can
be randomly scattered bright dots or dotted lines that extend from the centre to
the edge of your Radar screen, often producing a spiral effect. Generally, the
stronger the interference, the wider the interference lines.
You can use the interference rejection feature to reduce interference patterns, and
the width of the interference lines (see "Reduce interference from other radars"
page 134).
42.9 Radar shows multiple echoes off the same object
Multiple echoes off the same object are most likely to occur when you are close to
a large target, and are usually only a temporary nuisance.
42.10 Radar shows arcs and/or shadows
Side lobe patterns often appear as an arc or a broken arc. Shadows are blind spots.
If the radar is installed at a suitable height and in a suitable location on your vessel,
side lobe patterns and shadows caused by obstructions such as funnels or masts
will be minimized.
If you're having problems with these, you may need to relocate your radar. Consult
the Installation Guide for your radar model for advice.