JRC JMR-92 Series Field Service Manual page 18

Use the radar only as a navigation aid.
The final navigation decision must always be made by the operator
him/herself.
Making the final navigation decision based only on the radar display
information may cause accidents such as collisions or running aground.
A malfunction as the screen is disordered or unshown may occur if the power
in the ship is instantaneously interrupted during operation of the radar. In this
case, the power should be turned on again.
Use Target Tracking (TT) function only as a navigation aid. The final
navigation decision must always be made by the operator him/herself.
Making the final navigation decision based only on tracking target information
may cause accidents.
Tracking target information such as vector, target numerical data, and alarms
may contain some errors. Also, targets that are not detected by the radar
cannot be acquired or tracked.
Making the final navigation decision based only on the radar display may
cause accidents such as collisions or running aground.
In the short distance range, do not set the sea clutter suppression function so
that all reflections from the sea are suppressed. This suppresses not only the
echo from waves, etc., but also the echo from floating objects such as ships
or dangerous objects, etc., and obstructs their detection.
When using the sea clutter suppression function, always make the best
suppression setting.
Do not set the rain/snow clutter suppression setting to an excessive level,
because not only the echo from rain or snow but also the echo from floating
objects such as ships or dangerous objects, etc., and obstructs their
detection.
When using the rain/snow clutter suppression function, always make the best
suppression setting.
When setting a guard zone, make sure to properly adjust gain, sea-surface
reflection suppression level, and rain/snow reflection suppression level so
that the optimal target images are always on the radar screen. The guard
zone alarm will not be activated for targets undetected by the radar, and it
may result in accidents such as collisions.
The simulation function is used exclusively for deciding whether or not target
tracking is properly operating. Therefore, never use this function unless you
wish to check target tracking operations.
Note especially that, if this function is used during actual navigation,
simulated targets are displayed and may become confused with other actual
targets. Therefore, never use this function during actual navigation.
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