Simrad CA42, Руководство пользователя

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CA42/50/52 Glossary of terms Appendix A
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NU – North-Up In this mode, targets are displayed at their measured distances
in true direction from your boat. North being at the top of the display. In the
North-Up mode, you must be interfaced with an electronic compass for proper
operation.
Off-Center mode - lets you position the origin own ship to any point on the
screen within 66% of the radius of the display (the center 2/3 of the display).
The Off-Center mode permits the operator to obtain a greater view in the
direction of interest.
PLOT function – will require that a heading sensor (Gyro or Compass) is
connected to the CAXX. If so, then you can plot the actual cursor position on the
radar display by pressing the [PLOT] key from the radar display, and thereby
save the position in the WP-list as a waypoint i.e. you can give the plotted
waypoint a new name/number, symbol, color, etc.
PPI center – Plan Position Indicator.
RAIN CLUTTER Control – also known as Fast Time Constant (FTC), is used
to reduce large clutter masses caused by rain or snow and allow targets masked
by this clutter to be seen on the radar display. This control differentiates the
multitude of small radar returns from rain, effectively reducing or eliminating the
rain clutter and allowing the operator to observe larger vessel traffic within the
rain clutter. It has the effect of only displaying the leading edge of large echoes
and will tend to effect the smaller echoes only slightly. This can be of
great advantage on shorter ranges to distinguish between two very close echoes
on the same bearing which may otherwise merge and appear as one echo.
Relative Motion Land, buoys and fixed objects move past own ship. In the
North-Up mode, you must be interfaced with an electronic compass for proper
operation.
SEA CLUTTER Control – also known as the Sensitivity Time Control (STC),
is normally used on the shorter ranges to suppress the effects of sea clutter close
to own ship by reducing the nearby gain level. It can effectively reduce the
strength of the mass of random echoes received from nearby sea clutter for up to
approx. 3 to 5 nm depending on wave and sea conditions. STC control is set to
reduce the strength of these echoes such that the clutter appears only as
intermittent small dots, yet small targets can still be distinguished.
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On short range scales, the setting of the sea clutter control should never be