Smiths Kelvin Hughes Nucleus 3 5000 Series, Системный справочник

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RAIN (FTC)
225 The rain control reduces clutter from rain, snow and
hail. The rain facility also provides attenuation of sea
clutter, though RACON responses are likely to be
suppressed. The rain level can be set from 0 (minimum) to 9
(maximum) with a typical operational level of between 2 and
4.
226 The rain setting is adjusted to preserve small targets. It
is often beneficial to reduce the Gain level to optimise
target detection in high precipitation.
227 The use of S-Band radar is advantageous in very high
precipitation conditions.
NOTE:
(1) The rain facility also improves short range
discrimination.
(2) When not in use the rain control should always be set
to 0.
MAPS, ROUTES & WAYPOINT PO SI TIONING
228 Maps, routes and waypoints can be positioned in one
of two projections: Great Circle or Rhumb Line. The
operator must ensure that the projection mode is set as
required prior to using this facility. Map facilities are
described in paragraphs 145 to 158.
229
Refer to Chapter 5 - Commissioning, for levels and
default setting information.
Great Cir cle
230
Typically used for maps, as points of fixed Latitude and
longitude remain coincident with the radar returns, but
straight lines joining two points are only useful as a means of
associating those points.
Rhumb Line
231 Typically used for routes between waypoints, as the
straight line in this projection may represent the rhumb
line that the ship is sailing, hence an indication of cross track
error may be read directly from the radar return.
CURVED EBL
232
An electronic bearing line that graphically displays the
rate of turn/radius of turn that the vessel will take to
effect a new course. The turn shown will include the ship’s
forwarding distance. (Refer to paragraph 128).
WHEEL OVER POINT
233
Causes an active curved EBL to become sea
stabilised. By activating the wheel over point as soon
as the autopilot has been commanded to steer to a new
course, it becomes possible to monitor the vessels progress
around the turn by comparing it to the curved EBL. The WOP
box is highlighted with a red border when active, and
automatically deactivates when the gyro heading comes
within 3 degrees of the curved EBL bearing. It can be
deactivated at any time by pressing the WOP function again.
PAR AL LEL IN DEX LINES
234 These are Ownship stabilised lines which extend
across the width of the PPI. The angle to, and distance
from Ownship is adjustable. By setting PI lines to channel
boundaries, it is possible to get a view of Ownship position
compared to the channel boundaries.
July 03 1.30 Amdt. 5
KH 2020
Chap 1