Anritsu RA725UA, Инструкция по эксплуатации

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APPENDIX
B
INSTALLATION
B.3
Installation Site
(1) Scanner
The detection ability of shipborne
radar
ch nges greatly with the scanner location. The perfect
mounting location is
as
high above the keel line as possible with
no
obstructions in
all
azimuthal
directions. In practice,
all
ships
are
subject
to
various limitations, and the items
listed
below must
be
considered before selecting the mounting location.
(A) The
maximum
detection distance increases with the height of the scanner installation location.
Install the scanner as high as possible
after
considering the ship construction and scanner
main-
tainability.
(B) If the scanner is installed at the same height as part of a funnel
or
mast, the
radar
pulse
will
be
blocked resulting in a blind spot or ghosting; avoid this
type
of installation location if
at all
possible.
(C) To avoid formation of blind
spots
or ghosting, install
scanner
closer to the ship's bow than any
other
obstacle like a mast or funnel.
If it is impossible to avoid obstacles in the bow direction because of the ship construction, install
the scanner
off
the keel line or elevate the position
so
that a dip angle can be taken.
Method for installing scanner off
keel
line
Displacing the
scanner
to the starboard side
of
the ship moves the blind spot to the port side on
the
radar
display
and
gives a clear view
in
the bow direction. The displacement can be found
from
the
following equations.
Method calculating dip angle
Install the
scanner as
high
as
possible
so
that a sufficient dip angle
(
0
) can
be obtained
between the line of sight between the
scanner
and
obstacle, and a horizontal line. To prevent
blind spots in the medium to long range, the
dip
angle
should
be greater
than
5'
.
Objects
below the line of sight from the
scanner
to the obstacle cannot be detected.
Horizontal line
Line of sight
e
I
(E) Install the scanner where it will not be affected by smoke
of
hot gas
from
the funnel or by heat
Keep the antenna as
far
away as possible from direction-finding equipment and VHF antennas.
(G) Install the scanner within the 10-meter length of the standard connection cable.
If
this is not
40
from spotlights,
etc.
possible, the
maximum
length is m.
(F)
(D)
100