Raytheon Anschuetz GmbH High Seas Products MTX5 ユーザーズマニュアル
Chapter 1: Overview
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Selecting the best location for the scanner unit requires careful consideration of
the following points, to ensure reliable and trouble free operation:
the following points, to ensure reliable and trouble free operation:
Note: In order to minimise potential interference to other systems on board
ship (EMC), it is advisable to mount the scanner on a part of the boat that is
insulated from the ship’s battery negative. If you cannot do this, and encounter
problems, you can fit insulating bushes between the scanner and its mounting
bracket.
ship (EMC), it is advisable to mount the scanner on a part of the boat that is
insulated from the ship’s battery negative. If you cannot do this, and encounter
problems, you can fit insulating bushes between the scanner and its mounting
bracket.
• Height: The scanner unit should normally be mounted as high as practical
above the waterline, for three reasons:
- Safety -the scanner should above head height of personnel. This avoids
mechanical danger and electromagnetic contact, particularly with the
eyes.
eyes.
- Radar operates at the line-of-sight, so a high mounting position gives
better long range performance.
- Surrounding large objects, in the same horizontal plane, can interfere with
the radar signal and cause blind areas or shadow sectors and false targets
on the radar screen (see below).
on the radar screen (see below).
However, do not mount the scanner so high that it is affected by the pitching
and rolling of the vessel. In addition, you may need to lower the scanner to
avoid creating a shadow sector.
and rolling of the vessel. In addition, you may need to lower the scanner to
avoid creating a shadow sector.
• Access: The scanner unit site should be easily accessible to allow
maintenance to be carried out safely.
• Magnetic compass: Mount the scannner unit at least 1 m away from a
magnetic compass.
• Cable run: The maximum length of cable between the display unit and the
scanner unit should not normally exceed 20 m (60 ft) for radome scanners, or
15 m (45 ft) for open array scanners. If you need to use a longer cable power
cable lengths must be considered, refer to Section 1.4 Cable Runs.
15 m (45 ft) for open array scanners. If you need to use a longer cable power
cable lengths must be considered, refer to Section 1.4 Cable Runs.
• Shadow sectors and false echoes: Mount the scanner away from large
structures or equipment, such as the fly bridge, large engine stacks,
searchlights, horns, or masts. It is particularly important to avoid shadow
sectors near the bow. Raising or even lowering the scanner may help to
reduce these effects.
searchlights, horns, or masts. It is particularly important to avoid shadow
sectors near the bow. Raising or even lowering the scanner may help to
reduce these effects.
In shadow areas beyond the obstruction there will be a reduction of the beam
intensity, although not necessarily a complete cut-off; there will be a blind
sector if the subtended angle is more than a few degrees.
intensity, although not necessarily a complete cut-off; there will be a blind
sector if the subtended angle is more than a few degrees.
In some shadow sectors the beam intensity may not be sufficient to obtain an
echo from a very small object, even at close range, despite the fact that a
large vessel can be detected at a much greater range. For this reason the
echo from a very small object, even at close range, despite the fact that a
large vessel can be detected at a much greater range. For this reason the
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