Sea Tel 4009-9 BROADBAND-AT-SEA, Руководство по установке

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4009-9 Installation Manual Setup – Blockage & RF Radiation Hazard Zones
11-4
EXAMPLE 3 - One blockage Zone: A ship has a Sea Tel
antenna mounted on the center line of the ship. A mast is
forward and an engine exhaust stack is aft. In this example
the Stack does NOT block the satellite, only the mast
forward does. In this example zone 1 is caused by the mast,
zone 2, 3 and 4 are not needed:
ZONE 1 begins (AZ LIMIT 1) at 352 degrees Relative
and ends (AZ LIMIT 2) at 8 degrees Relative.
Multiply these Relative positions by 10. Enter AZ
LIMIT 1 value of 3520 and AZ LIMIT 2 value of 0080.
In this case the mast height only causes blockage
up to an elevation of 52 degrees, so we set EL LIMIT
12 to 0520. If the antenna is between these two AZ
Limit points but the elevation is greater than 52
degrees, the antenna will no longer be blocked.
ZONE 2 is not needed. Enter AZ LIMIT 3 value of
0000 and AZ LIMIT 4 value of 0000. Set EL LIMIT
34 to 0000.
ZONE 3 is not needed. Enter AZ LIMIT 5 value of
0000 and AZ LIMIT 6 value of 0000. Set EL LIMIT 56 to 0000.
ZONE 4 is not needed. Enter AZ LIMIT 7 value of 0000 and AZ LIMIT 8 value of 0000. Set EL LIMIT 78 to
0000. If your ACU software includes 5 volt polarization you will not see these AZ & EL LIMIT parameters.
EXAMPLE 4 - Overlaid Blockage Zones: A ship has a
Sea Tel antenna mounted on the center line of the ship.
A mast mounted on top of a deckhouse (like the picture
below) is forward and an engine exhaust stack, also on a
deckhouse, is aft. These two blockage areas have wide
azimuth blockage at lower elevations and then a
narrower azimuth area of blockage extends up to a
higher value of elevation.
ZONE 1 begins (AZ LIMIT 1) at 334 degrees
Relative and ends (AZ LIMIT 2) at 026 degrees
Relative. Multiply these Relative positions by 10.
Enter AZ LIMIT 1 value of 3340 and AZ LIMIT 2
value of 0260. In this case the mast height only
causes blockage up to an elevation of 40
degrees, so we set EL LIMIT 12 to 0400. If the
antenna is between these two AZ Limit points
but the elevation is greater than 40 degrees, the
antenna will no longer be blocked.
ZONE 2 begins (AZ LIMIT 3) at 352 degrees
Relative and ends (AZ LIMIT 4) at 008 degrees
Relative. Multiply these Relative positions by 10.
Enter AZ LIMIT 3 value of 3520 and AZ LIMIT 4
value of 0080. In this case the mast height only
causes blockage up to an elevation of 70
degrees, so we set EL LIMIT 34 to 0700. If the
antenna is between these two AZ Limit points
but the elevation is greater than 70 degrees, the antenna will no longer be blocked.