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

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Setup – Blockage & RF Radiation Hazard Zones 4009-9 Installation Manual
11-3
LIMIT 34 to 0120. If the antenna is between these two AZ Limit points but the elevation is greater than
12 degrees, the antenna will no longer be blocked.
ZONE 3 begins (AZ LIMIT 5) at 156 degrees Relative and ends (AZ LIMIT 6) at 172 degrees Relative.
Multiply these Relative positions by 10. Enter AZ LIMIT 5 value of 1560 and AZ LIMIT 6 value of 1720. In
this case the stack antenna height only causes blockage up to an elevation of 36 degrees, so we set EL
LIMIT 56 to 0360. If the antenna is between these two AZ Limit points but the elevation is greater than
36 degrees, the antenna will no longer be blocked.
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 2 - Three blockage Zones, Dual Antenna
configuration: A ship has 2 Sea Tel antennas, “Antenna
A” mounted on the port side and “Antenna B” mounted
on the starboard side. Antenna A is designated as the
master antenna and its zones would be set as in example
1 above. The mast forward, Antenna A to port and the
engine exhaust stack aft form the three zones where
satellite signal is blocked from Antenna B. The SW2
logic output from Antenna A (ACU A) and Antenna B
(ACU B) are used to control a “Dual Antenna Arbitrator”,
which will route satellite signal from the un-blocked
antenna to the other below decks equipment. If both
antennas are tracking the same satellite, they will not
both be blocked at the same time. The logic output will
switch to provide satellite signal to the below decks
equipment from Antenna A when it is not blocked and
will switch to provide satellite signal from Antenna B
whenever Antenna A is blocked. The switches will not
change state if both antennas are blocked, or if both are
on satellite.
Antenna A is the same as the previous example and its ACU would be set to those AZ LIMIT values.
Antenna B ACU would be set to:
In this example Antenna B zone 1 is caused by the stack, zone 2 is from Antenna A, zone 3 is from the mast and
zone 4 is not needed.
ZONE 1 begins (AZ LIMIT 1) at 188 degrees Relative and ends (AZ LIMIT 2) at 204 degrees Relative.
Multiply these Relative positions by 10. Enter AZ LIMIT 1 value of 1880 and AZ LIMIT 2 value of 2040. In
this case the stack height only causes blockage up to an elevation of 42 degrees, so we set EL LIMIT 12 to
0420. If the antenna is between these two AZ Limit points but the elevation is greater than 42 degrees,
the antenna will no longer be blocked.
ZONE 2 begins (AZ LIMIT 3) at 254 degrees Relative and ends (AZ LIMIT 4) at 278 degrees Relative.
Multiply these Relative positions by 10. Enter AZ LIMIT 3 value of 2540 and AZ LIMIT 4 value of 2780. In
this case the Antenna B height only causes blockage up to an elevation of 12 degrees, so we set EL LIMIT
34 to 0120. If the antenna is between these two AZ Limit points but the elevation is greater than 12
degrees, the antenna will no longer be blocked.
ZONE 3 begins (AZ LIMIT 5) at 342 degrees Relative and ends (AZ LIMIT 6) at 348 degrees Relative.
Multiply these Relative positions by 10. Enter AZ LIMIT 5 value of 3420 and AZ LIMIT 6 value of 3480. In
this case the mast height only causes blockage up to an elevation of 41 degrees, so we set EL LIMIT 56 to
0410. If the antenna is between these two AZ Limit points but the elevation is greater than 12 degrees,
the antenna will no longer be blocked.
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.