Sea Tel 5012-33, Installation Manual

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5012-33 Installation Manual Series 12 Ku-Band System Configuration(s)
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1.4. Dual Antenna Configuration
Sometimes, due to very large blockage conditions, you may need to install a dual antenna configuration to provide
uninterrupted services. Two full antenna systems are installed and the ACU control outputs are connected to an
arbitrator switch panel which then is connected to the below decks equipment. The connection scheme is required for
MXP “A” to be able to control Antenna “A” (and ONLY Antenna “A”) AND MXP “B” to be able to control Antenna “B”
(and ONLY Antenna “B”).
You will program the blockage zone(s) for each of the two antennas (refer to Setup – Blockage Zones). The blockage
output from each MXP is fed to the arbitrator. The blockage output is a transistor “short” to ground when the antenna
is within a programmed blockage zone and is an “open” when not blocked.
When one antenna is blocked, its blockage output will command the arbitrator panel to switch services to the modem
from that antenna to the other antenna. The arbitrator panel provides a logic latch to prevent excess switching when
the ship heading is yawing, therefore, causing if the antenna to be repeatedly blocked – unblocked – blocked.