COBHAM SEA TEL 9711IMA-70, Installation Manual

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Introduction 9711IMA-70
1-2
Figure 1 -1 Series 11 TXRX Simplified Block Diagram
1.5. 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 MXP control outputs are connected to an
arbitrator switch panel which then is connected to the below decks equipment. NOTE: The RXIF from EACH
antenna MUST be connected to the RF IN on the rear panel of its respective MXP then RFOUT is connected to the
RXIF input of the Dual Antenna Arbitrator. This 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 the each of the MXPs is connected to the arbitrator panel to control it. The blockage output
terminal of each MXP provides a “blocked” output to the arbitrator its respective antenna is within a blockage zone
programmed into that MXP. When not blocked the SW2 terminal output(s) will signal an “unblocked” state..
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.
1.6. Dual Network Arbitrator
EAR Controlled - ECCN EAR99