COBHAM Sea Tel 9711-56 IMA C Band, Руководство по установке

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Sea Tel 9711-56 IMA Configuring The Satellite Modem Interface.
11-5
EAR Controlled - ECCN EAR99
numerous predefined conditions are met. In most cases, these are conditions that
ultimately determine that the system is not accurately pointed to the desired satellite.
However there are some conditions where this may not be true, as is the case of the antenna
being pointed at a pre-defined “Radiation Hazard Zone”, which discussed in detail within
another chapter of this manual, is programmed in as a Blockage Zone, thus the name Block
Output.
There may be an area on board the vessel in which crew and/or guests may be in the direct
path of the terminals transmission to the satellite and might possibly be harmed by long
term exposure to the microwave signal. This sector would be described as a blockage zone
so that the transmissions from the antenna would cease when pointed in that area.
Similarly a mast or other structure on the ship, directly in the beam path of the transmission,
which would prevent transmitted signal from reaching the satellite and cause reflections
which may degrade the signal or even be harmful to the antenna. These obstructions would
also be described as a blockage zones. This similar in concept to “sector blanking” a radar
array.
11.1.4.6. Modem I/O – Block Output – 12V Pull Up
Use: The Modem I/O Block Output 12V Pull Up selection defines whether or not use a built-
in 12VDC Pull up resistor for the hard lined wire input for Blockage output (TX Mute).
If your modem requires a continuity based input (Short to ground is Low, and Open is High)
this selection must be set to OFF. For all voltage based modem inputs, it MUST be set to
ON.
Selection Type: Mutually Exclusive Radio Buttons
Options : 12V Pull Up OFF or ON.
Notes: Modem Type “Custom” must have been selected to allow changes to this setting.
Example: Your modem requires a high, voltage based, input to mute the modem. You
would set Polarity to Hi and 12V Pull Up to ON.
If your modem required a low, continuity based, input to mute the modem. You would set
Polarity to Low and 12V Pull Up to OFF.
11.2. Quick Reference: Common Modem Lock & Mute Settings
Modem
Type Compatible
ABS Mode Lock
Input -
Lock Lock
Input –
Polarity Lock
Input –
Voltage Lock
Input -
12V Pull
Up Block
Output -
Polarity Block
Output -
12V Pull
Up
iDirect OpenAMIP* On Low 12 Off Hi On
ComTec
h ROAM* On Low 12 On Low On
Gilat N/A On Low 12 Off Low Off
Hughes N/A On Hi 12 Off Hi On
Viasat N/A On Low 12 Off Low Off
Custom CLI* On As
Required As
Required As
Required As
Required As
Required
* NOTE : When interfacing ABS (via Ethernet connection) Lock input and Block Output selections have no operational impact.