Sea Tel 6012-33, Nstallation Manual

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Configuring The Satellite Modem Interface. 6012-33 Installation Manual
11-5
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
Compatibl
e 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
ComTech 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
STM N/A On Low 3 Off Low Off
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.