GMDSS. FCC Test 38

The Inmarsat telephone and telex communications channel usage scheme is:

One ship per telephone channel and many ships per telex channel.
Many ships on the same telex analog channel frequency and many ships on the same TDM telephone channel.
One ship per channel whether telephone or telex.
One ship per analog telephone channel and one ship per telex analog channel frequency.

What is the purpose of compandors?

To keep the Inmarsat-A/B antenna pointing at the desired satellite, regardless of the ship's position and course, it has an input from the vessel's:

What is an Inmarsat 'Subscriber Number'?

This is the Inmarsat number that is assigned to a unit for incoming calls.
This number is used for receiving news and other optional services in FleetNET.
This is the vessel's Inmarsat registration number for accounting authority purposes.
This identifies the vessel's selective calling (selcall) number.

What is an MRN?

How is a signal radiated from an Inmarsat-A system's antenna?

It is radiated in an omni-directional pattern.
It is radiated in an omni-directional pattern that can be reversed by the Operator to attain directional beaming to an alternate satellite.
It is a highly focused directional signal that must be beamed at the desired satellite.
It is usually radiated in an omni-directional pattern, but an optional feature allows it to be directional for use when the vessel is on the fringe of the satellite's footprint.

Which of the following statements concerning Inmarsat geostationary satellites is true?

They are in an equatorial orbit to provide true global coverage.
They provide coverage to vessels in nearly all of the world's navigable waters.
Vessels sailing in equatorial waters are able to use only one satellite whereas other vessels are able to choose between at least two satellites.
They are in a low-earth polar orbit to provide true global coverage.

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