1-D-19: Antennas
1-19D1:
What are the antenna requirements of a VHF telephony coast, maritime utility or ship station?
The shore or on-board antenna must be vertically polarized.
The antenna array must be type-accepted for 30-200 MHz operation by the FCC.
The horizontally-polarized antenna must be positioned so as not to cause excessive interference to other stations.
The antenna must be capable of being energized by an output in excess of 100 watts.
1-19D2:
What is the antenna requirement of a radiotelephone installation aboard a passenger vessel?
The antenna must be vertically polarized and as non-directional and efficient as is practicable for the transmission and reception of ground waves over seawater.
The antenna must be located a minimum of 15 meters from the radiotelegraph antenna.
An emergency reserve antenna system must be provided for communications on 156.800 MHz.
All antennas must be tested and the operational results logged at least once during each voyage.
1-19D3:
What is the most common type of antenna for GMDSS VHF?
None of the above.
Horizontally polarized circular antenna.
Long wire antenna.
Both of the above.
1-19D4:
What is the purpose of the antenna tuner?
It alters the electrical characteristics of the antenna to match the frequency in use.
It physically alters the length of the antenna to match the frequency in use.
It makes the antenna look like a half-wave antenna at the frequency in use.
None of the above.
1-19D5:
What advantage does a vertical whip have over a long wire?
It radiates equally well in all directions.
It radiates more signal fore and aft.
It radiates a strong signal vertically.
None of the above.
1-19D6:
A vertical whip antenna has a radiation pattern best described by?
A circle.
A figure eight.
A cardioid.
An ellipse.
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