NAVEDTRA 14189A NEETS MODULE 17 CH. 1 Flashcards
Communications Principles
What are the two types of electrical communication?
Radio and wire
What is the main advantage of radiotelegraph communications?
Reliability
Why is radiotelophone one of the most useful methods of military communications?
It is direct, convenient and easy to use.
What are the disadvantages of radiotelephone communications?
Static, enemy interference or a high local noise level.
What is the main use of a radio teletypewriter?
High speed automatic communications across ocean areas.
What is facsimile?
The process used to transmit photographs, charts and other graphic information electronically.
A system is subdivided into what levels?
Set, group, unit, assembly, subassembly and part.
The majority of VLF transmitters are used for what purpose?
Fleet communications or navigation.
Today the Navy uses LF communications as a segment of what operational system?
Fleet multichannel broadcast system.
Why does the Navy only use the upper and lower ends of MF band?
Due to the commercial broadcast band (AM).
What are the four general types of communications services in the HF band?
Point to point, ship to shore, ground to air and fleet broadcast.
A message transmitted on several frequencies at the same time is an example of what type of transmission?
Frequency diversity
Physically separating receive antennas is an example of what technique?
Space diversity
Physically separating receive antennas is an example of what technique?
Space diversity
When using frequencies above 30MHz, you are normally limited to using what range?
Line of sight
