NAVEDTRA 14189A Flashcards
What year was the first official naval radio message sent from ship to shore?
1899
What year was the first radiotelephone used between ships?
1916
In what year were the first superheterodyne receivers installed in the fleet?
1931
In what year were the first successful radio teletypewriter transmissions between ships completed?
1944
In what year did the first successful use of radiophoto (facsimile) occur?
1945
What refers to communications over a distance and includes any transmission, emission, or reception of signs, signals, writings, images, or sounds?
Telecommunications
What is the most important method the Navy has of communicating between widely separated forces?
Radio
What was the first means of radio communications that had military and commercial importance?
Radiotelegraphy
Line-of-sight characteristics limit the usual range of radiotelephone from how many miles?
20-25
The Navy uses radio teletypewriter (rtty) mainly for high-speed automatic communications across ocean areas and has a normal speed of operation of how many words per minute?
100
What is the process used to transmit photographs, charts, and other graphic information electronically?
Facsimile (fax)
What is a combination of sets, units, assemblies, subassemblies, and parts joined together to perform a specific operational function or several functions?
System
What consists of a unit or units and the assemblies, subassemblies, and parts connected or associated together to perform a specific function?
Set
What is a collection of units, assemblies, subassemblies, and parts?
Group
What is an assembly or any combination of parts, subassemblies, and assemblies mounted together?
Unit
What is a number of parts or subassemblies, or any combination thereof, joined together to perform a specific function?
Assembly
What is one component or two or more components joined together?
Part
What is the frequency range for the extremely high frequency (EHF) band?
30 GHz-300GHz
What is the frequency range for the super high frequency (SHF) band?
3GHz-30GHz
What is the frequency range for the ultra high frequency (UHF) band?
300MHz-3GHz
What is the frequency range for the very high frequency (VHF) band?
30MHz-300MHz
What is the frequency range for the high frequency (HF) band?
3MHz-30MHz
What is the frequency range for the medium frequency (MF) band?
300KHz-3MHz
What is the frequency range for the low frequency (LF) band?
30 KHz-300KHz
What is the frequency range for the very low frequency (VLF) band?
3KHz-30KHz
What is the frequency range for the extremely low frequency (ELF) band?
Up to 300Hz
What band has the ability to penetrate ocean depths to several hundred feet with little signal loss?
ELF
What type of transmission is normally considered a broadcast, that is, one-way transmission, no reply required?
VLF
What systems are established to communicate over long-distance trunks or links between fixed terminals?
Point-to-point
What is normally a message circuit between two points that are both switching centers or individual message distribution points?
Trunk
What is a transmitter-receiver system connecting two locations?
Link
Frequencies above what are not normally refracted by the atmosphere and ground-wave range is minimal?
30 megahertz
The naval communications system is broken down into what groups?
Strategic and tactical
What type of communications are usually limited to a specific area of operations and are used to direct or report the movement of specific forces?
Tactical
What mode is a method of operation in which telecommunications between stations takes place simultaneously in both directions using two separate frequencies?
Full-Duplex (fdx)
What is the type of operation in which one station transmits information on one or more channels directed to more than one station and/or unit?
Broadcast (bc)
Message traffic is normally sent to the fleet by three methods: broadcast, intercept, and what else?
Receipt
What combines into a single system all the elements that make up the naval communications system and the Army and Air Force equivalent?
DCS
What offers rapid, direct interconnection of DOD and certain other government installations through worldwide telephone exchanges?
DCS AUTOVON
What provides authorized users with a means for exchanging classified information over communications security (COMSEC) circuitry or over other approved circuitry?
AUTOSEVOCOM
Daily capacity of the AUTODIN system is about how many average-length messages?
Five million
What was established for the purpose of integrating the critical intelligence communications (CRITICOMM) and the special intelligence communications (SPINTCOMM) networks into a single automated communications network?
DSSCS
What network provides a voice link between the Chief of Naval Operations (CNO) and all subordinate commands ashore, afloat, and airborne?
HICOM
What meets our need for a connection between Navy tactical voice systems of the operating forces and the various fixed telephone services ashore?
NORATS
What is the principle use of the continuous wave?
Radiotelegraphy
A cw transmitter requires four essential components. These are a generator, amplified, keyer, and what else?
Antenna
What is power the product of?
Current and Voltage
What refers to a sine wave quantity (for example, an oscillator output) that has a frequency that is a submultiple of the frequency of some other sine wave quantity it helped make?
Subharmonic
What are special power amplifiers that multiply the input frequency?
Frequency multipliers
What is the elimination of the undesired portions of the signal?
Suppression