NAVEDTRA 14088 Volume 3 Chapter 2 Flashcards
(32 cards)
When you use subdivisions to assign reference designators to equipment, what is the designator of the (a) largest subdivision and (b) smallest subdivision?
System part
Extremely-low-frequency transmission is primarily directed at which of the following users?
Submarines
The very-low-frequency receive system is designed to receive what types of signals?
FSK and ICW
The AN/FRT-72 (if) transmitter is used to provide (a) how many channels of frequency-division multiplex rtty traffic over (b) what type of fleet broadcast system at (c) what type of power?
(a) Eight (b) multichannel (c) high
HF communications from shore- based transmitters to ships at sea using frequency and space diversity is an example of which of the following types of systems?
Fleet broadcast
Which one of the following equipment would you use to match a transmitter’s output impedance to an antenna’s input impedance?
AN/URA-38
The AN/VRC-80 is not just a vhf transmitter or receiver. What is the name given to a piece of equipment that performs both functions?
Transceiver
During UHF secure voice transmission, the operator uses a secure voice remote phone unit. What is the common term for this unit?
RPU
Which of the following combinations of radio-relay systems provides (a) one-way communications and (b) two-way communications?
Simplex duplex
What term is normally used for microwave transmitter input signal?
Baseband signal
In a microwave transmitter, the linearize couples a portion of the output power back to the klystron. This allows for modulation densities as high as 1200 channels and compensates for what klystron deficiency?
Non-linearity
In a typical microwave receiver, what is the standard intermediate frequency?
70 MHz
Which of the following methods are usually used for microwave communications?
LOS and troposcatter
By which of the following methods can you increase the maximum number of intelligible signals transmitted on a single path?
Multiplexing
Which of the following communications methods involves subdividing a channel into smaller segments of equal size and placing a signal in each subchannel?
FDM
What requirements does SAS satisfy?
Nonsecure voice communications, secure voice communications, and voice signal switching
How many crypto and plain subsystems are used within SAS?
Five
One mode of teletypewriter operation is the synchronous mode. What other mode is used for basic teletypewriter operation?
Asynchronous
What is the name of the five-unit code that includes mark and space signals and is used in teletypewriter operation?
Baudot
Which of the following problems is reduced by not using start and stop signals in the synchronous teletypewriter mode?
Distorted signal
Which of the following terms accually pertains only to modulation rate?
Baud
In neutral tty operation, current flow and no current flow represent the mark and space conditions. In polar tty operation what is the condition of the line current?
It is always present
What device is used to change tty dc pulses into mark and space signals to modulate the transmitter carrier wave?
Keyer
After the tty signal is received, what device(s) must be used to change the signal back to dc pulses?
Converter and receiver
