Electronics Technician Vol 3 Comm Systems

Front 1

What type of equipment is used to coordinate the activities of fleet units by linking them with each other and shore stations?

Back 1

Radio

Front 2

Radio is the transmission and reception of electronic impulses or signals through space by means of what type of waves?

Back 2

Electromagnetic

Front 3

Who is ultimately responsible for safety?

Back 3

Everyone

Front 4

What are the basic requirements of a communication system?

Back 4

Transmitter and Receiver

Front 5

AN/UCC-1, AN/URA-17, and CV-2460 are examples of what type of shipboard equipment?

Back 5

Terminal

Front 6

For Efficient transmissions, which of the following frequency bands requires high power and long antennas?

Back 6

ELF, VLF, and LF

Front 7

Which of the following frequency bands has limited Naval use?

Back 7

MF

Front 8

What does the abbreviation "los" commonly mean?

Back 8

Line of Sight

Front 9

The SHF band is used extensively in what of communications?

Back 9

Microwave

Front 10

The emission class of an RF transmitter is based on what characteristic?

Back 10

Modulation

Front 11

An FM signal should remain constant in (what) characteristic and change in only (what )characteristic?

Back 11

Amplitude and frequency

Front 12

What type of modulation is especially suited for use in time-division multiplexing?

Back 12

Pulse

Front 13

For modern communication needs, CW is not a preferred method, why is this true?

Back 13

CW is slow.

Front 14

In an FM transmitter the audio signal shifts the carrier frequency in what network?

Back 14

Audio-shift

Front 15

In a SSB transmitter the carrier is removed to concentrate the power in the sidebands.

Back 15

True

Front 16

Which of the 4 receiver functions involves extraction of the modulation from the RF signals?

Back 16

Detection

Front 17

Which of the 4 receiver characteristics require compromise because of bandpass requirements?

Back 17

Selectivity and Fidelity

Front 18

What term is used to describe receiver amplification?

Back 18

Gain

Front 19

The term dBm is based on what standard reference level?

Back 19

1 watt

Front 20

Normal power out is 100 watts. During PMS, you discover that power out has dropped by 3dB. What is the new power out?

Back 20

50 Watts

Front 21

How many Radio set controls can be paralleled to one transmitter / receiver group?

Back 21

Four

Front 22

To Transfer control of switched circuits to another transmitter or receiver switchboard, you should use what switch position?

Back 22

X

Front 23

Which of the following terms is used for a machine that operates as a single-phased transformer?

Back 23

Synchro

Front 24

When you use subdivisions to assign reference designators to equipment, what is the designator of the (a) largest subdivision and the (b) smallest subdivision?

Back 24

System Set

Front 25

ELF transmission is primarily directed at which of the users?

Back 25

Submarines

Front 26

The VLF receive system is designed to receive what type of signals?

Back 26

FSK and ICW

Front 27

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?

Back 27

Eight Multichannel High

Front 28

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?

Back 28

Fleet Broadcast

Front 29

Which of the following equipment would you use to match a transmitters output impedance to an antennas input impedance?

Back 29

AN/URA-38

Front 30

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?

Back 30

Transceiver

Front 31

During UHF secure voice transmission, the operator uses a secure voice remote phone unit. What is the common term for this unit?

Back 31

RPU

Front 32

Which of the following of radio-relay systems provides (a) one-way communications and (b) two-way communications?

Back 32

Simplex Duplex

Front 33

What term is normally used for microwave transmitter input signal?

Back 33

Baseband Signal

Front 34

In a microwave transmitter, the linearize couples a portion of the outlet power back to the klystron. This allows for modulations densities as high as 1200 channels and compensates for what klystron deficiency?

Back 34

Oscillations

Front 35

In a typical microwave receiver what is the standard intermediate frequency?

Back 35

70 MHz

Front 36

Which of the following methods are usually used for microwave communications?

Back 36

Los and troposcatter

Front 37

By which of the following methods can you increase the maximum number of intelligible signals transmitted on a single path?

Back 37

Modulation

Front 38

Which of the following communications methods involves subdividing a channel into smaller segments of equal size and placing a signal in each subchannel?

Back 38

TDM

Front 39

What does SAS satisfy?

Back 39

Nonsecure Voice Communications, Secure Voice communications, Voice switching signals.

Front 40

How many crypto and plain subsystems are used within the SAS.

Back 40

Five

Front 41

One mode of teletypewriter operation is the synchronous mode. What is the other mode used for the basic teletypewriter operation?

Back 41

Asynchronous

Front 42

What is the name of the five unit code that includes marks and space signals and is used in teletypewriter operation?

Back 42

Baud

Front 43

Which of the following problems is reduced by not using start and stop signals in the synchronous teletypewriter mode?

Back 43

Distorted Signal

Front 44

Which of the following terms actually pertains only to modulation rate?

Back 44

Baud

Front 45

In neutral TTY operation current flow and no current flow represent the mark and space conditions. In polor TTY operation what is the condition of the line current?

Back 45

It is always positive

Front 46

What device is used to change TTY dc pulses into mark and space signals to modulate the transmitter carrier wave?

Back 46

Keyer

Front 47

After the TTY signal is received, what device must be used to change the signal back to dc pulses?

Back 47

converter and receiver

Front 48

The Navy's two basic RATT systems are AFTS and RFCS. What is the RFCS system commonly called?

Back 48

FSK

Front 49

What device provides looping current for the TTY?

Back 49

A solid state power supply

Front 50

What is/are used to interconnect all the TTY equipment in any configuration needed?

Back 50

TTY Panel

Front 51

Which of the following methods is/are used to reduce fading or interference in long-range communications?

Back 51

Frequency and Space Diversity

Front 52

What type of frequency diversity is used for multichannel broadcasts?

Back 52

Tone

Front 53

During unpatching, pulling which plug from its TTY panel jack first will produce a dangerous dc voltage on the exposed plug?

Back 53

Set

Front 54

How many rotary switch positions will you find on a remote transmitter control unit?

Back 54

Three

Front 55

In AFTS, to what does the term "half-duplex" refer?

Back 55

Send Only, Receive only, and Send or Receive.