Neets Mod 17 Ch 1 & 2

Front 1

1-1. For naval communications to be effective, all involved must be top performers. Reliable, secure, and timely
receiving and transmitting of information is the goal. Which of the following requirement standards are used to determine whether or not this goal has been met?
1. Wartime
2. Peacetime
3. Cold war less 10 percent
4. Nuclear war less 25 percent

Back 1

Wartime

Front 2

1-2. What are the two types of electrical communications?
1. Radio and wire
2. Television and wire
3. Telegraph and radio
4. Television and radio

Back 2

Radio and wire

Front 3

1-3. Which of the following terms includes intelligence produced by wire, radio,
visual means, oral means or
electromagnetic systems?
1. Telecommunications
2. Radiotelegraph
3. Electrolysis
4. Photocopy

Back 3

Telecommunications

Front 4

1-4. Radiotelegraph (cw) is valuable when communicating to, from, and among widely separated naval units. What is the main advantage of the cw mode?
1. Cost
2. Speed
3. Security
4. Reliability

Back 4

Reliability

Front 5

1-5. Tactical communications is usually considered as line-of-sight. What maximum distance is normally within the line-of-sight range?
1. 5 miles
2. 25 miles
3. 50 miles
4. 250 miles

Back 5

25 miles

Front 6

1-6. You want to transmit high-speed automatic page or tape copy across an ocean area. Which of the following
methods should you choose?
1. Facsimile
2. Radiotelegraph
3. Radiotelephone
4. Radioteletypewriter

Back 6

Radioteletypewriter

Front 7

1-7. What method is normally used to transmit graphs electronically?
1. Facsimile
2. Radio teletypewriter
3. Frequency-shift keying
4. Audio-frequency-tone shifting

Back 7

Facsimile

Front 8

1-8. When you use subdivisions to assign
reference designators to equipment, what is the designator of (a) the largest and (b) the smallest?
1. (a) System (b) set
2. (a) Set (b) unit
3. (a) Unit (b) assembly
4. (a) System (b) part

Back 8

(a) Unit (b) assembly

Front 9

1-9. When using the reference designator 1A6A4J6, what level does the number 1
refer to?
1. Subassembly
2. Assembly
3. Group
4. Unit

Back 9

Unit

Front 10

1-10. What is the total number of frequency bands the military is currently using for communications?
1. 5
2. 7
3. 9
4. 11

Back 10

9

Front 11

1-11. Extremely low-frequency transmissions are primarily directed at which of the
following users?
1. Shore installations
2. Surface ships
3. Submarines
4. Aircraft

Back 11

Submarines

Front 12

1-12. Vlf transmitters are used primarily for which of the following purposes?
1. Navigation and fleet communications
2. Frequency standards and time signals
3. Astronomy and oscillator calibration
4. Aircraft control and space vehicle tracking

Back 12

Navigation and fleet communications

Front 13

1-13. Navy use of the low-frequency band is mainly for which, if any, of the following broadcasts?
1. Ship to shore
2. Fleet multichannel
3. Space vehicle telemetry
4. None of the above

Back 13

Fleet multichannel

Front 14

1-14. For which of the following reasons does the Navy use only the upper and lower ends of the mf band?
1. They are the most reliable
2. They produce the best propagation
3. The commercial fm band occupies the middle
4. The commercial AM band occupies the middle

Back 14

The commercial fm band occupies the middle

Front 15

1-15. Hf communications over long-distance trunks, or links between fixed terminals
are examples of which of the following types of systems?
1. Fleet broadcast
2. Point-to-point
3. Ground-to-air
4. Ship-to-shore

Back 15

Point-to-point

Front 16

1-16. Sending a message on several frequencies at once is an example of which of the following transmission types?
1. Time-diversity
2. Phase-diversity
3. Distance-diversity
4. Frequency-diversity

Back 16

Frequency-diversity

Front 17

1-17. What type of diversity uses physically separated transmit or receive antennas to improve communications?
1. Time
2. Phase
3. Space
4. Frequency

Back 17

Space

Front 18

1-18. Normally the transmission range of vhf is
limited to line of sight. What technique is used to increase this range?
1. Tropospheric scatter
2. Atmospheric diversity
3. Ionospheric maneuvering
4. Each of the above

Back 18

Tropospheric scatter

Front 19

1-19. A complex of links make up a major communications system. The naval
communications system is further broken down into what two groups?
1. Strategic and local
2. World-wide and local
3. Strategic and tactical
4. Tactical and world-wide

Back 19

Strategic and tactical

Front 20

1-20. Communications links have many modes of operation. One terminal in a link has
its equipment setup in simplex. The other terminal is using two channels or
frequencies in a configuration that allows
sending and receiving of different messages at the same time. These two
terminals working together make up what mode of operation?
1. Full duplex
2. Half duplex
3. Quasiduplex
4. Semiduplex

Back 20

Semiduplex

Front 21

1-21. What communications link mode of operation provides telecommunications
capability between stations at the same time in both directions?
1. Half duplex
2. Semiduplex
3. Broadcast
4. Duplex

Back 21

Duplex

Front 22

1-22. Aid in restoring downed fleet communications channels is furnished on a not-to-interfere basis by which of the following networks?
1. AUTOSEVOCOM
2. NORATS
3. HICOM
4. DSSCS

Back 22

HICOM

Front 23

1-23. Which of the following switched networks extends tactical voice to shorebased
operational commands?
1. NORATS
2. AUTOVON
3. AUTODIN
4. AUTOSEVOCOM

Back 23

NORATS

Front 24

1-24. Of the following transmitter types, which are used for basic communications?
1. Cw, AM, fm, and ssb
2. Fsk, cw, AM, and tty
3. Cw, ssb, voice and fm
4. Voice, tty, fsk, and AM

Back 24

Cw, AM, fm, and ssb

Front 25

1-25. Cw transmissions have narrow bandwidths and a high degree of intelligibility under severe noise conditions. What is the primary Navy use for cw?
1. Radioteletypewriter
2. Radiotelegraphy
3. Facsimile
4. Voice

Back 25

Radiotelegraphy

Front 26

1-26. A cw transmitter must contain which of the following components?
1. A traveling-wave tube
2. A demodulator
3. A combiner
4. A keyer

Back 26

A keyer

Front 27

1-27. In a cw transmitter, a buffer stage performs which of the following functions?
1. Current divider
2. Voltage divider
3. Current amplifier
4. Voltage amplifier

Back 27

Voltage amplifier

Front 28

1-28. There are differences between low- and high-power transmitters. The main
difference is the high power transmitter contains a larger number of which of the
following types of amplifiers?
1. Oscillator
2. Final power
3. Intermediate power
4. Intermediate frequency

Back 28

Intermediate power

Front 29

1-29. In an AM transmitter, audio frequencies are converted into corresponding
electrical energy by which of the following components?
1. An oscillator
2. A microphone
3. A modulator
4. A headset

Back 29

A microphone

Front 30

1-30. In an fm transmitter, a varicap performs which of the following functions?
1. It amplifies the outgoing signal
2. It varies the oscillator frequency
3. It demodulates the outgoing signal
4. It multiplies the oscillator frequency

Back 30

It varies the oscillator frequency

Front 31

1-31. If an oscillator has a fundamental frequency of 3,550 megahertz, what is
the frequency of the third harmonic?
1. 5,325 megahertz
2. 7,100 megahertz
3. 9,875 megahertz
4. 10,650 megahertz

Back 31

10,650 megahertz

Front 32

1-32. If the fundamental frequency of an rf carrier is 1,000 kilohertz, what is the
frequency of the fourth subharmonic?
1. 500 kilohertz
2. 333 kilohertz
3. 250 kilohertz
4. 200 kilohertz

Back 32

250 kilohertz

Front 33

1-33. Oscillator output frequencies are raised to usable values by frequency
multipliers. To raise an oscillatorm frequency from 20 megahertz to 120 megahertz, what combination of frequency multipliers would be used?
1. Two doublers
2. A doubler and a tripler
3. A doubler and a quadruplet
4. A tripler and a quadruplet

Back 33

A doubler and a tripler

Front 34

1-34. When an AM signal leaves the antenna of a transmitter, which of the following frequency components does the signal
contain?
1. The carrier
2. The upper sideband
3. The lower sideband
4. All of the above

Back 34

All of the above

Front 35

In a single-sideband transmitter, selection of the desired sideband and suppression of the other is done by which of the
following components?
1. Mixer
2. Filter
3. Detector
4. Oscillator

Back 35

Filter

Front 36

When compared to a conventional AM signal, an ssb signal provides which of
the following advantages?
1. Improved frequency stability
2. Increased receiver gain
3. Reduced distortion
4. Reduced bandwidth

Back 36

Reduced bandwidth

Front 37

1-37. For ship-to-shore teletypewriter circuits,
which of the following types of multiplexing is/are used?
1. Time and/or phase
2. Time and/or frequency
3. Phase and/or modulation
4. Frequency and/or modulation

Back 37

Time and/or frequency

Front 38

1-38. Operators of transmitters and receivers
use a circuit to coordinate the service of messages and to make frequency changes. What is the name of this
circuit?
1. Order-wire circuit
2. Documentation circuit
3. Synchronization circuit
4. Operator-eyes-only circuit

Back 38

Order-wire circuit

Front 39

1-39. A transmitted electromagnetic wave
enters an antenna, induces a voltage into it, and passes that voltage to a receiver.
What is this chain of events called?
1. Reproduction
2. Selection
3. Detection
4. Reception

Back 39

Reception

Front 40

1-40. When a receiver picks one frequency out from all other frequencies, it's
performing which of the following basic functions?
1. Selection
2. Reception
3. Detection
4. Reproduction

Back 40

Selection

Front 41

1-41. When a receiver separates the audio
frequencies from the radio-frequency carrier it is performing which of the
following basic functions?
1. Reception
2. Selection
3. Detection
4. Reproduction

Back 41

Detection

Front 42

1-42. The receiver action of converting electrical energy to a usable format, such as sound, is an example of which of the following basic functions?
1. Reception
2. Selection
3. Detection
4. Reproduction

Back 42

Reproduction

Front 43

1-43. Which of the following measurements provides an indication of the ability of a
receiver to reproduce weak signals?
1. Bandwidth
2. Sensitivity
3. Selectivity
4. Frequency response

Back 43

Sensitivity

Front 44

1-44. Overall sensitivity of a receiver is limited by which of the following factors?
1. Noise
2. Bandwidth
3. Output power
4. Frequency response

Back 44

Noise

Front 45

1-45. How is a receiver's ability to reject unwanted signals and receive desired
signals determined?
1. Noise
2. Fidelity
3. Selectivity
4. Sensitivity

Back 45

Selectivity

Front 46

1-46. When high fidelity is your prime consideration you should select a receiver that has been designed with which of the following features?
1. High gain
2. High output power
3. Broadband frequency selection circuits
4. Narrowband frequency selection circuits

Back 46

Broadband frequency selection circuits

Front 47

1-47. The IF frequency in a receiver is produced by which of the following methods?
1. Modulation
2. Heterodyning
3. Frequency synthesis
4. Frequency multiplication

Back 47

Heterodyning

Front 48

1-48. The process of heterodyning takes place
in which of the following receiver circuits?
1. Mixer
2. Comparator
3. Oscillator
4. Second IF amplifier

Back 48

Mixer

Front 49

1-49. Of the following frequencies, which one is a typical value of IF for AM
communications receivers?
1. 455 kilohertz
2. 554 kilohertz
3. 455 megahertz
4. 554 megahertz

Back 49

455 kilohertz

Front 50

1-50. Two or more circuits within a receiver are varied by a single control through the use of which of the following processes?
1. Ganged tuning
2. Frequency synthesis
3. Automatic gain control
4. Automatic frequency control

Back 50

Ganged tuning

Front 51

1-51. There are electrical differences between AM and fm receivers. An fm receiver
contains which of the following circuits?
1. Comparator
2. Discriminator
3. Limiter
4. Both 2 and 3 above

Back 51

Both 2 and 3 above

Front 52

1-52. An fm signal has which of the following
characteristics when compared to an AM signal?
1. More noise
2. Less static
3. A higher power output
4. A lower operating frequency

Back 52

Less static

Front 53

1-53. Ssb transmissions have which of the following characteristics when compared
to AM transmissions?
1. Wide bandpass frequencies
2. Concentrated power
3. Less modulation
4. High fidelity

Back 53

Concentrated power

Front 54

1-54. Single sideband receivers use a special
oscillator. The output of that oscillator is fed directly to the detector circuit. What type of oscillator is used?
1. Local
2. High frequency
3. Variable frequency
4. Carrier reinsertion

Back 54

Carrier reinsertion

Front 55

1-55. A transmitter has a suppressed carrier frequency of 4 megahertz and is radiating only an upper sideband signal. When the
intelligence is a 1-kilohertz tone, which of the following sideband frequencies will be transmitted?
1. 3,999 kilohertz
2. 4,000 kilohertz
3. 4,001 kilohertz
4. Both 2 and 3 above

Back 55

4,001 kilohertz

Front 56

1-56. Manual gain lets you adjust a receiver for maximum sensitivity and amplify weak
input signals. Which of the following internal sections of the receiver are varied by this control?
1. Oscillator
2. Audio frequency
3. Radio frequency
4. Intermediate frequency

Back 56

Radio frequency

Front 57

1-57. Manual volume control of a receiver internally varies the input to which of the following circuits?
1. Detector
2. Audio amplifier
3. Frequency converter
4. Radio frequency amplifier

Back 57

Audio amplifier

Front 58

1-58. Changes in receiver input strength due to changing atmospheric conditions is described by which of the following
terms?
1. Gain
2. Fading
3. Ducting
4. Trapping

Back 58

Fading

Front 59

1-59. The rf amplifier connected to your receiving antenna has a voltage gain of
240. When the antenna is receiving a signal of 8 microvolts, what will be the
maximum output voltage of the rf amplifier?
1. 1.92 millivolts
2. 2.91 microvolts
3. 30 microvolts
4. 33 millivolts

Back 59

1.92 millivolts

Front 60

1-62. To automatically compensate for input signal strength variations within a
receiver, which of the following types of circuits are added?
1. Afc
2. Nfc
3. Agc
4. Nsu

Back 60

Agc

Front 61

1-63. AgC circuitry within a receiver uses a portion of which of the following
detector voltage components as a feedback signal to preceding stages?
1. Dc
2. Ac
3. IF
4. Audio

Back 61

Dc

Front 62

1-64. Which of the following types of agc voltage drives an amplifier toward cutoff?
1. Saturation
2. Delayed
3. Reverse
4. Forward

Back 62

Reverse

Front 63

1-65. What is the purpose of the squelch circuit in a receiver?
1. To attenuate very strong signals in order to prevent their overdriving the
remaining stages in the receiver
2. To suppress receiver noise output when no input signal is being received
3. To suppress the electronic "whine" of the rf amplification stage
4. To reject signals of other than the desired frequency should the receiver drift off frequency

Back 63

To suppress receiver noise output when no input signal is being received

Front 64

1-66. How does a receiver accomplish the squelch function?
1. By proportional blocking of the rf amplifier stage output
2. By blocking the detector or audio amplifier when there is no signal
3. By switching an inductive/capacitive
filter into the output of the last rf amplifier
4. By switching in a matched-frequency stage which passes matching frequencies and rejects all others

Back 64

By blocking the detector or audio amplifier when there is no signal

Front 65

1-67. A quartz crystal filter is used in a communications receiver to improve which of the following characteristics?
1. Fidelity
2. Sensitivity
3. Selectivity
4. Reproduction

Back 65

Selectivity

Front 66

1-68. When the wiper of R1 is placed in the full treble position, which of the
following actions occur?
1. Bass response is improved
2. High frequency shunting is reduced
3. Higher frequencies are shunted to
ground
4. The capacitor and resistor are placed
in parallel

Back 66

High frequency shunting is reduced

Front 67

1-69. Automatic frequency control circuits are used in a receiver for which of the
following purposes?
1. To adjust IF amplifier gain
2. To correct for oscillator frequency drift
3. To extend the frequency range of the receiver
4. To automatically tune the receiver to the desired frequency

Back 67

To correct for oscillator frequency drift

Front 68

1-71. A change in oscillator frequency will change which of the following input
relationships between the sawtooth reference voltage and the incoming signal?
1. Phase
2. Voltage
3. Current
4. Amplitude

Back 68

Phase

Front 69

1-72. How is the long term stability and accuracy required of modern
communications receivers attained?
1. Through the use of a single, crystalcontrolled
oscillator, as the local
oscillator
2. Through the use of an electroncoupled oscillator, as the local oscillator
3. Through a process of automatic frequency control
4. Through a process known as
frequency synthesis

Back 69

Through a process known as
frequency synthesis

Front 70

1-73. When using the frequency synthesis process, a signal of the desired accuracy and stability is produced by which, if any, of the following methods?
1. Automatic frequency control, that is, by sensing the difference between the
oscillator frequency and the desired frequency and automatically compensating for this difference
2. Using a crystal-controlled oscillator to produce a stable high frequency, and through the process of frequency division selecting a subharmonic of this frequency as the desired
frequency
3. The heterodyning and selection of frequencies which are not harmonically related to each other
4. None of the above

Back 70

The heterodyning and selection of frequencies which are not harmonically related to each other

Front 71

1-74. Permanent magnet speakers respond quite well to which of the following
audio frequency ranges?
1. Low
2. High
3. Mid band
4. Each of the above

Back 71

Low

Front 72

1-75. For which of the following reasons do most standard Navy headphones respond poorly to low frequencies?
1. Small diaphragm size
2. Diaphragm inflexibility
3. Both 1 and 2 above
4. Input signal filtering

Back 72

Both 1 and 2 above