Deck 2: Amplitude Modulation

Question 1

Which of the following would be a reason why double-sideband AM is still so widely used?
A.SSB systems more complex
B.Power-savings
C.Noise advantages
D.Effective utilization of available frequency spectrum

Answer 1

SSB systems more complex

Question 2

Which of the following is an example of an application where double-sideband,full-carrier (DSBFC)AM would be used?
A.Marine and citizens band (CB) radios
B.Military services
C.Aircraft-to-tower communication
D.Amateur (ham) radios

Answer 2

Aircraft-to-tower communication

Question 3

What type of sideband is used for analog television video transmissions?
A.Amplitude-compandored
B.Vestigial
C.ISB transmission
D.Pilot carrier

Answer 3

Vestigial

Question 4

What was ultimately developed in the search for a communications technique that was immune to noise?
A.FM
B.AM transmitter
C.Bandwidth
D.Frequency spectrum

Question 5

The ___________ produces side frequencies or sidebands,one on each side of the carrier.
A.phasors' angular velocity
B.vector sum
C.pure sine wave
D.modulated AM signal

Question 6

A transmitter modulator circuit combines carrier and intelligence signals that are widely separated in _____________.
A.frequency
B.amplitude
C.harmonics
D.voltage

Question 7

What is the carrier's job in the modulator?
A.Calculation of the modulation index
B.Frequency translation
C.Aliasing
D.Transmitting

Question 8

Conventional AM transmitters are rated in terms of _________________.
A.bandwidth
B.amplitude modulating signals
C.modulated waveforms
D.carrier power output

Question 9

All information contained at the output of the AM modulator is contained within the __________.
A.balanced modulators
B.bandwidth
C.transmitter
D.sidebands

Question 10

Mixing (modulation)is achieved when signals are applied to a(n)____________.
A.nonlinear device
B.sideband
C.linear device
D.intermod

Question 11

The rate of phasor rotation is called angular _____________.
A.velocity
B.sidebands
C.sine waves
D.frequencies

Question 12

Which of the following is the term that defines when two signals at different frequencies are combined in a nonlinear device?
A.Aliasing
B.Mixing
C.Foldover distortion
D.Fluctuating

Question 13

In an AM transmission,why does the carrier contain no information?
A.It is always changing.
B.It is related to sine-wave frequency.
C.It never changes.
D.The signal is a low frequency compared to the carrier.

Question 14

What law is represented when current flow through a device increases in direct proportion to voltage?
A.Hartley's law
B.Plank's law
C.Ohm's law
D.Henry's law

Question 15

Transmission of a modulated signal with both the carrier and one sideband removed produces what type of signal?
A.SSB
B.AM
C.FM
D.HF

Question 16

Which of the following is the most important advantage of SSB systems?
A.Reducing the noise present at receiver by half.
B.All information is contained within varying-amplitude sidebands.
C.More effective utilization of the available frequency spectrum.
D.The carrier amplitude and frequency always remain constant.

Question 17

What situation occurs if the modulating signal amplitude continues to increase?
A.Maximum amplitude
B.Overmodulation
C.Sideband splatter
D.Odd harmonics

Question 18

Why are SSB receivers more difficult to tune than conventional AM receivers?
A.Need for carrier reinsertion
B.Bandwidth required by SSB cut in half
C.Complete signal cancellation may result
D.Overcrowded high-frequency spectrum

Question 19

P1P1_1.75The increase and decrease in the AM waveform's amplitude is caused by the frequency difference in the _______________. P1P1_E
A.intelligence signals
B.bandwidth
C.side frequencies
D.sine waves

Question 20

A phasor rotating at a constant rate will generate a(n)____________.
A.sine wave
B.angular velocity
C.waveform
D.amplitude

Question 21

What is the gap called that produces distortion and results in the transmission of frequencies outside a station's normal allocated range?
A.Odd harmonics
B.Sideband splatter
C.Square waves
D.Intermod

Question 22

Undesired frequencies in close proximity to desired ones,such as a difference frequency appearing within the baseband,are difficult if not impossible to identify and remove after they have been created.What does this occurrence represent?
A.Modulation envelope
B.Pure sine-wave intelligence
C.Foldover distortion
D.Modulating signal frequency

Question 23

Noise is directly proportional to _____________.
A.total power output
B.peak envelope power
C.available frequency spectrum
D.bandwidth

Question 24

What is the term for undesired mixing?
A.Intermod
B.Peak envelope power
C.ISB transmission
D.Amplitude

Question 25

Three characteristics of a sine wave carrier are amplitude,frequency,and ____________.
A.phase
B.intelligence
C.voltage
D.bandwidth