Modern Electronic Communication by Gary Miller Chapter 4 with Answers

Chapter 4: Single-Sideband Communications


1. An SSB signal with a maximum level of 200 V p-p into a 50 load results in a PEP  rating of
 
    a. 200 W
    b. 50 W
    c. 100 W
    d. 800 W

2. State the chief advantage(s) of a standard SSB system.
 
    a. Maximum signal range with minimum transmitted power
    b. Easy carrier reinsertion
    c. Elimination of carrier interference
    d. a and c

3. The noise advantage of SSB over AM is
 
    a. 3–5 dB
    b. 5–7 dB
    c. 8–10 dB
    d. 10–12 dB

4. What is the difference between a balanced modulator and a regular modulator?

    a. There is no carrier produced in the output of a balanced modulator.
    b. In a balanced modulator, there is 180º phase shift between the upper and lower sidebands.
    c. In a balanced modulator, only one sideband is produced.
    d. In a balanced modulator, harmonics of the sidebands are suppressed.

5. In a balanced-ring modulator, the carrier suppression is accomplished by

    a. A dual-gate FET having symmetry
    b. Center-tapped transformers causing canceling magnetic fields
    c. The nonlinearity of the diodes that are used
    d. Symmetrical differential amplifier stages

6.Which cannot be used successfully to convert DSB-SC to SSB?

    a. Crystal filter
    b. Ceramic filter
    c. Mechanical filter
    d. Tank circuit


7. Another term for ripple amplitude for a ceramic filter is
 
    a. The shape factor
    b. The peak-to-valley ratio
    c. The insertion loss
    d. The quality factor

8. Which of the following is not an advantage of the phase method over the filter method in producing SSB?
 
    a. The design of the 90º phase-shift network for the intelligence frequencies is  simple.
    b. Lower intelligence frequencies can be economically used, because a high-Q filter is not necessary.
    c. Intermediate balanced modulators are not necessary, because high-Q filters are not needed.
    d. It is easier to switch from one sideband to the other.

9. Once an SSB signal has been generated, it must be amplified by

    a. A nonlinear amplifier to conserve bandwidth
    b. A nonlinear amplifier to conserve energy
    c. A linear amplifier to conserve bandwidth
    d. A linear amplifier to avoid distortion

10. The advantages provided by carrier elimination in SSB do not apply to  transmission of

    a. Code
    b. Music
    c. Noise
    d. All the above

11. Provide the approximate "outside-of-passband" attenuation of a Butterworth filter.

    a. 3-dB slope per octave
    b. 3-dB slope per decade
    c. 6-dB slope per octave
    d. 6-dB slope per decade

12. An SSB receiver recreates the original intelligence signal by

    a. Mixing the USB with LSB signals and filtering out the resulting different  frequencies
    b. Filtering out the difference between either sideband and the internally  generated carrier signal
    c. Filtering out the harmonics of the received sideband signal frequencies
    d. Amplifying the dc term produced by mixing action

13. Common types of balanced modulators include
 
    a. Ring modulator
    b. Phase modulator
    c. Lattice modulator
    d. All the above


14. Describe the oscilloscope waveform of an SSB transmitter's balanced modulator if  it exhibits carrier
      leakthrough.
 
    a. Trapezoidal wave
    b. Sinewave
    c. FM wave
    d. AM wave

15. The two-tone test is used to
 
    a. Test carrier suppression
    b. Test filter ripple
    c. Test amplifier linearity
    d. None of the above



Answers:


C
D
D
A
B
D
B
A
D
B
C
B
A
D
C

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