Modern Electronic Communication by Gary Miller Chapter 3 with Answers

Chapter 3: Amplitude Modulation: Reception


1. The main problem with the TRF design is
 
    a. Lack of selectivity in receiving all AM stations
    b. Poor demodulation of an AM station
    c. Frustration in tuning to receive more than one station
    d. Lack of sensitivity in receiving all AM stations

2. The sensitivity of a receiver has to do with its ability to

    a. Withstand shock
    b. Receive one station versus another
    c. Receive weak stations
    d. All the above

3. When the input to an ideal nonlinear device is an AM waveform consisting of a    carrier and its
    sidebands, the output of nonlinear mixing produces the original       intelligence because

    a. The intelligence signal is one of its inputs.
    b. A dc component is also produced.
    c. The difference between the carrier and its sidebands is the original        intelligence frequency.
    d. The intelligence frequencies are the upper and the lower sideband frequencies.

4. An AM signal having a carrier frequency of 940 kHz is to be mixed with a local oscillator output signal in
    order to produce an intermediate frequency of 455 kHz. At what should the L.O. frequency be set?
 
    a. 455 kHz
    b. 1395 kHz
    c. 910 kHz
    d. 1850 kHz

5. Diodes that have been specially fabricated to produce a capacitance that varies inversely proportional to
    the amount of reverse bias are called
 
    a. Varactor diodes
    b. Varicap diodes
    c. VVC diodes
    d. All the above

6. The image frequency for a standard broadcast receiver using a 455-kHz IF and tuned to a station at 680
    kHz would be

    a. 1135 kHz
    b. 225 kHz
    c. 1590 kHz
    d. 1815 kHz


7. Double conversion is used to overcome the problem of

    a. Image frequency
    b. Tracking
    c. Diagonal clipping
    d. Poor sensitivity

8. An auxiliary AGC diode

    a. Reduces selectivity
    b. Increases sensitivity
    c. Decreases sensitivity
    d. All the above

9. Which of the following would occur in a receiver not having AGC?

    a. The speaker output level would drastically change while tuning from a weak  signal to a strong signal.
    b. Local stations would easily produce distorted signals in the speaker.
    c. There would be a constant need to readjust the volume control as the weather  and ionosphere change.
    d. All the above

10. The only roadblock to having a complete receiver manufactured on an integrated  circuit is

    a. Tuned circuits and volume controls
    b. Cost
    c. Phase-locked loops
    d. Ceramic filters

11. The decibel difference between the largest tolerable receiver input signal and      its sensitivity is called

     a. The decibel power gain of the receiver
     b. Automatic gain control (AGC)
     c. The dynamic range of the receiver
     d. The IF amplifier gain

12. The simplest AM detector is the

     a. Synchronous detector
     b. Product detector
     c. Heterodyne detector
     d. Diode detector

13. Tracking in a superhet receiver is accomplished using a
 
     a. Trimmer capacitor
     b. Padder capacitor
     c. Varicap diode
     d. a and b
     e. All the above

14. If no stations are picked up on the lower half of the AM band, the likely problem     is

     a. Low RF gain
     b. Poor AGC operation
     c. IF selectivity
     d. LO tracking

15. If no sound is heard from a receiver, the most likely problem area is the
 
     a. Power supply
     b. RF section
     c. Audio amplifier
     d. AGC diode




Answers:



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

1 comment:


  1. Thank you so much for posting a unique post!
    View the latest Bug Detector Device - Portable detector of cell phones, hidden cameras, wiretaps, 5G, Bluetooth, and other hidden devices (9999332099, 9999332499).




    ReplyDelete

Related Posts Plugin for WordPress, Blogger...