Menu
Home / ECE / Communication Systems :: Section 11

ECE :: Communication Systems

Communication Systems - Section 1
Communication Systems - Section 2
Communication Systems - Section 3
Communication Systems - Section 4
Communication Systems - Section 5
Communication Systems - Section 6
Communication Systems - Section 7
Communication Systems - Section 8
Communication Systems - Section 9
Communication Systems - Section 10
Communication Systems - Section 11
Communication Systems - Section 12
Communication Systems - Section 13
Communication Systems - Section 14
Communication Systems - Section 15
Communication Systems - Section 16
Communication Systems - Section 17
Communication Systems - Section 18
Communication Systems - Section 19
Communication Systems - Section 20
Communication Systems - Section 21
Communication Systems - Section 22
Communication Systems - Section 23
Communication Systems - Section 24
Communication Systems - Section 25
Communication Systems - section-26
Communication Systems - Section-27

  1. In the spectrum of an FM wave

    2. A.
    When modulation index is large, carrier frequency disappears
    B.
    carrier frequency cannot disappear
    C.
    amplitude of any side band depends on modulation index
    D.
    the total number of side bands depend on modulation index

    View Answer

    Workspace

    Discuss Discuss in Forum

  2. The reactance of bypass capacitor in a CE amplifier circuit should be

    3. A.
    equal to the resistance in parallel with it
    B.
    equal to 10% or less of the resistance in parallel with it
    C.
    equal to 50% of the resistance in parallel with it
    D.
    independent of the resistance in parallel with it

    View Answer

    Workspace

    Discuss Discuss in Forum

  3. In a radar system the solution to blind speed problem is to

    4. A.
    use MTI
    B.
    use monopoles
    C.
    vary PRF
    D.
    change Doppler frequency

    View Answer

    Workspace

    Discuss Discuss in Forum

  4. For a FM wave carrier modulating frequency is 10 kHz and bandwidth is 2 MHz. If the modulating signal amplitude is doubled, the bandwidth will be

    5. A.
    0.5 MHz
    B.
    1 MHz
    C.
    2 MHz
    D.
    4 MHz

    View Answer

    Workspace

    Discuss Discuss in Forum

  5. In band III of TV, distant reception (beyond line of sight range) is possible due to

    6. A.
    tropospheric bending by refraction
    B.
    reflection of waves
    C.
    ionospheric scattering
    D.
    none of the above

    View Answer

    Workspace

    Discuss Discuss in Forum

  6. In amplitude modulation the rms value of radio frequency voltage after 40% modulation is 60 mV. If modulation is 80% the rms value after modulation will be about

    7. A.
    50 mV
    B.
    60 mV
    C.
    66 mV
    D.
    80 mV

    View Answer

    Workspace

    Discuss Discuss in Forum

  7. 1 GHz is equal to

    8. A.
    106 Hz
    B.
    108 Hz
    C.
    109 Hz
    D.
    1010 Hz

    View Answer

    Workspace

    Discuss Discuss in Forum

  8. Consider the following statements

    1. In a pulsed radar, the transmitted pulses are of high frequency
    2. In a pulsed radar, the transmitted pulses are of high power
    3. In a pulsed radar, the transmitted pulses are of brief duration
    4. In a pulsed radar, the transmitted pulses are of square wave shape.
    Of the above statements the correct statements are

    9. A.
    1 only
    B.
    1, 2 and 3 only
    C.
    1, 2, 3, 4
    D.
    1 and 3 only

    View Answer

    Workspace

    Discuss Discuss in Forum

  9. Probability density function of thermal noise is

    10. A.
    Poisson
    B.
    Binomial
    C.
    Gaussian
    D.
    None of the above

    View Answer

    Workspace

    Discuss Discuss in Forum

  10. In a colour TV receiver AFT stands for

    11. A.
    Automatic Fine Tuning
    B.
    Automatic Frequency Tuning
    C.
    Automatic Field Tuning
    D.
    Alignment Frequency Tuning

    View Answer

    Workspace

    Discuss Discuss in Forum

Java Programming Questions and Answers Interview Questions and Answers