Menu
Home / ECE / Communication Systems :: Section 16

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. The block diagram of AM transmitter in which high level modulation is used as shown in figure. The block X could be

    2. A.
    audio power amplifier
    B.
    buffer RF amplifier
    C.
    compressor amplifier
    D.
    none of the above

    View Answer

    Workspace

    Discuss Discuss in Forum

  2. In FM 'guard band' is provided

    3. A.
    to limit upper frequency limit
    B.
    to limit lower frequency limit
    C.
    so that there is less adjacent channel interference
    D.
    to limit transmitted power of a station

    View Answer

    Workspace

    Discuss Discuss in Forum

  3. Assertion (A): FM requires more bandwidth than AM

    Reason (R): Wide band FM is used for broadcast transmissions.

    4. A.
    Both A and R are correct and R is correct explanation of A
    B.
    Both A and R are correct but R is not correct explanation of A
    C.
    A is correct but R is wrong
    D.
    A is wrong but R is correct

    View Answer

    Workspace

    Discuss Discuss in Forum

  4. When E1, E2, E3 etc. are the simultaneous modulating voltages, then the total modulating voltage Et will be

    5. A.
    Et = E1 + E2 + E3 + ...
    B.
    Et= E12 + E22 + E32 + ...
    C.
    D.

    View Answer

    Workspace

    Discuss Discuss in Forum

  5. A frequency doubler has an FM signal input at 13 MHz with a deviation of 5 kHz. The output, frequency for the carrier will be

    6. A.
    26 MHz
    B.
    26.1 MHz
    C.
    10 kHz
    D.
    160 kHz

    View Answer

    Workspace

    Discuss Discuss in Forum

  6. In MF range, increasing the transmitter power

    7. A.
    increases the range of transmitter
    B.
    does not increase the range of transmitter because propagation is limited by tilt
    C.
    decreases the range of transmitter because propagation is limited by tilt
    D.
    increases the range of transmitter because propagation is through space waves

    View Answer

    Workspace

    Discuss Discuss in Forum

  7. The most frequent users of long distance VLF transmission is

    8. A.
    ship communication
    B.
    radio broadcasting
    C.
    TV broadcasting
    D.
    telephone and telegraph

    View Answer

    Workspace

    Discuss Discuss in Forum

  8. BFO stands for

    9. A.
    Beat Frequency Oscillator
    B.
    Broad Frequency Oscillator
    C.
    Blocking Frequency Oscillator
    D.
    Ballistic Frequency Oscillator

    View Answer

    Workspace

    Discuss Discuss in Forum

  9. SSB-SC stands for

    10. A.
    Single Side Band-Suppressed Carrier
    B.
    Single Side Band-Synchronous Carrier
    C.
    Synchronous Side Band-Suppressed Carrier
    D.
    Synchronous Side Band-Self Carrier

    View Answer

    Workspace

    Discuss Discuss in Forum

  10. A lens has a hyperfocal distance of 7.5 m. It is focused at 7.5 m. Then

    11. A.
    all objects from 7.5 m to infinity will appear in focus
    B.
    all objects from 3.75 m to infinity will appear in focus
    C.
    all objects from 0 to 7.5 m will appear in focus
    D.
    all objects from 0 to 3.75 m will appear in focus

    View Answer

    Workspace

    Discuss Discuss in Forum

Java Programming Questions and Answers Interview Questions and Answers