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ECE :: Communication Systems

  1. For TV broadcast, picture signal is modulated in

  2. A.
    SSB
    B.
    VSB
    C.
    FM
    D.
    AM

  3. Assertion (A): Stubs, directional couplers and baluns are very commonly used in communication systems

    Reason (R): Characteristic impedance of a line is an important parameter.

  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

  5. Audio frequency range lies between

  6. A.
    20 Hz and 20 kHz
    B.
    20 kHz and 20 MHz
    C.
    2 MHz and 20 MHz
    D.
    20 MHz and 200 MHz

  7. Assertion (A): SSB and ISB receivers have good S/N ratio

    Reason (R): SSB and ISB receivers have good suppression of adjacent channels.

  8. 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

  9. De-emphasis circuit is used

  10. A.
    to attenuate high frequencies
    B.
    to attenuate low frequencies
    C.
    to attenuate mid-band frequencies
    D.
    None of the above

  11. Which one of the following frequency bands is allocated by ITU (International Telecomm. Union) for DBS - (Direct Broadcast service) also referred as DTH - (Direct to Home service)?


  12. FM broadcast lies in which band?

  13. A.
    HF
    B.
    SHF
    C.
    UHF
    D.
    VHF

  14. Which colour picture tube uses slotted aperture mask?

  15. A.
    Trinitron
    B.
    Shadow mask tube
    C.
    PIL
    D.
    None of the above

  16. If the circumference of a spherical target is between 1 to 10 wavelength in a radar system, the situation is called

  17. A.
    resonance region
    B.
    Rayleigh region
    C.
    optical region
    D.
    binomial region

  18. The complete video signal consists of

  19. A.
    video signal and synchronising pulses
    B.
    video signal, synchronising pulses and blanking pulses
    C.
    video signal corresponding to picture information only
    D.
    video signal and blanking pulses