Home / ECE / Radio Receivers :: Section 1

ECE :: Radio Receivers

  1. Which are the popular IF frequencies for microwave and radar receivers operating on frequencies in the range 1 to 10 GHz

  2. A.
    30, 60 and 70 kHz
    B.
    3, 6 and 7 kHz
    C.
    30, 60 and 70 MHz
    D.
    3, 6 and 7 GHz

    View Answer

    Workspace

    Discuss Discuss in Forum


  3. In a ratio detector

  4. A.
    the linearity is worse than in a phase discriminator
    B.
    the output is twice that obtainable from a similar phase discriminator
    C.
    stabilization against signal strength variations is provided
    D.
    the circuit is the same as in a discriminator, except that the diodes are reversed

    View Answer

    Workspace

    Discuss Discuss in Forum


  5. Neutralization is used in RF amplifiers to

  6. A.
    stop oscillation
    B.
    increase bandwidth
    C.
    improve selectivity
    D.
    all of the above

    View Answer

    Workspace

    Discuss Discuss in Forum


  7. When fs is the signal frequency and fi is the intermediate frequency, then image frequency fsi is given by

  8. A.
    fsi = fs - 2fi
    B.
    fsi = fs + 2fi
    C.
    D.

    View Answer

    Workspace

    Discuss Discuss in Forum


  9. It is known that noise phase modulates the FM wave. As the noise side band frequency approaches the carrier frequency, the noise amplitude

  10. A.
    will increase
    B.
    will decrease
    C.
    will remain constant
    D.
    will reduce to negligible value

    View Answer

    Workspace

    Discuss Discuss in Forum


  11. In a receiver, which of the following device has IF input but RF output?

  12. A.
    Demodulator
    B.
    Loudspeaker
    C.
    Audio amplifier
    D.
    Frequency changer

    View Answer

    Workspace

    Discuss Discuss in Forum


  13. Transistor are free from which type of noise?

  14. A.
    Resistance noise
    B.
    Partition noise
    C.
    Flicker noise
    D.
    Shot noise

    View Answer

    Workspace

    Discuss Discuss in Forum


  15. Standard AM radio broadcasts are confined to

  16. A.
    MF
    B.
    HF
    C.
    VHF
    D.
    UHF

    View Answer

    Workspace

    Discuss Discuss in Forum


  17. In a radio receiver with simple AGC

  18. A.
    the highest AGC voltage is produced between stations
    B.
    the faster the AGC time constant, the more accurate the output
    C.
    an increase in signal strength produces more AGC
    D.
    the audio stage gain is normally controlled by AGC

    View Answer

    Workspace

    Discuss Discuss in Forum


  19. Which of the following cannot be used to demodulate SSB?

  20. A.
    Complete phase-shift generator
    B.
    Product detector
    C.
    Diode balanced modulator
    D.
    Bipolar transistor balanced modulator

    View Answer

    Workspace

    Discuss Discuss in Forum