MCQOPTIONS
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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Circular polarization involves critical alignment between transmitting and receiving antenna. |
| A. | true |
| B. | false |
| Answer» C. | |
| 2. |
Which polarization is used to reduce the depolarization effect on received waves? |
| A. | circular polarization |
| B. | linear polarization |
| C. | atomic polarization |
| D. | dipolar polarization |
| Answer» B. linear polarization | |
| 3. |
A cordless telephone that uses separate frequencies for transmission in base and portable units is called |
| A. | half duplex |
| B. | duplex |
| C. | simplex |
| D. | one-way communication |
| Answer» C. simplex | |
| 4. |
VSB modulation is used in televisions because it avoids phase distortion at low frequencies. |
| A. | true |
| B. | false |
| Answer» C. | |
| 5. |
Single Sideband Modulation (SSB) is generally reserved for point-to-point communication. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 6. |
A duplex arrangement use separate frequencies for transmission. |
| A. | true |
| B. | false |
| C. | topic 1.3 ssbsc |
| Answer» B. false | |
| 7. |
Phase array radar can track many targets together. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 8. |
A narrow band noise can exist in |
| A. | am only |
| B. | pcm only |
| C. | fm only |
| D. | am and fm both |
| Answer» E. | |
| 9. |
The upper and lower sideband frequencies for 5KHz amplitude modulation with a 30KHz carrier frequency will be? |
| A. | 35khz and 25khz |
| B. | 34khz and 24khz |
| C. | 25khz and 35khz |
| D. | 0.35khz and 0.25khz |
| Answer» B. 34khz and 24khz | |
| 10. |
When noise is passed through a narrow band filter, the output of filter should be? |
| A. | triangular |
| B. | square |
| C. | parabolic |
| D. | sinusoidal |
| Answer» E. | |
| 11. |
For which of the modulated system, the linear amplified modulated stage is used? |
| A. | low level amplitude modulated system |
| B. | high level amplitude modulated system |
| C. | high level frequency modulated system |
| D. | low level frequency modulated system |
| Answer» B. high level amplitude modulated system | |
| 12. |
For an AM transmitter, class C amplifier can be used after the modulation stage. |
| A. | true |
| B. | false |
| Answer» C. | |
| 13. |
Function of duplexer in a RADAR is to permit the use of same antenna for transmission and reception. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 14. |
Which of the following stage is present in FM receiver but not in AM receiver? |
| A. | amplitude limiter |
| B. | demodulator |
| C. | am amplifier |
| D. | mixer |
| Answer» B. demodulator | |
| 15. |
AM system use only product detector for demodulation. They never use envelope detectors. |
| A. | true |
| B. | false |
| Answer» C. | |
| 16. |
A product detector in AM systems is also called |
| A. | envelope detector |
| B. | differentiator |
| C. | integrator |
| D. | phase detector |
| Answer» E. | |
| 17. |
LCD uses |
| A. | sematic crystals |
| B. | twisted nematic crystals |
| C. | nematic crystals |
| D. | cholesteric crystals |
| Answer» C. nematic crystals | |
| 18. |
AM demodulation technique can be divided into            and            demodulation. |
| A. | direct, indirect |
| B. | slope detector, zero crossing |
| C. | coherent, noncoherent |
| D. | quadrature detection, coherent detection |
| Answer» D. quadrature detection, coherent detection | |
| 19. |
Non coherent detection requires the knowledge of transmitted carrier frequency and phase at the receiver. |
| A. | true |
| B. | false |
| Answer» C. | |
| 20. |
FFSR in AM systems stands for |
| A. | feedforward signal regeneration |
| B. | feedbackward signal regeneration |
| C. | feedbackward system restoration |
| D. | feedforward system restoration |
| Answer» B. feedbackward signal regeneration | |
| 21. |
Which of the following is a disadvantage of tone-in-band SSB system? |
| A. | high bandwidth |
| B. | bad adjacent channel protection |
| C. | effects of multipath |
| D. | generation and reception of signal is complicated |
| Answer» E. | |
| 22. |
How is the performance of SSB AM systems in fading channels? |
| A. | poor |
| B. | best |
| C. | good |
| D. | average |
| Answer» B. best | |
| 23. |
Single sideband AM systems occupy same bandwidth as of conventional AM systems. |
| A. | true |
| B. | false |
| Answer» C. | |
| 24. |
A percentage of modulation greater than |
| A. | 10% |
| B. | 25% |
| C. | 50% |
| D. | 100% |
| Answer» E. | |
| 25. |
If the peak message signal amplitude is half the peak amplitude of the carrier signal, the signal is            modulated. |
| A. | 100% |
| B. | 0.02 |
| C. | 0.5 |
| D. | 0.7 |
| Answer» D. 0.7 | |