MCQOPTIONS
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MCQOPTIONS
This section includes 19 Mcqs, each offering curated multiple-choice questions to sharpen your Analog Communications knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Aliasing refers to ________ |
| A. | Sampling of signals less than at Nyquist rate |
| B. | Sampling of signals at Nyquist rate |
| C. | Sampling of signals greater than at Nyquist rate |
| D. | Unsampled the original signal |
| Answer» B. Sampling of signals at Nyquist rate | |
| 2. |
Signal to quantization noise ratio in PCM system depends on _________ |
| A. | sampling rate |
| B. | signal bandwidth |
| C. | number of quantization levels |
| D. | bit rate |
| Answer» D. bit rate | |
| 3. |
What is the carrier power of an un-modulated carrier signal when it is transmitted through an antenna having an impedance of 50? and it produces a current of 5.4A? |
| A. | 1458W |
| B. | 1468W |
| C. | 1478W |
| D. | 1488W |
| Answer» B. 1468W | |
| 4. |
Find the total power, if the carrier of an AM transmitter is 800W and it is modulated to 50%? |
| A. | 100W |
| B. | 800W |
| C. | 500W |
| D. | 900W |
| Answer» E. | |
| 5. |
Audio frequency range lies between _________ |
| A. | 2 MHz to 20 MHz |
| B. | 20 Hz to 20 KHz |
| C. | 20 KHz to 200 KHz |
| D. | 20 MHz to 200 MHz |
| Answer» C. 20 KHz to 200 KHz | |
| 6. |
Communication consists of electrical means of sending information only. |
| A. | True |
| B. | False |
| Answer» C. | |
| 7. |
Which statement is true about emitter modulator amplifier for amplitude modulation? |
| A. | operates in class A mode |
| B. | operates in class C mode |
| C. | operates in class B mode |
| D. | operates in class D mode |
| Answer» B. operates in class C mode | |
| 8. |
In communication system, redundancy ________ |
| A. | Helps to detect error |
| B. | Helps to correct error |
| C. | Reduces efficiency of communication |
| D. | Helps to detect and correct error and also reduces efficiency |
| Answer» E. | |
| 9. |
Which of the following statement is not true about auto-correlation function? |
| A. | it is non-unique description of goals |
| B. | it is measure of both time variation and statistical dependence |
| C. | it is an average function |
| D. | it is defined only for periodic signals |
| Answer» E. | |
| 10. |
Auto-correlation function is non-unique description of signals. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 11. |
What is the auto-correlation function of a signal (t) at t0=0? |
| A. | It is equal to average voltage of the signal |
| B. | It is equal to average power of the signal |
| C. | It is equal to zero |
| D. | It is equal to infinite |
| Answer» C. It is equal to zero | |
| 12. |
Bandwidth of RF amplifier for a color TV receiver is ________ |
| A. | equal to channel width |
| B. | more than channel width |
| C. | less than channel width |
| D. | twice of channel width |
| Answer» C. less than channel width | |
| 13. |
In automatic gain control of the AM receiver ________ |
| A. | gain of the receiver is adjusted |
| B. | gain adjustment depends upon the strength of received signal |
| C. | is an open-loop system |
| D. | gain is received only by stronger signals |
| Answer» B. gain adjustment depends upon the strength of received signal | |
| 14. |
Which of the following is an example of continuous wave analog modulation? |
| A. | PCM |
| B. | DPCM |
| C. | AM |
| D. | ADM |
| Answer» D. ADM | |
| 15. |
Modulation is used to separate differing transmission. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 16. |
The output stage of television transmitters is most likely to be a __________ |
| A. | Grid modulated class C amplifier |
| B. | Grid modulated class A amplifier |
| C. | Plate modulated class C amplifier |
| D. | Plate modulated class A amplifier |
| Answer» B. Grid modulated class A amplifier | |
| 17. |
A function f(x) is odd, when? |
| A. | f(x) = -f(x) |
| B. | f(x) = f(-x) |
| C. | f(x) = -f(x)f(-x) |
| D. | f(x) = f(x)f(-x) |
| Answer» B. f(x) = f(-x) | |
| 18. |
The amount of frequency deviation in FM signal depends on ________ |
| A. | Modulating frequency |
| B. | Modulation Index |
| C. | Amplitude of the modulating signal |
| D. | Carrier frequency |
| Answer» D. Carrier frequency | |
| 19. |
What is the function of frequency mixer in super heterodyne receiver? |
| A. | Multiplication of incoming signal and the locally generated carrier |
| B. | Addition of incoming signal and the locally generated carrier |
| C. | Amplification |
| D. | Filtering |
| Answer» B. Addition of incoming signal and the locally generated carrier | |