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1. In a communication system noise effects the signal mostly in the channel
2. Modulation is used to reduce the bandwidth.
3. Communication consists of the electrical mean of sending, receiving, and processing Information.
4. The output stage of a television transmitter is mostly likely to be a grid-modulated class-C amplifier.
5. When signal amplitude is equal to the amplitude of the carrier, the percentage modulation factor will 50.
6. Amplitude modulation is used for broadcasting because as compared to other systems lts use avoids receiver complexity.
7. High intermediate frequency in a superhet receiver increase tracking problems.
8. The noise performance of a square law demodulator of AM signal is better than that of a synchronous detector.
9. The difference between phase and frequency modulation lies in the different definition of the modulation index.
10. The noise performance of a wideband FM systems exhibits a threshold.
11.The coupling used in stoneman transmission bridge is capacitive.
12. The quantisation noise in a PCM system, depends upon the number f quantisation levels only.
13. In a low-level modulation system, the amplifiers following the modulated stage should be only linear amplifier.
14. In a low-level amplitude modulation systems, the amplifiers following the modulated stage should be a linear device.
15 .Advantage of FM over AM Better noise immunity is provided, the transmitted power is more useful, less modulating power is required.
16. In FM, the frequency deviation is proportional to amplitude of modulating signal.
17. PPM is digital modulation technique.
18. In a carbon microphone, the electrical power output less than The incident acoustical.
19. The household radio receiver uses enyelope Detector.
20. In TV, the vertical synchronizing pulses occur after every frame.
21. Horizontal retrace in a TV receiver is also known as flyback.
22. In Indian TV systems, the number of frames per seconds 25.
23. The signal-to-quantisation noise ratio in a PCM systems depends upon number of quantisation levels.
24. One can provides two or more voice circuits on the same carrier by using ISB systems.
25. 100% modulation is produced in AM when carrier amplitude equals signal amplitude.
26. Neper is larger than decibel.
27. Modulation is the process combing the audio and radio frequency waves at the transmitting end of a communication systems.
28. Sone is the unit of loudness.
29. For a given carrier wave maximum undistorted power is transmitted when value of modulation is 1.0
30. The output of a vertical amplifier, applied to the yoke in a TV receiver, consists of a saw tooth voltage.
31. A frequency multiplier circuits is tuned to a harmonic of the input signal.
32. At high frequencies the noise that becomes predominant is transit time noise.
33. To compare the noise performance of the receiver this of the following quantities is used. Noise figure, noise performance and equivalent noise resistance.
34. A receiver has poor IF selectivity. It implies that it will also have blocking.
35. The noise generated by a resistor depends upon its operating temperature.
36. Most of the amplification of the received signal is obtained in a superheterodyne receiver from the IF stage.
37 Three points tracking is achieved with which of the following? The podder capacitor.
38. In RF amplifiers neutralisation is used to stop oscillation.