1. The colour subcarrier and sidebands produced by its modulation with the chrominance signals are accommodated in the standard channel width by the process of
2. In FM signal with a modulation index mf is passed through a frequency tripler. The wave in the output of the tripler will have a modulation index of
3. In colour TV receiver, varactor diode is used for
4. The number of noise sources in a BJT are
5. Energy content of atmospheric noise
6. A 400 W carrier is amplitude modulated with m = 0.75. The total power in AM is
7. c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM signal is three times the transmission bandwidth of the AM signal, then the coefficient of the term cos [2p (1008 x 103t)] in the FM signal (in terms of the Bessel Coefficients) is
8. Non-coherently detection is not possible for
9. Tracking of extra terrestrial objects requires
10. Assertion (A): Free space does not interfere with normal radiation and propagation of radio wavesReason (R): Free space has no magnetic or gravitational fields.
11. In radar systems PRF stands for
12. Which of the following cannot be the Fourier series expansion of a periodic signal?
13. Which of the following is the indirect way of FM generation?
14. A telephone exchange has 9000 subscribers. If the number of calls originating at peak time is 10, 000 in one hour, the calling rate is
15. The famous book ‘Lycidas’ is written by?
16. As the frequency increases, the absorption of ground wave by earth's surface
17. The velocity of sound waves in air
18. The range of a cordless telephone is about
19. An earth mat for a communication tower consists of
20. Degaussing in a picture tube means
21. The rate at which information can be carried through a communication channel depends on
22. Some types of traps used in video IF amplifier of colour TV are
23. Direct and reflected sound waves may interfere with each other.
24. A carrier is simultaneously modulated by two sine waves having modulation indices of 0.4 and 0.3. The total modulation index will be
25. A 1000 kHz carrier is simultaneously modulated with 300 Hz, 800 Hz and 2 kHz audio sine waves. Which of the following frequency is least likely to be present in the output?