Q. 24 telephone channels are frequency division multiplexed using an SSB modulation. Assuming 3 kHz per channel, the required band width is

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Q. If velocity of sound waves in air at 0°C is 330 m/s, the velocity at 40°C is about

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Q. A 5000 W signal is attenuated by - 196 dB. The resultant signal strength is

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Q. In FM, as bandwidth increases

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Q. A 400 W carrier is amplitude modulated with m = 0.75. If single side band suppressed carrier is used the total power in modulated wave is

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Q. In TV transmitter, the function of duplexer is

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Q. The PSD and the power of a signal g(t) are respectively Sg(ω) and Pg, the PSD and the power of signal a.g(t) are respectively

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Q. The simplest method of suppression of unwanted side band in AM is

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Q. For attenuation of low frequencies we should use

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Q. Assertion (A): A colour TV uses a SAW filter to give stable band pass response and high gain.

Reason (R): Devices using SAW principle are used in many systems.

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Q. In an FM signal, the modulating frequency is 2 kHz and maximum deviation is 10 kHz. The bandwidth requirement is

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Q. The effective length of antenna is different from actual length due to

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Q. In a TV receiver there is no raster, no picture and no sound. The most likely defective stage is

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Q. Noise can be measured by

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Q. A 100 + j 100 Ω load is to be matched to a line with Z0 = 300 Ω to give SWR = 1. The reactance of stub is

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Q. In VHS format each video head is tilted from azimuth by

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Q. The number of possible colours with a 4 line digital input monitor are

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Q. Convolution of x(t + 5) with impulse function δ(t - 7) is equal to

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Q. Which of the following is a better recording medium?

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Q. An angle modulated signal is given by s(t) = cos 2π (2 x 10⁶t + 30 sin 150t + 40 cos 150t). The maximum frequency and phase deviations of s(t) are

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