Q. Assertion (A): The colour signal consists of only luminance signal

Reason (R): In India PAL colour signal system is used.

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Q. To separate channels in FDM receiver we have to use

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Q. A device with input x(t) and y(t) is characterized by y(t) = x²(t). An FM signal with frequency deviation of 90 kHz and modulating signal bandwidth of 5 kHz is applied to this device. The bandwidth of the output signal is

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Q. Assertion (A): Bandwidth of a TV signal is 5 MHz.

Reason (R): TV systems use vestigial side band transmission.

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Q. In a satellite system circular polarization is to be obtained. The antenna used is

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Q. A horizontal output stage is cutoff for retrace and 40% of trace. If time for each horizontal line is 64 μs and retrace time is 12 μs, the transistor is conducting for about

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Q. A TV remote control works on the principle of

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Q. As the magnitude of reverse bias is increased, the capacitance of varactor diode

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Q. To prevent overloading in the last IF amplifier one should use

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Q. The number of spectral component when two cosine waves are multiplied of different frequency

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Q. Radiation resistance of an antenna is a

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Q. A 1 MHz sinusoidal carrier is amplitude modulated by a symmetrical square wave of period 100 μ sec. Which of the following frequencies will not be in the modulated signal?

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Q. The input to a coherent detector is DSB - SC signal plus noise. The noise at the detector output is

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Q. All of the output pulses are at full transmitter power for a strong signal in all of the following except

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Q. LCD uses

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Q. Which of the following stage is not present in AM receiver as compared to FM receiver?

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Q. The function of duplexer in a RADAR is

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Q. If e = 10 cos (2π x 10⁸t + 20 cos 2π 10³t). The bandwidth is

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Q. In FM, as the modulating frequency decreases and the modulating voltage amplitude

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Q. A pure tone at 1000 Hz has a dB level of 40 dB. If the required dB level is 100, the number of such tones is

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