Q. Assertion (A): A video monitor does not need RF tuner and IF amplifier

Reason (R): The picture tube in TV is basically a CRT.

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Q. Consider the following statements as regards IF in radio receivers

1. If IF is too high, poor selectivity and poor adjacent channel rejection could result
2. If IF is high, tracking difficulties increase
3. A very low IF makes selectivity too sharp
4. As IF is decreased, image frequency rejection becomes better

Which of the above are correct?

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Q. Audio-signal modulates a 125 MHz carrier, causing a frequency deviation of 5 kHz. The bandwidth of the narrowband FM signal is __________ kHz.

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Q. Assertion (A): Radar gave birth to microwave technology.

Reason (R): In radar systems very high frequencies give the most accurate results.

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Q. A channel has a SNR of 7 and BW 4 kHz. Keeping the channel capacity (BPS) same, the BW is reduced to accommodate more channels. The SNR

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Q. In amplitude modulation the rms value of radio frequency voltage after 40% modulation is 60 mV. If modulation is 80% the rms value after modulation will be about

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Q. 1 GHz is equal to

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Q. Consider the following statements

1. In a pulsed radar, the transmitted pulses are of high frequency
2. In a pulsed radar, the transmitted pulses are of high power
3. In a pulsed radar, the transmitted pulses are of brief duration
4. In a pulsed radar, the transmitted pulses are of square wave shape.

Of the above statements the correct statements are

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Q. Probability density function of thermal noise is

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Q. In a colour TV receiver AFT stands for

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Q. The smallest change in sound intensity that can be detected by human ear is __________ dB.

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Q. Low frequency boost can be easily compensated by

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Q. An MTI compares a set of received echos with those received during the previous sweep.

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Q. If e = 10 sin(10⁸ t + 3 sin 10⁴ t) then the deviation is

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Q. When a complex signals is used to frequency modulate a carrier, the resulting sideband distribution is

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Q. The output VR of the ratio detector is related with the output VF of similar Foster-Seeley discriminator as follows.

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Q. In grid bias modulation system the power required for modulating amplifier

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Q. In spread spectrum technique

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Q. QAM stands for

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Q. The bandwidth required for amplitude modulation is

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