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Double side band modulator is used to obtain :
(A) Double side band suppressed carrier signal
(B) Single side band suppressed carrier signal
(C) Double side band signal
(D) Single side band signal

VSB modulation is preferred in TV because :
(५) it avoids phase distortion at low frequencies
(B) it reduces the bandwidth requirement to half
(C) 1 results in better reception
(D) all the above

Which of the following is the indirect way of I'M generation?
(ಗಿ) Reactance bipolar transistor modulator
(B) Armstrong modulator
)0 Varactor diode modulator
(D) Reactance FM modulator

An FM signal with a deviation 2 is passed through a mixer and has its frequency reduced to
half. The deviation in the output of the mixture is :

(A) 2 (೫) 28
(©) 4 (D) 9

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?

(A) 1002 kHz (B) 1000 kHz
(C) 999.2 kHz (D) 998.0 kHz

In the spectrum of a FM wave :
(A) The carrier frequency disappears when the modulation index is large
(B) The amplitude of any side band depends upon the modulation index
(C) The total number of side band depends upon modulation index
(D) The number of side bands increase with increase in modulation frequency

Amplitude limiting action is achieved in :
(^) Foster-Seely discriminator (B) Quadrature Detector
(C) PLL demodulator (D) Ratio detector

046/2016 6 A