Test: Communication Systems - 8 - Electronics and Communication Engineering (ECE) MCQ

A TV remote control works on the principle of

To prevent overloading in the last IF amplifier one should use

Push pull amplifier is

The tape recorders used in homes have

In a communication system, noise is most likely to affect the signal

Assertion (A): CCIR-B system has 625 scanning lines per frame and 2 : 1 interlace.

Reason (R): The aspect ratio is 4 : 3

Each frequency in the modulating wave gives rise to four side bands.

In VHS format each video head is tilted from azimuth by

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

Which of the following is a better recording medium?

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

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

The PSD and the power of a signal g(t) are respectively S_g(ω) and P_g, the PSD and the power of signal a.g(t) are respectively

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

In a 100% amplitude modulated signal, the power in the upper sideband when carrier power is to be 100 W and modulation system SSBSC, is

For attenuation of low frequencies we should use

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.

At night the ionosphere can be considered to be consisting of

Which one of the following is true?

A balun transformer gives an impedance transformation of

The EHT voltage in a picture tube of TV is

A 1000 kHz carrier wave modulated 40% at 40000 Hz is applied to a resonant circuit tuned to a carrier frequency and having Q = 140. What is the degree of modulator after transmission through the circuit?