Multiple Choice Questions (MCQ) on Electronics and Communication Engineering

26-Temperature coefficient of Silicon diode at room temperature is

(A) -1.22 mV/°C

(B) -1.42 mV/°C

(C) -1.62 mV/°C

(D) -2.00 mV/°C

 

27-The capacitance in parallel with forward biased base emitter terminals of a transistor is known as:

(A) Depletion Capacitance

(B) Drift Capacitance

(C) Diffusion Capacitance

(D) Doping Capacitance

 

28-Terminal current gain for the common emitter amplifier is:

(A) ratio of Collector current to Base current

(B) ratio of current delivered to load to current supplied to base

(C) β of the transistor

(D) all the above

 

29-Fastest of all logic families:

(A) Emitter coupled logic

(B) Resistor Transistor logic

(C) CMOS logic

(D) Transistor – Transistor logic

 

30-Nosie due to random emission of electrons associated with charge flowing across a potential barrier is known as

(A) Thermal noise

(B) White noise

(C) Cosmic noise

(D) Shot noise

 

31-A broadcast radio transmitter radiates 5 kW power when the modulation percentage is 60%. The carrier power is

(A) 1.19 kW

(B) 3.12 kW

(C) 4.23 kW

(D) 6.46 kW

 

32-The advantages of DSB over SSB full carrier AM is:

(A) Less available channel space

(B) More stable transmitter gives better reception

(C) More power to transmit same signal

(D) Signal is less resistant to noise

 

33-VSB modulation is preferred in TV because:

(A) it avoids phase distortion at low temperature

(B) it reduces the bandwidth requirement to half

(C) it results in better reception

(D) all the above

 

34-Which of the following is the indirect way of FM generation?

(A) Reactance bipolar transistor modulator

(B) Armstrong modulator

(C) Varactor diode modulator

(D) Reactance FM modulator

 

35-The impulse response of a linear interpolator is:

(A) A square pulse

(B) Rectangular pulse

(C) Linear ramp

(D) Triangular pulse

 

ANSWERS:

26-(D), 27-(C), 28-(A), 29-(A), 30-(D), 31-(C), 32-(C), 33-(B), 34-(B), 35-(D)