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)