Practice previous years' questions for Electromagnetics, Antennas, Microwave Engineering, Digital Communication, Signals & Systems, Analog Electronics, VLSI, and Optical Communications.
Marking scheme: +3.00 positive, -0.75 negative (ICRB Standard).
For a 10 bit PCM system the signal to quantization noise ratio is 62dB. If the number of bits is increased by 2, then the signal to quantization noise ratio will
The modulation normally used with the digital data is
The critical angle $\theta_c$ in an optical fiber is given by _____ Where $n_1$ is refractive index of medium 1 and $n_2$ is the refractive index of medium 2.
In a JK flip flop we have $J = Q'$ and $K = 1$. Assuming that the flip flop was initially cleared and clocked for 6 pulses, the sequence at the Q output will be
Which of the following system is linear
Which of the following operator cannot be synthesized by VHDL synthesis tools
Which of the following statements with reference to a generic microprocessor is correct?
An electric iron designed for 110V AC supply was rated at 500W. It was put across a 220V supply. Assuming that at 110V it supplied 500W output (i.e no losses) at the new voltage it will supply
A very lossy, $\lambda/4$ long, 50 ohm transmission line is open circuited at the load end. The input impedance measured at the other end of the line is approximately.
For the 2N338 transistor, the manufacturer specifies $P_{\max} = 100\text{mW}$ at $25^\circ\text{C}$ free air temperature and the maximum junction temperature, $T_{j\max} = 125^\circ\text{C}.$ Its thermal resistance is
In a Class AB amplifier, the current flows through the active device for
Which of the following is not true regarding a preemptive kernel
The solution of differential equation $dy/dx = e^{x-y} + x^2 e^{-y}$ is
The intermediate frequency of a super-heterodyne receiver is 450 KHz. If it is tuned to 1200 KHz, the image frequency will be
The bandwidth of a 'N' bit binary coded PCM signal for modulating a signal having bandwidth of 'f' Hz is
Go-stationary satellites are placed in equatorial orbits at the height approximately
For a single mode optical cable with 0.25dB/km loss, the optical power 100km from a 0.1mW source will be
The function of a strobe function in digital system is
The impulse response of a linear time invariant system is $h(n) = \{1, \underline{2}, 1, -1\}$. The response for the input signal $x(n) = \{\underline{1}, 2, 3, 1\}$ is
Which of the following statement regarding a constant is not true
In a 8085 microprocessor system with memory mapped I/O
The Thevenin and Norton circuits are
A broadside array operating at 100 cm wavelength consist of 4 half wave dipoles spaced 50 cm apart. Each element carries radio frequency current in the same phase and of magnitude 0.5A. The radiated power will be _____ if the radiation resistance is 146 ohm.
An NPN transistor has a beta cut off frequency $f_\beta$ of 1MHz, and a common emitter short circuit low frequency current gain $\beta_0$ of 200. its unity gain frequency $f_T$ and the alpha cut-off frequency $f_\alpha$ respectively are
For a class B amplifier providing a 20V peak signal to 16 ohm load and a power supply of $V_{cc} = 30\text{V}$ the efficiency will be.