ISRO Scientist/Engineer ECE Solved Papers
Practice previous years' questions for Electromagnetics, Antennas, Microwave Engineering, Digital Communication, Signals & Systems, Analog Electronics, VLSI, and Optical Communications.
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Marking scheme: +3.00 positive, -0.75 negative (ICRB Standard).
What is the average probability of error with two symbols 0 and 1 with source probability 0.2, 0.8 respectively transmitted over a binary asymmetric channel as given below:
The minimum distance required for a linear block code to achieve a guaranteed correction of up to 5 errors is
The Lower Threshold Point (LTP) voltage of the Schmitt trigger with an ideal op-amp shown in Figure is
An ideal comparator is fed with a sine wave of 4Vpp (peak-to-peak) with zero DC component as shown in Figure. The reference voltage of the comparator is 1 V. What is the duty cycle of the output $V_{\text{out}}$?
Which of the following represents the correct output $V_o$ of circuit shown in Figure? Assume $RC = 1$.
An 8-bit Digital-to-Analog converter (DAC) using two identical 4-bit DACs with equal reference voltage is shown in Figure. If $b_0$ represents LSB, $b_7$ MSB and the op-amp is ideal, to obtain correct analog values corresponding to an 8-bit DAC at the output $V_o$, what should be the value of resistor R?
Which of the following is the error transfer function for negative feedback?
The following system $\frac{4s + 1}{4s^2 + 1}$ is
The bode plot of the delay transfer function $e^{-3s}$ has the following shape
What is the correct statement of the Cauchy residue theorem used in the Nyquist criterion (m and n are the number of poles and zeros respectively)?
When converting the following system into the standard state space form $\ddot{x} + 3\dot{x} - 9x = 3 \sin(\omega t)$ the resultant A matrix is
The matrix used for calculating the controllability is
The standard form of a PID controller is
For a standard second order polynomial given by $G(s) = a_2 s^2 + a_1 s + a_0$ according to the Routh test, the stability criterion is given by
Two infinitely long wire separated by a distance 5 m, carrying current I in opposite direction. If $I = 10\text{A}$ then the magnetic field intensity at point 'P' (located between the wires at a distance of 1 m from the right-hand wire) is:
Characteristic impedance of a transmission line is 50 Ω. Input impedance of open circuited line is $Z_{oc} = 100 + j150\ \Omega$. The value of short circuited input impedance is
The characteristic equation of a closed loop system is $s^2 + 2s + 2 = 0$. Then the system is
A 12V battery discharges for 20 minutes at a constant current of 2A and terminal voltage drops linearly from 12V to 10V. What is the total energy delivery by the battery during this time?
In the given circuit, if $I_1 = 10\text{A}$, calculate the value of $V_s$:
Find $V_A$ in the given circuit:
For obtaining maximum power from a solar cell, it should operate on which portion of its V-I characteristics?
Commonly used Thermistors for temperature measurement have
Change in magnetic flux in coil of 30 turns is 0.1 weber/second. What is the value of induced EMF?
Neglecting saturation, if the current taken by DC series motor is increased from 10A to 12A, percentage increase in the torque will be
A DC shunt generator produces 450A at 230V. The resistance of shunt field and armature are 50 ohms and 0.025 ohm respectively. The armature voltage drop will be