Code: 9A02401 PRINCIPLES OF ELECTRICAL ENGINEERING (Common to ECE, EIE, E.Con.E & ECC) 1 Find initial conditions for voltage across capacitor, the currents i 1, i 2 and the derivatives for the circuit shown in fig. below. Take R 1 =10 Ω. 2 (a) Derive the relation between Y and ABCD parameters. (b) A two port network has the following parameters: Z 11 = 4 Ω, Z 12 = 1 Ω, Z 21 = 3 Ω and Z 22 = 3 Ω. Calculate transmission parameters. 3 Design a constant-k band rejection filter having the cut off frequencies f 1 = 1250 Hz and f 2 = 6000 Hz and a characteristic impedance Z 0 = 500 Ω. 4 (a) What is an attenuator? Derive the design equations for Bridged T-type attenuator. (b) Design a π-type attenuator to give 20 db attenuation and to have a characteristic impedance of 50 Ω. 5 Explain the characteristics of DC generator in detail. 6 What is the aim of Swinburne s test? Explain the procedure with a neat circuit diagram. 7 A single phase transformer working at 0.6 power factor has an efficiency of 75% at both half load, at full load of 2 kw. Determine the efficiency at 90% of full load. 8 (a) Explain the principle of operation of AC servo motor. (b) Explain the characteristics of capacitor motor.
Code: 9A04401 SWITCHING THEORY & LOGIC DESIGN (Common to EEE, ECE, EIE, E.Con.E & ECC) 1 (a) Explain the ASCII code with table. (b) Encode the following text in to 7-bit ASCII code: JNTU ANANTAPUR 2 (a) Prove that OR-AND network is equivalent to NOR-NOR network. (b) Simplify the following Boolean functions to minimum number of literals: (i) x + y + xyz (ii) (x + xyz ) + (x + xyz )(x + x y z) (c) Realize XOR gate using minimum number of NAND gates. 3 (a) What are the advantages of Tabulation method over K-map? (b) Simplify the following Boolean function using Tabulation method: Y(A,B,C,D) = (1,3,5,8,9,11,15) 4 (a) Design 4-bit even parity generator. Mention truth table. (b) Design BCD to XS3 code converter using a 4 bit Full- adders MSI circuit. 5 (a) Find the minimal threshold-logic realization for the function: f(a,b,c,d) = Σm(2, 3, 6, 7, 10, 12, 14, 15) (b) Compare programmable logic devices. 6 With a neat sketch explain 4-bit Johnson counter 7 Find the equivalence partition and the corresponding reduce machine in standard form. PS NS 1 Z X = 0 X = 1 A D,0 H,1 B F,1 C,1 C D,0 F,1 D C,0 E,1 E C,1 D,1 F D,1 D,1 G D,1 C,1 H B,1 A,1 8 (a) Draw the ASM chart for binary divider. (b) Draw the state diagram for a full adder circuit and convert it to ASM chart.
Code: 9A04402 ELECTRONIC CIRCUIT ANALYSIS (Common to EIE, E.Con.E & ECE) 1 (a) Explain the classification of amplifiers based on frequency range, type of coupling, power delivered and signal handled. (b) Derive the expression for A i, R i, A v and R o of CB amplifier circuit shown below. 2 (a) Explain different methods used for coupling multistage amplifiers with their frequency response. (b) Five identical stages are coupled, each amplifier having f 2 = 100 KHz. Determine the overall upper cut-off frequency for the five stages. 3 (a) Draw the hybrid - equivalent circuit of BJT and explain the significance of each parameter. Mention typical values of hybrid - parameters. (b) Given the following transistor measurements made at I C = 5 ma, V CE = 10 V and at room temperature h fe = 100, h ie = 600, [A ie ] = 10 at 10 MHz, C e = 3 pf. Find, f T, C e, r b e and r bb. - + 4 (a) Give the low frequency analysis of FET amplifier. (b) The gain of an RC coupled 2 stage FET amplifier falls by 90% of the mid band value at 400 KHz. If g m of each FET is 10 ma/v, and total output capacitance for each stage is 20 pf. Calculate the R L required and the stage mid band gain. 5 (a) Draw the circuit diagram of a voltage shunt feedback using BJT and derive expression for voltage gain with feedback. (b) Draw the circuit for current shunt amplifier and justify the type of feedback. Derive the expression for A v,, R i and R o for the circuit. B + - Contd. in page 2 Page 1 of 2
Code: 9A04402 6 (a) Why the LC oscillators are not suitable for low frequency applications. Explain the principle of working of basic LC oscillators. (b) In a transistorized Hartley oscillator the two inductances are 2 mh and 20 while the frequency is to be changed from 950 KHz to 2050 KHz. Calculate the range over which the capacitor is to be varied. 7 (a) Prove that in class A power amplifier if the distortion is 10% then the power given to the load increased by 1%. (b) A class B push-pull power amplifier has V CC = 50 V, the collector voltage swing from V CC down to 10 V with input signal. If the transistors used as maximum power dissipation rating of 20 W. Calculate (i) The load presented by the output transformer. (ii) Power output. (iii) D.C power input. (iv) Efficiency of collector circuit. (v) Power delivered to the load if the transformer efficiency is 85%. 8 (a) With neat circuit diagram, explain the working of double tuned amplifier. (b) What are advantages of double tuned amplifier? Derive an expression for Ι 2 maximum. http://mothertheresalibrary.blogspot.in/ Page 2 of 2
Code: 9A04404 PULSE & DIGITAL CIRCUITS (Common to ECE, EIE, E.Con.E, ECC & MCT) 1 (a) Explain the response of a high pass circuit, if an exponential input is applied. (b) Write short note on piping process. 2 (a) What is meant by clipping in wave shaping? (b) Classify different types of clipper circuits. Give their circuits and explain their operation with the aid of transfer characteristics. 3 Write short notes on: (a) Diode switching times. (b) Switching characteristics of transistors. (c) FET as a switch. 4 Explain about various switching conditions of Schmitt trigger. 5 (a) What are sweep circuits? (b) Explain how you generate a saw tooth waveform with a neat circuit diagram. 6 (a) Explain the operation of series and shunt FET sampling gates. (b) What are the advantages of FET sampling gates over transistor sampling gates? 7 How synchronization and frequency division are related? What are the methods used for synchronization of monoshot circuit? 8 (a) What is the difference between floating and grounded inputs? (b) Design and explain the concept of discrete type of gates.
Code: 9A04406 ELECTROMAGNETIC THEORY & TRANSMISSION LINES (Electronics & Communication Engineering) 1 (a) What are equipotential surfaces? Explain. (b) Prove that inside a conductor static electric field is zero. 2 (a) Compare the concept of energy storage in electric and magnetic fields. (b) Find the energy stored in the system if five charges of 5 µc each has to be arranged at the vertices of a pentagon of side 5 cm. 3 State and prove all the Ampere s laws applied to magnetic field. 4 (a) Find the capacitance of a isolated sphere of radius R. (b) Considering earth as a conducting sphere of radius 6550 km, calculate the surface charge on it. 5 Derive the expression for, α, β, and ŋ in a good dielectric. 6 (a) Define critical angle. Derive the expression for it. (b) A uniform plane wave transmitting in free space is incident normal to the surface of a perfect conductor. If the total electric field is zero at a distance of 1m away from the surface of the perfect conductor. Determine the lowest possible frequency of the incident wave. 7 (a) A lossless line has a voltage wave v( z, t) v0 sin( t z) (b) ω β =. Find the corresponding current wave. A coaxial cable has an inner conductor of radius a = 0.8 mm and an outer conductor of radius b = 2.6 mm. The conductors have σ c = 5.28 X 10 7 s/m, μ c = μ 0 and ε c = ε 0, they separated by a dielectric material having σ = 10-5 s/m, μ = μ 0, ε c = 3.5 ε 0. At 80 MHz, calculate the line parameters L, C, G, and R. 8 (a) Discuss about quarter wave transformer. (b) Explain the reactance properties of transmission lines.
Code: 9AHS401 MANAGERIAL ECONOMICS & FINANCIAL ANALYSIS (Common to EIE, E.Con.E and ECE) 1 Define managerial economics. Explain its nature and scope. 2 Explain with examples: (a) Price elasticity of demand. (b) Cross elasticity of demand. 3 What are economies of scale? What are its types? Illustrate. 4 (a) What are the causes for the emergence of monopoly? (b) How is the equilibrium position attained by a monopolist under varying cost conditions? 5 (a) Differentiate a private and public company. (b) What is a joint sector management? 6 What do you understand by time value of money? How it is useful in capital budgeting? 7 Explain the following in briefly: (a) Double entry system. (b) Book keeping. (c) Capital. (d) Income. 8 Define ratio. Explain in different classifications of ratio analysis.