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Code No: R7102303
I B.Tech (R07) Regular & Supplementary Examinations, June 2009 BASIC ELECTRICAL AND ELECTRONICS ENGINEERING (Bio-Technology) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. An impedance ZI = (2 + j3) Ω is in parallel with another impedance Z2 = (3 -j4) Ω. The combination is given a supply of 220 V. Calculate the current in each branch, impedance, reactive power, total current and apparent power, power factor of the circuit. [16] 2. (a) Discuss the various three phase transformer groups and their significance. (b) Compare the commonly used three phase connections. 3. What are the necessary torques required in an indicating instrument? Explain.
[12] [4] [16]
4. Draw and explain V-I characteristics ofa zener junction and show how a zener diode acts as voltage regulator. [16] 5. Distinguish between the different types of transistor configurations with necessary circuit diagrams, using transistor. [16] 6. Describe the operation of Class B push pull amplifier and also explain how the crossover distortion is minimized? [16] 7. State and explain the Barkhuesen criterion and also derive an expression for the condition for oscillation. [16] 8. (a) Convert the following binary number to octal and decimal: i. 11011100.101010 ii. 10110011. (b) Explain the following codes and mention their application : i. ASCII code. ii. Hamming code.
[16] ?????
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Code No: R7102303
I B.Tech (R07) Regular & Supplementary Examinations, June 2009 BASIC ELECTRICAL AND ELECTRONICS ENGINEERING (Bio-Technology) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. Define average value and obtain in the same for a half wave rectified voltage wave with and without filters. [16] 2. (a) Discuss the various three phase transformer groups and their significance. (b) Compare the commonly used three phase connections.
[12] [4]
3. Justify the necessity of controlling torque in indicating instruments. Discuss the various methods of producing the same. Compare them. [16] 4. Sketch the V-I chacteristics of a Triac with function of triac.
[16]
5. Sketch a typical transfer characteristics for an N-channel JFET and show how the trans conductance can be derived from the transfer characteristics. [16] 6. Distinguish between single tuned, double tuned and stagger tuned amplifier. Discuss the effect of ‘Q’ on band width of a tuned amplifier. [16] 7. Describe the analysis of RC phase shift oscillator.
[16]
8. Using Karnangh map simplify the following switching function : f (A, B, C, D) = S (1, 3, 5, 8, 9, 11, 15) + Σ (2, 13) and implement the function using NAND gates. [16] ?????
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Code No: R7102303
I B.Tech (R07) Regular & Supplementary Examinations, June 2009 BASIC ELECTRICAL AND ELECTRONICS ENGINEERING (Bio-Technology) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. Define average value and obtain in the same for a half wave rectified voltage wave with and without filters. [16] 2. (a) Discuss the various three phase transformer groups and their significance. (b) Compare the commonly used three phase connections.
[12] [4]
3. What do you understand by attraction type and repulsion type instruments? What are the important difference between moving coil and moving iron instruments? [16] 4. Sketch the V-I chacteristics of a Triac with function of triac.
[16]
5. Distinguish between the different types of transistor configurations with necessary circuit diagrams, using transistor. [16] 6. Derive the expressions for input resistance, output resistance, voltage and current gain of a CE amplifier with voltage divider bias using hybrid model only. [16] 7. What is blocking oscillator. Explain the operation of base timing blocking oscillator. Give its uses and advantages. [16] 8. Obtain the expression for difference and borrow outputs of a full subtractor and implement the same NOR gates only. [16] ?????
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Code No: R7102303
I B.Tech (R07) Regular & Supplementary Examinations, June 2009 BASIC ELECTRICAL AND ELECTRONICS ENGINEERING (Bio-Technology) Time: 3 hours Max Marks: 80 Answer any FIVE Questions All Questions carry equal marks ????? 1. A balanced delta connected load of (8 + j7) Ω / phase is connected to a 3 phase, 230V supply. Find the line current, power factor, power, reactive volt-amperes and total volt- amperes. [16] 2. Describe the constructional features of a dc machine with neat sketch.
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3. What are the necessary torques required in an indicating instrument? Explain.
[16]
4. What is a zener diode? Draw the equivalent circuit of an ideal zener in the breakdown region. Why is zener diode used as a voltage regulator? [16] 5. Explain the following: (a) Emitter region is highly doped. (b) Base region is narrow. (c) Transistor is called ?transfer resistor‘.
[16]
6. Explain the following: (a) Unilaterlisation. (b) Unity gain frequency. (c) Synchronously tuned amplifier.
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7. A Hartley oscillator is designed with L1 = 2mH, L2 = 20µH and a variable capacitance. Determine the range of capacitance values is the frequency of oscillation is varied from 2050 KHz to 3050 KHz. [16] 8. Using Karnangh map simplify the following switching function : f (A, B, C, D) = S (1, 3, 5, 8, 9, 11, 15) + Σ (2, 13) and implement the function using NAND gates. [16] ?????