SRM University 2007 B.Tech Electronics and Communications Engineering EC202- ELECTRONIC CIRCUITS – II - Question Paper

9. Sketch the circuit of a single stage CA Amplifier that uses voltage sampling –Shunt Mixing . discuss the operation of circuit . Derive expression for Af , Rif, Rof

10. For provided amplifier with CE configuration, determine
i) the kinds of negative feedback
ii) draw the equivalent circuit.
iii) ?. A, Af, Avf, Rif & Rot. presume hre = hoe = 0


11. For provided amplifier, determine
i) the kinds of negative feedback
ii) draw the equivalent circuit.
iii) ?. A, Af, Avf, Rif & Rot. presume hre = hoe = 0





12. For provided amplifier, determine
i) the kinds of negative feedback
ii) draw the equivalent circuit.
iii) ?. A, Af, Avf, Rif & Rot. presume hre = hoe = 0


UNIT – II - OSCILLATORS
Part – A
1. Define an Oscillator. provide a few examples
2. Distinguish ranging from an amplifier and an oscillator.
3. How do you classify oscillator based on different aspects?
4. Define sinusoidal oscillator. provide examples.
5. Define non-sinusoidal oscillator. provide examples.
6. What are damped and undamped oscillations? Show waveforms.
7. What is a tank circuit or oscillatory? discuss its operation.
8. What are the factors responsible for damped oscillations in a LC tank circuit?
9. Explain the ways to overcome the losses in a tank circuit.
10. Explain the principle of operation of Transistor oscillator.
11. State Barkhausen criteria for sine wave oscillation and discuss they must be fulfilled to sustain oscillations.
12. Draw the block diagram of a general feedback oscillator and discuss how oscillations are produced.
13. Calculate the oscillator frequency for the Hartley oscillator for the subsequent circuit values : LRFC = 0.5mH, L1 = 750µH, L2 = 750µH, M = 150µH and C = 150PF.
14. Calculate the oscillator frequency for the Colpitts oscillator for the subsequent circuit values : LRFC = 0.5mH, L = 100µH, C1 = 150PF and C2 = 0.01µF.
15. What are the distinguishing features of Hartley and Colpitts oscillator?
16. What are the advantages of Clapp oscillator over Colpitts oscillator?
17. What are the disadvantages in LC oscillators? How is this overcome in RC oscillators?
18. What are the kinds of RC oscillators?
19. Explain the phase shift principle in Transistor RC Phase shift oscillator.
20. Sketch a diode amplitude stabilization circuit for a phase shift oscillator and discuss its operation.
21. Calculate the operating frequency of a BJT Phase-Shift oscillator for R=6KO, C=1500PF, RC=18KO.

Earning:   Approval pending.