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3 D 10684
(1) Draw the d.c. loadline.
(ii) Determine the operating point.

16. With a negative voltage feedback, an amplifier gives an output of 10 V with an input of 0.5 V.
When feedback is removed, it requires 0.25 V input for the same output. Calculate : (i) Gain
without feedback ; (ii) Gain with feedback ; and (iii) Feedback fraction.

17. Aphase shift oscillator uses 0.01 uF capacitors, Find the value of Resistance R to produce a frequency
of 800 Hz.

18. Describe the principle of a summing amplifier using op-amp.
19. Compute the following using 2’s complement method :
(a) 25-18. (b) 9-12.
(5 x 5 = 25 marks)
Section C (Essay Type)
Answer any one question.
The question carries 11 marks.

20. Describe voltage divider biasing in detail, Explain how stability is achieved in this method.

21. Explain the principle of a full adder with suitable diagrams and truth table.
(1 x 11 = 11 marks)

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