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Question 8 [9 marks] A class A BJT amplifier is biased with a Q-point given by Ica = 1.1 mA; VCEQ = 7 V. You also know the ac quantities Ic(sat) = 5 mA and Vce(cutoff) = 9 V. (Useful formula: Vrms = V peak) 8.1 (a) Draw the ac load line on a set of axes. Indicate the values for the x & y intercepts and draw the Q- point on the load line. [1] 8.1 (b) What is the maximum allowable variation for lc before there is any kind of distortion? [1] 8.1 (c) On a set of axes, draw the output waveform for V. given that it has a peak variation of 1.5 V. [1.5] 8.1 (d) On a separate set of axes draw Vc given that it has a peak variation of 2.5 V. [1.5] Answer the following questions. 8.2 (a) Between class-A and class-B amplifiers, which one would have more harmonic noise? [1.5] 8.2 (b) If the voltage gain of an amplifier goes up by two times, how much would the power gain go up by? [1] 8.2 (c) What is the difference between power gain and the efficiency of a power amplifier? [1.5]