The expected answers were:
Advantages of RC coupling
- d.c. isolation between stages;
- simple circuitry;
- has less frequency distortion.
Disadvantages of RC coupling
(i) low overall amplifier gain in multistage design;
(ii) tendency to become noisy with age;
(iii) poor resistance (impedance) matching.
- (i) Negative feedback is introduced in amplifiers to maintain the stability of its operating parameters.
(ii) Advantages of negative feedback
- Reduction of noise
- Reduction of distortion
- Stability of operating parameters
- Input and output impedance can be modified as desired
- Increase bandwidth.
Disadvantage of negative feedback
The question was on amplifiers. Few candidates attempted the question. The performance was average.
The question had two parts; the first part is the purely recall question of stating the advantages of RC-coupling in transistor amplifiers, and the second, another purely recall question, requiring the merits of feedback in amplifier.