Question

What is the function of a capacitor in the linear analysis of a transistor?

(a) To find the operating point

(b) To block d-c signals

(c) To block a-c signals

(d) Makes no difference

I had been asked this question in class test.

My question is taken from Transistor Amplifier Response, Taking Source Resistance into Account in section High Frequency Transistor of Electronic Devices & Circuits

Answer 1

Right option is (b) To block d-c signals

The best explanation: Capacitors are used in the linear analysis of a transistor circuit taking source resistance into account to block out and isolate the d-c signals while letting the a-c signals pass through. This is useful to calculate the load line in the analysis of the transistor.