Q. Two Stage Rc Coupled Amplifier?

It is the most popular type of a multistage amplifier because it is cheap and provides excellent audio fidelity over a wide range of frequencies.It is usually employed for voltage amplification.

Coupling capacitor is used to connect the output of first stage to the base i.e, input of second stage and so on.The coupling from one stage to next stage is achieved by a coupling capacitor followed by a connection to a shunt resistor.Such amplifiers are called RC coupled amplifiers.

When an ac signal is applied to the base of the first transistor it appears in the amplified form across its collector load Rc .The amplified signal developed across Rc is given to the base of the next tsage through Cc.The second stage does further amplification.Thus cascaded stages amplifies the signal and the overall gain is increased. The total gain is less than the product of the gain of the individual stages i.e,

Total gain  < β1 × β2

This is because the second stage is made to fall on the first stage .The effective load resistance of the first stage is reduced due to the shunting effect of the input resistance of the second stage.