role of tuned LC circuit in tuned amplifier.

1 Answer

Answer :

In order to pick up and amplify the desired radio frequency signal, the resistive load in the audio amplifier is replaced by a tuned circuit (also called a parallel resonant circuit)as shown in the figure. The tuned circuit is capable of selecting as particular frequency and rejecting the others.

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Thus the use of tuned circuit in the transistor amplifier circuit, makes possible the selection and amplification of a particular desired radio frequency. Such an amplifier is called tuned voltage amplifier. Thus an amplifier, which amplifies a specific frequency (or a narrow band frequencies), is called a tuned voltage amplifier or simply tuned amplifier. It serves following two purposes: (i) Selection of desired radio frequency signal. (ii)Amplification of the selected signal to a suitable voltage level.

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