Draw diagram of class A push-pull amplifier and explain its operation.

Draw diagram of class A push-pull amplifier and explain its operation. 
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Answer :

Class A Push-pull Amplifier: The circuit diagram of class A push-pull amplifier is as shown in the fig.(a). Operation: The resistors R1 and R2 along with Vcc provide the dc biasing so as to keep the operating point (Q-point) at the centre of the dc load line, in order to achieve the class A operation. The driver transformer provides the phase splitting function and produces two voltages Va1 and Va2 which are equal in magnitude but 180 degree out of phase. The Vcc is applied to the collectors of transistors Q1 and Q2 through the centretapped output transformer. 

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