IN the standard transformer coupling, single ended situation, the major disadvantage of the method is the average DC current that flows in the circuit must be supported by the transformer, making the transformer relatively large so that it does not saturate due to the DC only. This is probably the most common output coupling method, as it is relatively simple. At quiescent conditions, the power supply voltage appears on the plate (minus a little loss due to the IR loss in the transformer. During signal conditions, the output swings above and below the supply voltage.
akhilesh

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