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In an oscillator, for sustained oscillat...

In an oscillator, for sustained oscillations, Barkhausen criterion is `Abeta` equal to (A = voltage gain without feedback and `beta` = feedback factor)

A

increases the input voltage

B

is always in phase with the input voltage

C

is always in antiphase or `180^@` out of phase with the input voltage

D

transfers a part of the output energy of the amplifier to the resonating L-C circuit

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The correct Answer is:
C
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