Exams › JEE Main › General

The positive feedback is required by an amplifier to act an oscillator. The feedback here means:

1. External input is necessary to sustain ac signal in output
2. A portion of the output power is returned back to the input
3. Feedback can be achieved by LR network
4. The base-collector junction must be forward biased

Correct answer: A portion of the output power is returned back to the input

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