For a system to work, as oscillator the total phase shift of the loop gain must

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Question
For a system to work, as oscillator the total phase shift of the loop gain must be equal to
Options
A. 90�
B. 45�
C. 270�
D. 360�

Correct Answer

360�

Explanation

Gain of system with + ve feedback =

For a system to work, as oscillator the total phase shift of the loop gain must be equal to 90� 45�

for oscillation

but V₀ ? 0

so, that 1 - AB = 0 ⟹ AB = 1 ?0� or 360�.

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