Question

Given the Wien Bridge shown below C2 R4 U1 0 R1 D1 R3 D2 R2 Al What is the frequency at which it oscillates if R R 47 k, and C C 4.7 nE? B] what is the loop gain T(jf) at startup if R1 = 23 kQ. R2 = 10 kQ, R3 = 100 kO? C] What is the loop gain if the diodes are assuming to be heavily conducting? D] What is the purpose in using the two diodes?

Answer 1

U I R5 PI a) R4 :R5= 47 k, cl=C2 z4.1.n F Given, 2TT RC 千+6 "2 X 10 X 10 fo = 720 Hz R2 10 K R3 100 Kn R2

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