Question
Download Solution PDFApplications of negative feedback to a certain amplifier reduced its gain from 200 to 100. If the gain with the same feedback is to be raised to 150, in the case of another such appliance, the gain of the amplifier without feedback must have been
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
A negative feedback network is shown below.
\(\frac{C}{R} = \frac{A}{{1 + {A_\beta }}} = {A_{eL}}\)
Where A is the gain of the amplifier without feedback and feedback gain = β
Calculation:
Case 1:
Gain without feedback, A = 200
Gain with feedback ACL = 100
\(100 = \frac{{200}}{{1 + 200\;\beta }}\)
\(\beta = \frac{1}{{200}}\)
Case 2:
Gain with feedback, ACL = 150
Feedback, \(\beta = \frac{1}{{200}}\)
\(150 = \frac{A}{{1 + A \times \frac{1}{{200}}}} \)
\( A = 600\)
Last updated on Jul 2, 2025
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