FET_FOR_AGC

Published:2009/7/16 2:42:00 Author:Jessie | From:SeekIC

Uses 2N2498 fet as variable-emitter resistor in common-emitter transistor amplifier. Low-current 2N3328 is used to supply constant emitter bias current and have very light dynamic loading on emitter for maximum agc range. Since variable resistor is capacitor-coupled to emitter of transistor, there is no change in bias current when strong agc voltage is suddenly applied. Absence of transient thump makes circuit desirable for broadcast speech compressors.-L. J. Sevin, Jr., Field-Effect Transistors, McGraw-Hill, N.Y., 1965, p 78.



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