Abstract
THE use of negative feedback to give improved performance in a number of important respects is now a well-established feature of amplifier design technique, and the simple mathematical treatment of an amplifier with feedback has been given by a number of writers. The earliest of these accounts was in a paper by Black1, who showed that if an amplifier has a voltage gain of µ times, and an attenuating network is connected between the output terminals and the input terminals in such a way that a voltage equal to a fraction β of the output Voltage is connected in series with, and in opposite phase to, the input voltage, the amplifier gain will be reduced in the ratio l/(1 - µβ) ; but at the same time the distortion voltages for a given fundamental output will be reduced in the same ratio.
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References
Black, H. S., "Stabilised Feedback Amplifiers", Bell System Tech. J. (Jan., 1934).
Peterson, Kreer and Ware, "Regeneration Theory and Experiment", Bell System Tech. J. (Oct., 1934).
Bode, H. W., "Feedback Amplifier Design", Bell System Tech. J. (July, 1940).
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WASS, C. FEEDBACK AMPLIFIERS. Nature 150, 381–382 (1942). https://doi.org/10.1038/150381a0
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DOI: https://doi.org/10.1038/150381a0